Rapid size-specific changes in the drift of Baetis bicaudatus (Ephemeroptera) caused by alterations in fish odour concentration - A. R. McIntosh; B. W. Taylor; B. L. Peckarsky (Oecologia, 1999)

Nectar-robbing bumble bees reduce the fitness of Ipomopsis aggregata (Polemoniaceae) - Alison K. Brody; Rebecca E. Irwin (Ecology, 1999)

The effect of experimental ecosystem warming on CO2 fluxes in a montane meadow - M. S. Torn; S. R. Saleska; John Harte (Global Change Biology, 1999)
AbstractClimatic change is predicted to alter rates of soil respiration and assimilation of carbon by plants. Net loss of carbon from ecosystems would form a positive feedback enhancing anthropogenic global warming. We tested the effect of increased heat input, one of the most certain impacts of global warming, on net ecosystem carbon exchange in a Rocky Mountain montane meadow. Overhead heaters were used to increase the radiative heat flux into plots spanning a moisture and vegetation gradient. We measured net whole‐ecosystem CO2 fluxes using a closed‐path chamber system, relatively nondisturbing bases, and a simple model to compensate for both slow chamber leaks and the CO2 concentration‐dependence of photosynthetic uptake, in 1993 and 1994. In 1994, we also measured soil respiration separately. The heating treatment altered the timing and magnitude of net carbon fluxes into the dry zone of the plots in 1993 (reducing uptake by ≈100 g carbon m–2), but had an undetectable effect on carbon fluxes into the moist zone. During a strong drought year (1994), heating altered the timing, but did not significantly alter the cumulative magnitude, of net carbon uptake in the dry zone. Soil respiration measurements showed that when differences were detected in dry zone carbon fluxes, they were caused by changes in carbon input from photosynthesis, not by temperature‐driven changes in carbon output from soil respiration. When differences were detected in dry‐zone carbon fluxes, they were caused by changes in carbon input from photosynthesis, not by a temperature‐driven changes in carbon output from soil respiration. Regression analysis suggested that the reduction in carbon inputs from plants was due to a combination of two soil moisture effects: a direct physiological response to decreased soil moisture, and a shift in plant community composition from high‐productivity species to low‐productivity species that are more drought tolerant. These results partially support predictions that warming may cause net carbon losses from some terrestrial ecosystems. They also suggest, however, that changes in soil moisture caused by global warming may be as important in driving ecosystem response as the direct effects of increased soil temperature.

Flower constancy, insect psychology, and plant evolution - L. Chittka; Nickolas M. Waser; James D. Thomson (Naturwissenschaften, 1999)
The way in which floral parameters, such as interplant distances, nectar rewards, flower morphology, and floral color affect constancy is considered, and the implications of pollinator constancy for plant evolution are discussed.

Floristic Inventory of the Northern Gunnison Basin - K. J. Taylor (1999)

Assessment of a revegetation project on Mt. Crested Butte - K. Mahady (1999)

Invertebrates in Freshwater Wetlands of North America: Ecology and Management (1999)

Dispersal of the fairy shrimp Branchinecta coloradensis (Anostraca): Effects of hydroperiod and salamanders - A. J. Bohonak; Howard Whiteman (Limnology and Oceanography, 1999)
The absence of fairy shrimp (Anostraca) from permanent ponds and lakes is hypothesized to be the result of vertebrate predation. However, hatching cues for anostracan diapausing eggs include factors associated with the filling of temporary pond basins, and desiccation often increases the fraction of eggs that hatch. Thus, it is possible that in some species, eggs dispersed to permanent habitats never hatch, and vertebrate predation is not the proximate factor limiting distributions. We experimentally transplanted live egg‐bearing females of the fairy shrimp Branchinecta coloradensis into permanent and temporary ponds in small chambers and allowed the chambers to overwinter in situ. There was no discernible effect of pond drying on hatching success (mean success = 50.9%). We also determined whether metamorphic salamanders (Ambystoma tigrinum nebulosum) could disperse viable fairy shrimp eggs by feeding on B. coloradensis in one pond and defecating in another. Hatching success for a salamander “ingested” treatment was estimated as 0.9%. Results of a third experimental treatment suggested that the eggs being carried by females were not fully mature, so that ingestion resistance might vary throughout the reproductive period of B. coloradensis. By combining these results with data on salamander movement and diet, we estimated salamander‐mediated dispersal rates for fairy shrimp eggs. Metamorphic A. tigrinum nebulosum sp. are likely to be dispersing thousands of B. coloradensis eggs among ponds annually. Because our results demonstrate that dispersal between ponds can occur in large numbers, they support the prevailing hypothesis that vertebrate predators limited to permanent ponds are the proximate mechanism preventing the invasion of fairy shrimp.

Effects of Local Density on Pollination and Reproduction in Delphinium nuttallianum and Aconitum columbianum (Ranunculaceae) - M. Bosch; Nickolas M. Waser (American Journal of Botany, 1999)
Plant populations vary in density both naturally and as a consequence of anthropogenic impacts. Density in turn can influence pollination by animals. For example, plants in dense populations might enjoy more frequent visitation if pollinators forage most efficiently in such populations. We explored effects of plant density on pollination and seed set in the larkspur Delphinium nuttallianum and monkshood Aconitum columbianum. At our site in the Colorado Rocky Mountains, flowers of D. nuttallianum are pollinated primarily by queen bumble bees, solitary bees, and hummingbirds, whereas those of A. columbianum are pollinated primarily by queen and worker bumble bees. We found that the quantity of pollination service to both species (pollinator visitation rate and pollen deposition) was at best weakly related to density. In contrast, seed set declined by approximately one‐third in sparse populations relative to nearby dense populations. This decline may stem from the receipt of low‐quality pollen, for example, inbred pollen. Alternatively, sparsity may indicate poor environmental conditions that lower seed set for reasons unrelated to pollination. Our results demonstrate the value of simultaneously exploring pollinator behavior, pollen receipt, and seed set in attempting to understand how the population context influences plant reproductive success.

Invertebrates in Freshwater Wetlands of North America: Ecology and Management (1999)

Religious Art: Reflectors of Change in the Catholic Church in New Mexico, 1830--1910. - Shirley Sands (1999)
In 1846, the United States of America began a war with the Republic of Mexico. When it was over, one of the results was the acquisition of much of current California, Arizona, Nevada, Utah, southern Colorado and New Mexico. The region was occupied by Catholic Mexicans, a fact not lost on the American Catholic hierarchy. The result is the sending of a new religious administration and the founding of what would become the Archdiocese of Santa Fe. The clergy sent were French with French notions of civilization, culture, and proper Catholic theology. These views and notions were contrary to those held by the Spanish-speaking population of the region and a struggle began. By using the religious art of Jesus and the Virgin Mary, and secondarily the architecture, found in several sacred sites, in a number of different locations, the depth of French clerical influence is measured from the years 1830 through 1910. The iconography of the subjects is examined as well as the forms of the art, where they are placed, and the history of each in the French or Spanish traditions. Through the use of inventories and written records kept by the Spanish and Mexican priests and the post-American conquest records of photographs, and studies by anthropologists, art historians, folklorists, and historians change can be traced. Not surprisingly, Santa Fe, the political, economic and ecclesiastical center of the new archdiocese reflected the maximum amount of change in the religious art and architecture in the Catholic church while the sites located in the rest of the study reflect less and less influence the farther from the center of power they are with the moradas of the Pentitential brotherhoods showing no influence at all.

Courtship behavior in a polymorphic population of the Tiger Salamander, Ambystoma tigrinum nebulosum - R. S. Moorman; J. J. Gutrich; Howard Whiteman (Journal of Herpetology, 1999)

Nectar on Tap? The Nectar Secretion Schedules of Two Species of Penstemon - J. Blackwood (1999)

Delayed egg hatching and semivoltinism in the nearctic stonefly Megarcys signata (Plecoptera:Perlodidae) - C. G. Anderson; B. W. Taylor; B. L. Peckarsky (Aquatic Insects, 1999)
Delayed egg hatching can influence the survival of aquatic insects by reducing exposure to competi- tors, predators, parasites, or unfavorable environmental conditions. We examined egg development in a Colorado population of the stonefly, Megarcys signata (Plecoptera: Perlodidae), whose larvae in- habit high altitude streams in the Rocky Mountains of western North America. Five-thousand ferti- lized eggs were collected from 40 different females and incubated in the East River, Gunnison County, Colorado, until late fall, at which time unhatched eggs were transported to incubation chambers in Ithaca, New York. We used three different combinations of photoperiod and temperature (10L:14D, 4°C; 10L:14D, 8°C; 8L:16D, 8°C) in an attempt to induce hatching. Eggs in the treatments with temperatures elevated above normal winter temperatures in the East River (8°C) began developing after 6 months, whereas eggs in the treatment most closely simulating natural stream conditions (4°C) did not hatch after 10 months of incubation. Our data indicate that this population of Megarcys signata has an extended egg stage that persists for almost a year, and that it is semivoltine at these elevations of 2885 and 2895 meters.

Evolution of sociality in marmots - Kenneth B. Armitage (Journal of Mammalogy, 1999)
The 14 species of marmots (Marmotd) can be placed in one of four social systems: solitary; female kin matriline; adult male with two females and immature offspring; and a family group consisting of a territorial pair, subordinate adults, and immature offspring. Body size and hibernation are two critical features of marmot biology from which sociality evolves. The high correlation (r = 0.91) between immergence mass and mass loss suggests that species are heavier because they require more mass to survive the hibernation period. Marmots increase mass either by having a larger frame or by increasing the amount of mass per frame. Emergence and immergence mass are linearly related to body length; but change in mass is curvilinearly related to body length: large species use relatively more mass. An analysis of mass:length ratios reveals that species with a relatively high immergence mass use considerable mass during the hibernation period whereas species with a relatively high emergence mass use considerable mass after emergence. The consequence of large body size and a short growing season is that young in all but one species require two or more growing seasons to reach reproductive maturity. All species reach a maturity index for dispersal by age one; however, only two species disperse by that age and several species delay dispersal beyond the age of first reproduction. All species are reproductively mature by age two, but many species delay reproduction for one or more years. Delayed dispersal produces social groups of high relatedness. A cost of sociality is reproductive suppression; reproductive loss is partially compensated by increased survivorship and alloparental care. Subordinate adults also may reproduce or succeed to territorial status. Alloparental care occurs during hibernation when subordinate adults assist in social thermoregulation of closely related young. Thus, marmots have the characteristics of cooperative breeding. The following sequence of events is hypothesized to have occurred in the evolution of marmot sociality. Large size and a short growing season required the retention of offspring in their natal group for one or more additional years to reach maturity. Habitat saturation led to delayed dispersal, which in turn, increased survivorship. When subordinate adults remained in the social unit, they could participate in social thermoregulation and alloparental care.

The Commonality of Herbivorous Trophic Links with Regard to Spatial Scale - L. B. Buckley (1999)

Colonial Costs and their Effects on the Behavior of Nestling Feeding and Nest Occupation in the Cliff Swallow - C. Hess (1999)

Vertebrate and Invertebrate Pollinators of Distegia involucrata/Lonicera involucrata (Capriofoliaceae) of RMBL Gothic, CO - R. Hackney (1999)

An Irvingtonian species of Brachylagus (Mammalia: Lagomorpha) from Porcupine Cave, Park County, Colorado - Colleen N Ramos (The Great Basin naturalist., 1999)
Abstkact. -Bracliijla^us i.s ciiircntK a inonotNiiic ^I'liu.s ol unct'itaiii oiitiiiis and known only from Iloloccne and late Raiicholabrean. A new species ot leporid is clescrii)ed from the early and middle Pleistocene (Irvinj^tonian) deposits of Poreiipine Cave, Park CountN; Colorado. Stratified deposits of the Pit and the Velvet Room, 2 localities within Porcu-I)ine Cave, have been dated hiochronologieally and paleomagnetically from the middle Irvinj^tonian and early to middle Iningtonian, respectively. Brachijla<>.u.s colorudoensis, sp. now, is characterized by its conserved p3 enamel jiatterns which are intermediate between B. idahoeusis and Hypohifius, and its size which is slightly larger than that of B. idahoeusis. This snggests a possible ancestral relationshiji between Ihjpolanus and Br(ichi/la<^iis.

The effects of ungulate herbivory on phenology, pollination, and reproductive success in Ipomopsis aggregata - K. E. Sharaf (1999)

A comparison effort between hermaphrodites and females of Geramium richarsonii; Implications for maintenance of gynodioecy - M. Tovar (1999)

Gatherings of Angels: Migrating Birds and Their Ecology - W. A. Calder (1999)

The use of mark/recapture to measure worker number in the rock nesting species Formica neorufibaris - Ian Billick (Insectes Sociaux, 1999)

The ecological effects of nectar robbers, with an emphasis on the reproductive biology of Corydalis caseana - J. E. L. Maloof (1999)

Factors affecting scent marking behavior in the North American Beaver (Castor canadensis) - J. Pierce (1999)

Pre-dispersal seed predation by Hylemya sp. in a plant hybrid zone of Ipomopsis aggregata and I. tenuituba - M. Crawford (1999)

Estimating species-area relationships from plot to landscape scale using species spatial-turnover data - S. McCarthy; A. P. Kinzig; M. L. Fischer; K. J. Taylor; John Harte (Oikos, 1999)
John Harte, Sarah McCarthy, Kevin Taylor, Ann Kinzig, Marc L. Fischer, Estimating Species-Area Relationships from Plot to Landscape Scale Using Species Spatial-Turnover Data, Oikos, Vol. 86, No. 1 (Jul., 1999), pp. 45-54

A Census of Molothrus ater in the East RIver and Ohio Creek Valleys - P. Pressman (1999)

From populations to ecosystems: studies on the distribution, importance, and loss of biodiversity - John M. Hughes (1999)

Fluctuating Asymmetry:Environmental causes in adult and larval tiger salamanders, Ambystoma tigrinum nebulosum - J. Boynton (1999)

Invertebrates in Freshwater Wetlands of North America: Ecology and Management - L. J. Gallagher; A. J. Bohonak; W. S. Brown; Howard Whiteman; S. A. Wissinger; S. A. Wissinger; S. A. Wissinger (1999)

Cooperative breeding in marmots - Kenneth B. Armitage; Daniel T. Blumstein (Oikos, 1999)
Whenever individuals live in stable social groups and not all individuals breed, group members may breed cooperatively. While well-documented in a variety of birds and mammals, there is some controversy over whether, and to what degree, sciurid rodents breed cooperatively. We identify cooperative breeding when: individuals delay dispersal beyond reproductive maturity, reproduction in mature individuals is suppressed, and when non-breeders provide alloparental care. In this paper we note that the 14 species of marmots (Marmota spp.), large ground-dwelling sciurid rodents found throughout the Northern Hemisphere, provide an excellent taxon in which to study the evolution of cooperative breeding. Marmot species fit none, some, or all of the attributes of cooperative breeding. Most interestingly, delayed dispersal and alloparental care may be de-coupled interspecifically, and possibly intraspecifically, making marmots an excellent taxon for additional study. Environmental harshness increases maturation time and is associated with dispersal delayed beyond reproductive maturity. The opportunity to gain direct fitness may be associated with gaining indirect fitness by alloparental behavior. In addition to its theoretical attraction, cooperative breeding has profound implications for conservation and management of species that breed cooperatively. To maximize marmot production, managers and breeders need to pay particular attention to social group structure to prevent the expression of reproductive suppression. If cooperative breeding results from an environmental constraint, habitat modifications may increase the percent of females that breed.

Paleoglacier reconstruction and late Pleistocene equilibrium-line altitudes, southern Sawatch Range, Colorado - B. S. Goldstein (1998)

Food supplementation and its influence on sex ratios and body weights of Spermophilus lateralis in Gothic, Colorado - E. Wall (1998)

Alpine vascular flora of Hasley Basin, Elk Mountains, Colorado, USA - R. V. Seagrist; K. J. Taylor (Madrono, 1998)

Effects of size at metamorphosis on stonefly fecundity, longevity, and reproductive success - C. G. Anderson; B. W. Taylor; B. L. Peckarsky (Oecologia, 1998)
The data suggest that selection pressures determining body size at metamorphosis may operate independently on males and females, resulting in evolution of sexual size dimorphism, protandry, and mating early in the adult stage.

The variation in tree growth performance relative to a climate change along an elevation gradient - V. X. Vela (1998)

Epibiosis of Colacium on Daphnia - R. Bartlett; R. L. Willey (1998)

Effects of supplemental food on growth and mobility of the golden-mantled ground squirrel, Spermophilus lateralis - E. Yates-Doerr (1998)

Alpine vascular flora of Buffalo Peaks, Mosquito Range, Colorado, USA - R. V. Seagrist; K. J. Taylor (Madrono, 1998)

A brief overview of the Quaternary History of the Taylor River Basin (1998)

"Floral" scent production by Puccinia rust fungi that mimic flowers - B. A. Roy; Robert A. Raguso (Molecular Ecology, 1998)

Does insect abundance affect bat activity in three subalpine habitats? - N. Doerr (1998)

A study of the colonization of fallen aspen by decomposers over time after avalanche activity - T. Grahl (1998)

Why do yellow-bellied marmots call? - Kenneth B. Armitage; Daniel T. Blumstein (Animal Behavior, 1998)
This work addressed if and how yellow-bellied marmot, Marmota flaviventris, alarm-calling behaviour was influenced by the presence or absence of both descendent and nondescendent kin, by using total r as a measure of the opportunity for kin selection.

Dispersal and gene flow in freshwater invertebrates - A. J. Bohonak (1998)

Empirical considerations on the stable age distribution - O. A. Schwartz; Kenneth B. Armitage (Oecologia Montana, 1998)

The daily behavior of Eutamias minimus in a town setting - S. Ochs (1998)

Types of disturbances that favor success of Matricaria perforata: a roadside vs. a cemetery - K. Guimond (1998)

Do beaver, Castor canadensis, follow optimal foraging in Gothic, Colorado - K. Lautenschlager (1998)

Effects of food supplementation on a population of golden-mantled ground squirrels, Spermophilus lateralis - Wendell Paddock (1998)

Phenotypic plasticity of a larval caddisfly along a predator-permanence gradient in subalpine wetlands - S. A. Lopez (1998)

Bedazzled by flowers - L. Chittka; Nickolas M. Waser (Nature, 1998)
It is concluded that bees prefer to visit magenta-coloured flowers with a sparkling surface, which has implications for the idea of ‘pollination syndromes’, whereby certain plants are thought to be adapted to attract particular pollinators.

A manual of the common North American species of the aquatic leafmining genus Hydrellia (Diptera: Ephydridae) - D. L. Deonier (1998)

Time allocation to behavior in marmots: a comparison of adults and juveniles (1998)

Differentiating the effects of origin and frequency in reciprocal transplant experiments used to test negative frequency-dependent selection hypotheses - B. A. Roy (Oecologia, 1998)
Contrary to expectations, clones at their site of origin had less disease, less herbivory, and higher fitness than foreign clones, suggesting that the number of sites and clones needed to thoroughly test the hypothesis of negative frequency-dependent selection in this system is very large.

Changes in Aspen Communities Over 30 Year in Gunnison County, Colorado - S. NcNulty; J. Crawford; J. Sowell (American Midland Naturalist, 1998)

Head and body size relationship in polymorphic tiger salamander larvae from Colorado - J. P. Sheen; Howard Whiteman (Copeia, 1998)

Aggregation as a cost reducing strategy for lycaenid larvae - A. H. Axen; N. E. Pierce (Behavavioral Ecology, 1998)

Effects of food supplementation on a population of golden-mantled ground squirrel, Spermophilus lateralis - Angela Wright (1998)

Trapline foraging by bumble bees: III. Temporal patterning of visits - N. M. Williams; James D. Thomson (Behavioral Ecology, 1998)

Comparison of Aquilegia coerulea and Urtica gracilis growing on and off talus - John Ward Smith (1998)

A comparison of behavior in two marmot populations - F. MacCarty (1998)

Topographic effects on upper elevation distribution and abundance of Artemisia tridentata Nutt - I. Fischer (1998)

An assessment of bat activity and insect abundance between three sub-alpine habitats in central Colorado - K. O'Brien (1998)

Herbivory patterns in response to climate change in a sub-alpine meadow - J. Call (1998)

Pollen competition and the frequency of hybridization between two species of Ipomopsis (Polemoniaceae) - R. Alarcon (1998)

Phoretic mite distributions among the burying beetle, Nicrophorus investigator - J. Dinnel (1998)

Does insect abundance affect bat activity? - ERIC R. Allen (1998)

Sex-specific fitness payoffs in a facultatively paedomorphic population of the tiger salamander Ambystoma tigrinum nebulosum - Angela Wright (1998)

A survey of two vascular plant populations: one within and one outside of a turf of the moss Anlacomnium sp. - S. R. West (1998)

Estimation of selfing rate and inbreeding depression in gynodioecious Geranium richardsonii F. & T - K. O'Malley (1998)

The effect of trout on the diversity, richness and abundance of the mayfly species - K. Lautenschlager (1998)

Time allocation to behavior in marmots: a comparison of adults and juveniles - A. Kocis; M. S. Swift (1998)

Genetic population structure of the fairy shrimp Brachinecta coloradensis (Anostraca) in the Rocky Mountains of Colorado - A. J. Bohonak (Canadian Journal of Zoology, 1998)
Dispersal rates for freshwater invertebrates are often inferred from population genetic data. Although genetic approaches can indicate the amount of isolation in natural populations, departures from an equilibrium between drift and gene flow often lead to biased gene flow estimates. I investigated the genetic population structure of the pond-dwelling fairy shrimp Branchinecta coloradensis in the Rocky Mountains of Colorado, U.S.A., using allozymes. Glaciation in this area and the availability of direct dispersal estimates from previous work permit inferences regarding the relative impacts of history and contemporary gene flow on population structure. Hierarchical F statistics were used to quantify differentiation within and between valleys (thetaSV and thetaVT, respectively). Between valleys separated by 5-10 km, a high degree of differentiation (thetaVT = 0.77) corresponds to biologically reasonable gene flow estimates of 0.07 individuals per generation, although it is possible that this value represents founder effects and nonequilibrium conditions. On a local scale (<=110 m), populations are genetically similar (thetaSV = 0.13) and gene flow is estimated to be 1.7 individuals exchanged between ponds each generation. This is very close to an ecological estimate of dispersal for B. coloradensis via salamanders. Gene flow estimates from previous studies on other Anostraca are also similar on comparable geographic scales. Thus, population structure in B. coloradensis appears to be at or near equilibrium on a local scale, and possibly on a regional scale as well.

Reproductive strategies of yellow-bellied marmots: energy conservation and differences between the sexes - Kenneth B. Armitage (Journal of Mammalogy, 1998)
Yellow-bellied marmots (Marmota jlaviventris) conserve maintenance energy by reducing resting metabolic rate, decreasing conductance, avoiding thermal stress, by an annual cycle of metabolism, and by reducing metabolic rate and conductance following the mid summer molt. Male reproductive strategies include successful dispersal and locating females, establishing a territory and shifting energy use to summer defense, becoming polygynous and including as many females as possible within the territory, spending more time aboveground, and hibernating in the area where females are present. The major female reproductive strategy is the fonnation of matrilines, which facilitates the acquisition of resources, increases reproductive output, and provides a reproductive competitive advantage. Females also share space and are amicable with close kin, are agonistic toward all other females, may suppress the reproduction of other females, including their daughters, and produce daughter-biased sex ratios when recruitment of daughters is highly probable. Conflict occurs between males and females because female competition limits the number of females that reproduce whereas male reproductive success increases directly with the number of females weaning litters.

Hummingbird foraging at experimental patches of flowers: evidence for weak risk-aversion - J. A. McRobert; Nickolas M. Waser (Journal of Avian Biology, 1998)
Hummingbirds foraging for nectar in mountains of the western USA encounter spatially-variable rewards under energetically-demanding environmental conditions. Previous workers have found that hummingbirds respond quickly to the average quantity and quality of reward; in addition, one might expect a response to reward variance. To explore this possibility we observed free-flying hummingbirds visiting two arrays of the native plant Ipomopsis aggregata. All flowers in one array received a 1 lI aliquot of artificial nectar whereas every fifth flower in the other array received 5 stl. This yielded a mean nectar standing crop similar to that found in nature, and variances in standing crop that were only slightly more extreme than those in nature. Over 12 days we recorded 362 foraging bouts by male and female Broad-tailed Selasphorus platycercus and Rufous S. rufus Hummingbirds. The high-variance (HV) array received 8.9% fewer foraging bouts than the low-variance (LV) array, and this difference was significant statistically at the ao = 5.4% level. Bout frequency varied among periods of the day, but not differentially by nectar treatment. Foraging bouts tended to be longer in the LV array, though not significantly so, and hummingbirds visiting both arrays in sequence were significantly more likely to visit the LV array first. These results suggest weak risk-aversion under natural conditions. Lack of a stronger response may derive from the fact that hummingbirds sample thousands of flowers a day, so that the total profit realized over a day is not strongly influenced by flower-to-flower variation.

Natural History of Diuraphis (Homoptera: Aphididae) Species Occurring in Western Colorado - Frank B. Peairs; Robert W. Hammon (SPIE eBooks, 1998)
Three species of Diuraphis in addition to the Russian wheat aphid, Diuraphis noxia (Mordvilko), occur in western Colorado. Diuraphis (Holcaphis) tritici (Gillette), the western wheat aphid, and Diuraphis nodulus (Richards) were collected near Meeker (Rio Blanco County) in 1990. Both species were found feeding in seed production fields of mountain brome, Bromus marginatus, and have required chemical control at times to avert economic damage. Diuraphis (H.) frequens Walker was found in 2 localities in 1990. It was found in all but 1 growing season since that time in the West Elk Wilderness (Gunnison County), feeding on blue wild rye, Elymus glaucus. Males and oviparae of all 3 species were collected in 1991. Eggs of D. (H.) tritici and D. nodulus were collected in the spring and again in the fall of 1992. Two species of parasitic Hymenoptera, and 2 species of hyperparasites were collected from D. (H.) tritici and D. nodulus during the study. Several predatory beetles, flies, true bugs, and green lacewings were collected from all of the Diuraphis species.

Annotated checklist of the recent mammals of Colorado - Jennifer. Saldaña-DeLeon; Cynthia S. Jones (Occasional papers - Museum, Texas Tech University, 1998)
Several significant works on the Recent mammals of Colorado have been published, including Armstrong et al. (1994) sum¬ marized information on distribution and ecology of bats.

Pollen transfer by natural hybrids and parental species in an Ipomopsis hybrid zone - P. G. Wolf; Nickolas M. Waser; Diane R. Campbell (Evolution, 1998)

Nectar Robbing in Ipomopsis aggregata: Effects on Pollinator Behavior and Plant Fitness - Alison K. Brody; Rebecca E. Irwin (Oecologia, 1998)

A trade-off between the frequency and duration of bumblebee visits to flowers - Kenneth L. Jones; J. S. Reithel; Rebecca E. Irwin (Oecologia, 1998)
The potential for a trade-offs between these two components of pollinator service exists when visit duration depends on reward quantity; whether the trade-off is realized will depend on variation in nectar production and on whether pollinators forage systematically.

The effect of feeding supplement on time budgets in yellow-bellied marmots (Marmota flaviventris) - John Ward Smith (1998)

The effects of spatial isolation on male and female functions in Ipomopsis aggregata - N. Thorne (1998)

A comparison of bird diversity in aspen and coniferous tree stands at equal elevation - M. Ruehmann; A. F. Camfield (1998)

Variation in lifetime male fitness in Ipomopsis aggregata: tests of sex allocation theory - Diane R. Campbell (American Naturalist, 1998)

Effects of experimental warming on plant reproductive phenology in a subalpine meadow - Mary V. Price; Nickolas M. Waser (Ecology, 1998)
Increasing “greenhouse” gases are predicted to warm the earth by several degrees Celsius during the coming century. At high elevations one likely result is a longer snow-free season, which will affect plant growth and reproduction. We studied flowering and fruiting of 10 angiosperm species in a subalpine meadow over 4 yr, focusing on plant responses to warming by overhead heaters. The 10 species reproduced in a predictable sequence during 3–4 mo between spring snowmelt and fall frosts. Experimental warming advanced the date of snowmelt by almost 1 wk on average, relative to controls, and similarly advanced the mean timing of plant reproduction. This phenological shift was entirely explained by earlier snowmelt in the case of six plant species that flowered early in the season, whereas four later-flowering species apparently responded to other cues. Experimental warming had no detectable effect on the duration of flowering and fruiting, even though natural conditions of early snowmelt were associated with longer duration and greater overlap of reproduction of sequentially flowering species. Fruit set was greater in warmed plots for most species, but this effect was not significant for any species individually. We conclude that global warming will cause immediate phenological shifts in plant communities at high elevations, mediated largely through changes in timing of snowmelt. Shifts on longer time scales are also likely as plant fitnesses, population dynamics, and community structure respond to altered phenology of species relative to one another and to animal mutualists and enemies. However, the small spatial scale of experiments such as ours and the inability to perfectly mimic all elements of climate change limit our ability to predict these longer term changes. A promising future direction is to combine experiments with study of natural phenological variation on landscape and larger scales.

Cryptic species in the Puccinia monoica complex - D. Vogler; T. Bruns; T. Szaro; B. A. Roy (Mycologia, 1998)

Global climate change and ecosystem carbon storage: an experimental investigation of ecologically-mediated feedbacks to climate in montane meadows - S. R. Saleska (1998)

Adaptive significance of flower color and inter-trait correlations in an Ipomopsis hybrid zone - E. J. Melendez-Ackerman; Diane R. Campbell (Evolution, 1998)

Multiple paternity in fruits of Ipomopsis aggregata (Polemoniaceae) - Diane R. Campbell (American Journal of Botany, 1998)
Two different mechanisms can result in multiple paternity within fruits: deposition of a mixed pollen load due to carryover of pollen from flower to flower and multiple pollinator visits in close succession. I investigated the extent of multiple paternity within fruits of Ipompsis aggregata containing from 2 to 14 seeds. A paternity analysis based on ten polymorphic isozyme markers revealed multiple paternity in a minimum of 68% (based on simple paternity exclusion) and up to 100% (based on identification of the most likely father) of the multiseeded fruits. The estimated number of fathers increased with the number of seeds in a fruit, with an average of four sires, and up to nine sires, represented in a single fruit. To explore whether this level of multiple paternity could be explained solely by simultaneous deposition of a mixed pollen load, I constructed a computer simulation model based on previous measurements of movement patterns and pollen carryover by the hummingbird pollinators. Model predictions provided a good match to observed values for number of sires per fruit. Thus, the extensive pollen carryover in this species and consequent mixed pollen loads can explain the high levels of multiple paternity in natural populations.

The sublime in Rothko, Newman and Still - Cliff G. McMahon (St Andrews Research Repository (St Andrews Research Repository), 1998)
An important body of literature has accumulated (both primary and secondary sources) which necessitates that Rothko, Newman and Still be placed in the tradition of the sublime. In attempting this task, a background is established by a detailed summary of classical theory of the sublime in Longinus, Burke, Kant, and Nietzsche, followed by detailed summaries of major recent sublimist theory by Weiskel, Crowther, Lyotard, and Ferguson. Also, key ideas of Sartre and Jung are treated in order to round out the proper ideational context for a sublimicist analysis of these three painters. From this foundation, a working theory of the sublime is developed. Next, the painters’ crucial theoretic statement are analysed for their relevance to the sublime, and their programs and specific works are characterized in relation to theory of the sublime, and in relation to their treatments in criticism.
\nThe last two chapters treat two crucial contexts in which Rothko, Newman and Still are situated: The historically accumulated American tradition of the sublime in art and literature; and the general European context of modernism and postmodernism. Throughout the study, it is argued that various kinds of transcendence validate a set of various major modes of the sublime: The ideational, religious, moral, Burkean-Gothic, Kantian, Nietzschean, romantic, existential, Jungian-mythic, ontological, noble, and the sublime of light/color, along with negatives modes such as the comic, the ironic, the counter, the mock, and the merely rhetorical. It is argued, finally, that sublimicism will continue to be attractive for conservative, moderate, and radical points of view, that theory of the sublime has on-going power and validity into the future, and that between positive and negative modes, the positive will probably continue to dominate

Is the foraging behavior of Castor canadensis optimal? - ERIC R. Allen; M. Bonilla (1998)

Salinity Trends in Surface Waters of the Upper Colorado River Basin, Colorado - Norman E. Spahr; Nancy J. Bauch (Journal of Environmental Quality, 1998)
AbstractDissolved‐solids data collected in the Upper Colorado River Basin upstream from Cameo, Colorado, and in the Gunnison River Basin were analyzed for trends in flow‐adjusted dissolved‐solids concentrations and loads for water years 1970 to 1993, 1980 to 1993, and 1986 to 1993. Trend results for flow‐adjusted periodic dissolved‐solids concentrations for the Colorado River Basin upstream from Cameo, CO, generally were downward or no trend was indicated. Trends in flow‐adjusted monthly and annual dissolved‐solids loads primarily were downward or absent. These trend results partly agree with the downward trends reported by a previous investigation for the Colorado River near Cameo site. In the Gunnison River Basin, trends in flow‐adjusted dissolved‐solids concentrations and loads were not detected for more than one‐half of the site/analysis‐period combinations. Of the trends that were present, most indicated decreases in concentrations and loads rather than increases. In both the Colorado River Basin upstream from Cameo, CO, and the Gunnison River Basin, trends in flow‐adjusted dissolved‐solids concentrations and flow‐adjusted monthly and annual dissolved‐solids loads may be affected by a variety of factors. These include channel evolution and hydrologic variation, water quality and flow rate of groundwater discharges and springs, sample size and period of record of dissolved‐solids data, and changes in land use in the basin.

River: One Man's Journey down the Colorado, Source to Sea - Carolyn Maddux; Colin Fletcher (The Antioch Review, 1998)

Behavioral ecology and conservation biology - D. H. Van Vuren (1998)

Oviposition variation among Pieris napi due to increasing glucosinolate levels in cruciferous hostplants - S. Sabin (1998)

Ecological Feedbacks to Global Warming: Extending Results from Plot to Landscape Scale - John Harte (1998)

Effects of snow-melt timing on three high altitude Potentilla (Rosaceae) species: growth, reproduction, and distribution - K. A. Stinson (1998)

Life history consequences of social complexity: a comparative study of ground-dwelling sciurids - Kenneth B. Armitage; Daniel T. Blumstein (Behavioral Ecology, 1998)

Life histories and the strengths of species interactions: combining mortality, growth, and fecundity effects - M. A. McPeek; B. L. Peckarsky (Ecology, 1998)
Interactive effects of one species on another may simultaneously influence mortality, growth, and fecundity. To quantify the strength of an interaction between two species, we must therefore use techniques that integrate these various responses into estimates of overall effect. Demographic models of populations provide such a framework. Here we develop a demographic model describing the life history of a hemimetabolous insect to evaluate the relative importance of predator effects on mortality and growth of damselflies (Enallagma boreale) in fishless ponds and mayflies (Baetis bicaudatus) in trout streams. Previous experiments have shown that dragonfly predators in fishless ponds inflict direct mortality and cause reduced growth rates in Enallagma damselflies. Parameterization of the demographic model from these data show, however, that only the direct mortality effects of dragonflies should significantly influence damselfly population dynamics. This is because damselfly size at emergence does not influence adult female fecundity, so the effects of dragonflies on damselfly larval growth do not influence adult fecundity. Likewise, both trout and stonefly predators inflict mortality on larval Baetis mayflies and cause decreases in growth rates. However, our demographic analyses indicate that the growth effects of both predators should dominate the population-dynamic effects on Baetis. This is because size at emergence translates directly into adult fecundity in mayflies. We also present data suggesting that developmental responses to changes in environmental conditions (e.g., predator abundances, resource availabilities) differ between species depending on these same life history parameters. The biological significance of lethal vs. sublethal predator impacts must be evaluated in a demographic framework to identify whether alterations in growth rate, and the timing of and size at metamorphosis, significantly influence population dynamics. The demographic model used for any particular organism must be tailored to its life history, but the various impacts of interactions with other species can all be integrated into estimates of projected population growth that can then be readily compared among species with different life histories.

What plant ecologists can learn from zoology - Mary V. Price; Nickolas M. Waser (Perspectives in Plant Ecology, Evolution and Systematics, 1998)
How improved communication with zoology can enrich plant ecology is illustrated by some individual and collective actions that plant ecologists can take.

Survey of plant species diversity growing in the moss Aulacomnium sp - N. Doerr (1998)

Mineralogy of Tuckers Tunnel: Tuckerville, Hinsdale County, Colorado - Patrick E. Haynes; Paul F. Hlava (Rocks & Minerals, 1998)

Endangered mutualisms: the conservaiton of plant-pollinator interactions - C. A. Kearns; Nickolas M. Waser; David W. Inouye (Annual Review of Ecology and Systematics, 1998)

Location, Structure, and Contents of Burrows of Spermophilus Lateralis and Tamias Minimus, Two Ground Dwelling Sciurids - K. J. Bihr; Richard Alexander Smith (Southwestern Naturalist, 1998)

Sapsuckers at work - G. C. Daily; P. R. Ehrlich (Whole Earth, 1998)

A life to remember - J. D. Hallahan (1998)

Pollination, angiosperm speciation, and the nature of species boundaries - Nickolas M. Waser (Oikos, 1998)
Despite much recent research on pollination, we have amassed relatively little hard information about how animal pollinators contribute to angiosperm speciation and species distinctiveness. We usually assume that pollinators make important contributions by specializing on plant species and providing differences upon which plants specialize. But evidence for generalization in many plant-pollinator interactions calls this assumption into question. Generalization makes strong floral isolation unlikely during and after the speciation process, and is seen by some workers as problematical for a scenario of pollinator-mediated disruptive selection leading to species formation. The time is ripe to initiate several lines of further research. It will be valuable to characterize selection on plants more carefully at various spatial scales to understand whether different suites of pollinators can affect consistent selection in different directions on floral characteristics. Similarly, it will be valuable to explore how reproductive isolation arises within and among populations, races, and higher taxa of plants. Even if they are not strong agents of floral isolation, pollinators may contribute to the evolution of reproductive isolation in other ways, which largely remain to be discovered. One possibility is that reproductive isolation evolves more or less independently of diversification in reproductive characteristics. If so, floral adaptation may not be tightly coupled with the formation of biological species in angiosperms, as is often supposed.

Shifts in the altitudinal distribution of bumblebees near Gothic, Colorado - E. Long (1998)

Status and Trends of the Endangered Colorado Squawfish in the Upper Colorado River - Doug B. Osmundson; Kenneth P. Burnham (Transactions of the American Fisheries Society, 1998)
Status of the Colorado River population of the endangered Colorado squawfish Ptychocheilus lucius (recently renamed the Colorado pikeminnow) was investigated by (1) estimating adult numbers, (2) evaluating frequency of reproduction and recruitment, (3) identifying trends via changes in size structure over time, and (4) examining historical accounts for clues to former abundance. Adults and subadults were systematically captured from 278 km of river during 1991–1994. Larvae and age-0 fish were systematically sampled in two reaches during 1986–1994. Estimated number of adults in the upper 98 km averaged 253 individuals; estimated annual adult survival rate was 0.86. In the lower 181 km, estimates of subadults and adults combined averaged 344 individuals. A sizable pulse of subadults 300–400 mm long found in the lower reach in 1991 were from three year-classes, 1985–1987. By 1992, these were distributed throughout the river. Although catch rates of larger adults did not increase significantly in the upper reach during 1991–1994, catch rates of fish less than 550 mm long increased fivefold. Size-frequency analysis of lower-reach fish indicated the 1985–1987 cohorts were the largest produced since before 1977, and no similarly strong year-classes were produced subsequently. Estimated years of origin of these recruiting fish coincided with years of higher-than-average catch rates of larvae and age-0 fish in the upper reach and catch rates in subsequent years there were comparatively low. Very few individuals less than 450 mm long were found in the upper reach during the past 15 years, suggesting that recruitment there is from colonization from the lower reach. In contrast, significant numbers of fish less than 400 mm in total length occurred in the upper reach during the mid-1970s. Abundance appears much lower than suggested in historical accounts. Low adult numbers and sporadic pulses of recruitment may make this population vulnerable to extirpation. Though adult survival rate is probably fairly constant, recruitment is highly variable and may represent the most important demographic factor to population persistence.

A 32-year demography of yellow-bellied marmots (Marmota flaviventris) - O. A. Schwartz; D. H. Van Vuren; Kenneth B. Armitage (J Zool London, 1998)
Yellow-bellied marmots Marmota ¯aviventris in the East River Valley of Colorado were live-trapped and individually marked annually from 1962 through 1993. These pooled data were used to produce a demography and life table for these years. Females had signi®cantly better survivorship than males beyond the ®rst-year age class, and the sex ratio became progressively female biased. The major mortality factors of predation and unsuccessful hibernation acted evenly on all age classes as shown by the constant rates of survivorship. The rate of senescence indicated that the probability of mortality did not increase with age. Females produced litters from ages 2 to 10 years. Mean litter size was 4.1 and did not differ among age classes. The female generation length of 4.49 years was 2.4 times the life expectancy and the median survivorship. The net reproductive rate (Ro) was 0.67, yet the population did not continually decline; adjustments to these data increased Ro to 0.85. Reproductive values (Vx) were approximately equal across the reproductive age classes. The polygynous mating system is both cause and effect of the demography. Marmot population size is affected by weather factors that in¯uence reproduction and survival, by predation, and by movement into and out of the study area. Key words: yellow-bellied marmot, demography, life table, sex ratio, Marmota ¯aviventris

Fitness and community consequences of avoiding multiple predators - A. R. McIntosh; B. L. Peckarsky (Oecologia, 1998)
This study demonstrates the importance of considering multiple predators when measuring direct sublethal effects of predators on prey fitness and indirect effects on lower trophic levels, and attributes the non-additivity of effects of fish and stoneflies on mayfly growth to an interaction modification whereby trout odour reduced the impact of stone flies on Baetis behaviour.

Field Estimation of food-web complexity in a sub-alpine meadow - E. Garcia (1998)

A test of the acoustic adaptation hypothesis in four species of marmots - J. C. Daniel; Daniel T. Blumstein (Animal Behavior, 1998)
The evidence did not support the acoustic adaptation hypothesis for these marmot species, and factors other than maximizing long-distance transmission through the environment may be important in the evolution of species-specific marmot alarm calls.

Allelopathic effects of Serphidium tridentatum upon two species of annuals - A. Zawacki; J. Baxter (1998)

Extrapolating from individual behavior to populations and communities in streams - S. D. Cooper; A. R. McIntosh; B. L. Peckarsky (Journal of the North American Benthological Society, 1997)
Biological processes, such as predator-prey or competitive interactions, occur at multiple spatial and temporal scales, but their impacts on the distribution, abundance, and fitness of organisms may only be detectable at some scales. This is because 1) small scale (local) processes may be constrained by large-scale (regional) processes, 2) the influence of organism movement changes with spatial scale, and 3) multiple small-scale processes may interact and produce variation that obscures large-scale patterns. Most ecologists would like to know the relevance of small-scale observations and experiments for large-scale patterns and processes acting over long time periods. In this paper we consider whether patterns of individual behavior translate in a straightforward way to patterns in population dynamics, community structure, or individual fitness at larger spatial and longer temporal scales. We illustrate our discussion with data from communities living in high altitude streams in western Colorado, coastal streams in southern California, and streams on the South Island of New Zealand. We describe patterns of individual behavior including selective predation, predator-avoidance behavior, and competitive interactions. Our examples indicate that large scale patterns of distribution and abundance of organisms sometimes deviate from those expected from patterns of individual behavior. We hypothesize that such discrepancies are often due to multiple confounding factors, including abiotic disturbances, that have effects on populations and communities at larger scales. Similarly, our data illustrate that present behaviors may not have measurable fitness consequences over longer time scales. We emphasize that only by studying all life history stages of organisms with complex life cycles can we interpret the long-term fitness consequences of individual behaviors. We conclude that our ability to extrapolate from individual behaviors to populations and communities in streams will improve when we consider the repercussions of individual behaviors and environmental factors over broader spatial and temporal scales.

Reproductive allocation from reserves and income in butterfly species with differing adult diets - Carol L. Boggs (Ecology, 1997)
Allocation of stored and incoming nutrients to reproduction determines an organism’s age-specific fecundity curve. In holometabolous insects, differences among species in the shape of the curve are correlated with differences in the potential importance of adult food to reproduction. I examined allocation patterns underlying this association. Specific changes throughout life in body mass and reproductive effort were predicted to result from use of stored vs. incoming nutrients for reproduction and other metabolic needs at each age. Data for three nymphalid butterfly species, Euphydryas editha, Speyeria mormonia, and Heliconius charitonius, were compared with the predictions. These three species differ in adult diet and fraction of oocytes mature at adult emergence (hence, potential for adult nutrients to be used to make eggs), with E. editha showing the least potential for use of adult nutrients in egg production and H. charitonius showing the greatest potential. For all three species, body mass declined with age, although nonlinearly for E. editha. This indicated that metabolic expenditures were greater than intake at all ages, and that a constant fraction of stored nutrients was allocated to reproduction and other metabolic uses at each age for E. editha. Reproductive effort also declined with age for all three species. The specific patterns seen suggested that incoming nutrients may be stored, to some extent, early in life and then used late in life by both S. mormonia and H. charitonius. The similarity between S. mormonia and H. charitonius is rather surprising, given the qualitative differences in adult diet and suggests either that qualitative age-specific allocation patterns for incoming vs. stored nutrients may be independent of adult diet quality, or that the observed patterns are constrained by phylogenetic relatedness of these two species.

Analyzing pollinator-mediated selection in a plant hybrid zone: hummingbird visitation patterns on three spatial scales - E. J. Melendez-Ackerman; Nickolas M. Waser; Diane R. Campbell (American Naturalist, 1997)
Clines across hybrid zones can be produced by several forms of natural selection. We illustrate an approach to studying pollinator-mediated selection in plant hybrid zones, using two species of Ipomopsis (Polemoniaceae) as a model system. We measured visitation to flowers in natural and experimental populations by two major types of pollinators, hummingbirds and hawkmoths, at up to three different spatial scales. Using measures of pollinator visitation, we calculated phenotypic selection gradients and characterized the form of selection in the hybrid zone. Hummingbirds overvisited Ipomopsis aggregata compared with Ipomopsis tenuituba and morphological hybrids at all spatial scales, especially the largest scale of kilometers. These responses may depend in part on the presence of other hummingbird-visited plants in the community. Hummingbird behavior produced directional selection favoring wide corolla tubes and intense red coloration. Hawkmoths, in contrast, overvisited plants with narrow corolla tubes. When both types of pollinators were present, corolla width experienced disruptive selection, consistent with a model of hybrid disadvantage. In the natural hybrid zone, however, hawkmoths are rare participants. In most years plants experience visitation from hummingbirds alone. Thus, selection by pollinators usually fits an advancing wave model in which traits characteristic of I. aggregata are favored everywhere. Modeling the evolution of clines in response to such pollinator-mediated selection will require further theoretical development that allows for selection intensity to vary with spatial scale and with the abundance of unrelated plants visited by the same pollinators.

Does sociality drive the evolution of communicative complexity? A comparative test with ground-dwelling sciurid alarm calls - Kenneth B. Armitage; Daniel T. Blumstein (American Naturalist, 1997)
While sociality has been hypothesized to drive the evolution of communicative complexity, the relationship remains to be formally tested. We derive a continuous measure of social complexity from demographic data and use this variable to explain variation in alarm repertoire size in ground-dwelling sciurid rodents (marmots, Marmota spp.; prairie dogs, Cynomys spp.; and ground squirrels, Spermophilus spp.). About 40% of the variation in alarm call repertoire size was explained by social complexity in the raw data set. To determine the degree to which this relationship may have been influenced by historical relationships between species, we used five different phylogenetic hypotheses to calculate phylogenetically independent contrasts. Less variation was significantly explained in contrast-based analyses, but a general positive relationship remained. Social complexity explained more variation in alarm call repertoire size in marmots, while sociality explained no variation in repertoire size in prairie dogs and no variation in phylogenetically based analyses of squirrels. In most cases, substantial variation remained unexplained by social complexity. We acknowledge that factors other than social complexity, per se, may contribute to the evolution of alarm call repertoire size in sciurid rodents, and we discuss alternative hypotheses. Our measure of social complexity could be used by other researchers to test explicit evolutionary hypotheses that involve social complexity.

Alarm calling in yellow-bellied marmots: I. The meaning of situationally variable alarm calls - Kenneth B. Armitage; Daniel T. Blumstein (Animal Behaviour, 1997)
Yellow-bellied marmots, Marmota flaviventris were reported to produce qualitatively different alarm calls in response to different predators, but there was significant individual variation in call structure, but acoustic parameters that were individually variable were not used to communicate variation in risk.

Maintenance of polymorphism promoted by sex-specific fitness payoffs - Howard Whiteman (Evolution, 1997)
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Biodiversity and ecosystem function: correlations among aboveground biomass, species richness, and soil organic matter - M. L. Holman (1997)

Ants, competition, and diversity: part one - K. K. Ingram (1997)

Introduced plant species in Gothic, Colorado: invasive or harmless? - A. McCarthy; C. Gubser (1997)

On the implications of species-area relationships for endemism, spatial turnover, and food web patterns - A. P. Kinzig; John Harte (Oikos, 1997)
Consequences of species-area relationships (SARs) of the form S = cA are derived. One consequence is an endemics-area relationship (EAR); it is of the same power-law form as the SAR but with an exponent z' that is a function only of z and that always exceeds unity. An explicit formula is derived for the dependence of species turnover in space on census plot size, interplot distance, and the SAR exponent z; this formula can be used to determine z over spatial scales that are too large to permit direct estimate of z by censusing of nested patches. The areal dependence of link-species patterns observed in food webs is also examined; SARs are shown to imply the approximate, but not exact, area-independence of link-species relationships of the form L = kSy, where L is the number of trophic links and y < 2. A relationship between the average range of species in a habitat patch and the exponent z is also derived, leading to the result that average range is a decreasing function of both patch area and z.

Harry Gunnison Brown's Advocacy - Christopher K. Ryan (The American Journal of Economics and Sociology, 1997)
Abstract. Harry Gunnison Brown's fifty plus years of active advocacy of land value taxation are reviewed in the light of two recent articles. One indicates a waning interest and even understanding of Brown's chosen cause while the other demonstrates quite the opposite: the persistence and relevance of land value taxation. Brown's strategies are examined, drawing on his correspondence as well as his publications. It is suggested that evaluation of Brown's success or failure is a moot question in the sense that there was no one with whom to compare him.

ALTERED STREAMFLOW AND SEDIMENT ENTRAINMENT IN THE GUNNISON GORGE1 - John G. Elliott; Randolph S. Parker (JAWRA Journal of the American Water Resources Association, 1997)
ABSTRACT: The Gunnison River in the Gunnison Gorge is a canyon river where upstream dams regulate mainstem discharge but do not affect debris‐flow sediment supply from tributaries entering below the reservoirs. Regulation since 1966 has altered flood frequency, streambed mobility, and fluvial geomorphology creating potential resource‐management issues. The duration of moderate streamflows between 32.3 and 85.0 m3/s has increased threefold since 1966. This, along with flood‐peak attenuation, has facilitated fine‐sediment deposition and vegetation encroachment on stream banks. The Shields equation and on‐site channel geometry and bed‐material measurements were used to assess changes in sediment entrainment in four alluvial reaches. Sand and fine gravel are transported through riffle/pool reaches at most discharges, but the cobbles and boulders composing the streambed in many reaches now are infrequently entrained. Periodic debris flows add coarse sediment to rapids and can increase pool elevation and the streambed area affected by backwater and fine‐sediment accumulation. Debris‐flow supplied boulders accumulate on fans and in rapids and constrict the channel until reworked by larger floods. The response to streamflow‐régime changes in the Gunnison Gorge could serve as an analog for alluvial reaches in other regulated canyon rivers.

Concentration and color preference in nectar feeding birds - M. S. Adams (1997)

A long-term study on the effects of temporal variation in precipitation on the flowering behavior of Androsace septentrionalis L. (Primulaceae) - W. Lee (1997)

Hummingbird behavior and mechanisms of selection on flower color in Ipomopsis - E. J. Melendez-Ackerman; Nickolas M. Waser; Diane R. Campbell (Ecology, 1997)

Analysis of pollinator foraging: tests for non-random behavior - Kenneth L. Jones (Functional Ecology, 1997)
1. A standardized protocol for analysing the behaviour of pollinators foraging on more than one plant type (species or morph) is needed. 2. A protocol is presented in which the first step is to test whether foraging trips are homogeneous in the frequency of visits to each plant type, or whether there are two or more groups of pollinators with different foraging preferences. 3. Tests for foraging preference and constancy in the sequence of plants visited then should be made separately for each homogeneous group. 4. A hypothetical example is given in which ignoring heterogeneity of preference would lead to the acceptance of a false null hypothesis of random behaviour. 5. A real example is given in which heterogeneity of preference was the only non‐random aspect of pollinator behaviour (no significant positive constancy or overall preference), while transfer of powdered dye particles (pollen analogues) was assortative among floral morphs. 6. Heterogeneity of preference is probable, as many factors may cause individual pollinators to forage differently on the same patch of plants, and may be sufficient to produce non‐random pollen transfer among plant morphs.

Growth and Survival of Colorado Squawfish in the Upper Colorado River - T. E. Mourning; R. J. Ryel; Doug B. Osmundson (Transactions of the American Fisheries Society, 1997)
Growth and adult survival rates were estimated for the endangered Colorado squawfish Ptychocheilus lucius inhabiting the upper Colorado River by using data from fish captured during 1990–1995. Mean annual growth rates of fish aged 3–6 years ranged from 32.2 (age 6) to 82.0 (age 3) mm/year. Growth rates for older fish were highest for fish 400–449 mm total length, TL, (42.7 mm/year) and declined to 19.8 mm/year for fish 500–549 mm TL. Fish 550 mm and longer grew an average 9.5 mm/year. Survival rates for fish 550 mm and longer were estimated by comparing measured size distributions with simulated stable age and size distributions; these ranged from 0.83–0.87, with the best fit at 0.85. Though lack of historical data precludes comparisons with past growth and survival rates, our data serve as a baseline for future population monitoring efforts.

Lesquerella vicina (Brassicaceae), a New Species from the Uncompahgre River Valley in Western Colorado - Reed C. Rollins; James L. Reveal (Novon, 1997)
John L. Anderson, James L. Reveal, Reed C. Rollins, Lesquerella vicina (Brassicaceae), a New Species from the Uncompahgre River Valley in Western Colorado, Novon, Vol. 7, No. 1 (Spring, 1997), pp. 9-12

Distribution of caddisfly larvae according to location and presence of predators in high mountain ponds - Laura Warman (1997)

Dynamics of reproductive allocation from juvenile and adult feeding: radiotracer studies - Carol L. Boggs (Ecology, 1997)
Nutrients used in reproduction may come from adult feeding or reserves stored from the juvenile stage. The dynamics of allocation from these sources are predicted to differ among nutrient types, depending on the relative availability of each nutrient type from adult and juvenile feeding. Using radiotracer techniques, I examined reproductive allocation of glucose and amino acids from adult and juvenile sources in two nymphalid butterflies, Euphydryas editha and Speyeria mormonia. The species used were intermediate in expected importance of adult nutrients to egg production, with abundant carbohydrates but few nitrogenous compounds available from the adult diet. As predicted, for compounds abundantly available in the adult diet, incoming nutrients were used in preference to stored nutrients. For compounds present in low amounts in the adult diet, juvenile reserves were used throughout adult life, although adult sources were used if available. Nutrients received by the female from the male at mating, although expected to be treated as stored reserves, were immediately used in egg production. Thus, restriction of adult or juvenile feeding may cause different nutrient types (e.g., carbohydrates, nitrogenous compounds) to become limiting to reproduction. These results are consistent with earlier allocation studies examining age-specific changes in body mass and reproductive effort, and the effects on fecundity of quantitative adult food reduction. The work has implications for understanding the evolution of nutrient types donated by males to females, the effects of a holometabolous lifestyle on age-specific fecundity, and the effects of using stored reserves vs. income in reproduction. The present results allow further predictions concerning effects of food supply perturbation on fecundity and, hence, population dynamics, and suggest ways in which species and individuals will differ in sensitivity to those perturbations.

Changes in water relations for leaves exposed to a climate-warming manipulation in the Rocky Mountains of Colorado - M. E. Loik; John Harte (Environmental and Experimental Biology, 1997)

Terrestrial ecosytem feedbacks to global climate change - B. J. DeAngelo; D. A. Lashof; S. R. Saleska; John Harte (Annual Review Energy Environment, 1997)
Anthropogenic greenhouse gases are expected to induce changes in global climate that can alter ecosystems in ways that, in turn, may further affect climate. Such climate-ecosystem interactions can generate either positive or negative feedbacks to the climate system, thereby either enhancing or diminishing the magnitude of global climate change. Important terrestrial feedback mechanisms include CO2 fertilization (negative feedbacks), carbon storage in vegetation and soils (positive and negative feedbacks), vegetation albedo (positive feedbacks), and peatland methane emissions (positive and negative feedbacks). While the processes in- volved are complex, not readily quantifiable, and demonstrate both positive and negative feedback potential, we conclude that the combined effect of the feedback mechanisms reviewed here will likely amplify climate change relative to current projections that have not yet adequately incorporated these mechanisms. CONTENTS

Pollinators, Flowering Plants, and Conservation Biology - C. A. Kearns; David W. Inouye (BioScience, 1997)
M ore than a century ago, Darwin (lg59) observed that number of bumblebees in any district depends in a great measure upon the number of fieldmice, which destroy their combs and nests ... che number of mice is largely Jependent, as everyone knows, on the number of cats .. .it is quite credible that the presence of a feline animal in large numbers in a district might uetermine, through the intervention first of mice and then of bees, the frequency of certain flowers in that district! (p. -125). Dar\'{in recoglllzed the importance of interactions among organisms, specifically the role that pollinators play as links in communities. Yet, almost 140 years later, our understanding of pollination interactions is still rudimentary. The extent of dependence and linkage in pollination sys-

Time of day and visitation affects on nectar volumes throughout the day in Aquilegia caerulea - K. Jenderseck (1997)

Differential predation of mayfly larvae and damselfly larvae by tiger salamanders - G. S. Keegan; Curtis Martin (1997)

Effects of experimental manipulation of inflorescence size on pollination and pre-dispersal seed predation in the hummingbird-pollinated plant Ipomopsis aggregata - Richard S. Mitchell; Alison K. Brody (Oecologia, 1997)

Aliens mine peanuts: root-elongation tests and the effects of heavy metals on Carex at the Peanut Mine, Crested Butte, CO) - J. L. Hayes; R. Roland (1997)

Community composition in mountain ecosystems: climatic determinants of montane butterfly distributions - Dennis D. Murphy; Carol L. Boggs (Global Ecology and Biogeography Letters, 1997)
Carol L. Boggs, Dennis D. Murphy, Community Composition in Mountain Ecosystems: Climatic Determinants of Montane Butterfly Distributions, Global Ecology and Biogeography Letters, Vol. 6, No. 1, Mountain Ecology: Organism Responses to Environmental Change (Jan., 1997), pp. 39-48

Social interactions and natal dispersal of young golden-mantled ground squirrels (Spermophilus lateralis) - K. Jenderseck (1997)

Helianthella-ant mutualism - G. McCracken (1997)

Specialization and foraging ergonomics in a subalpine bumblebee Bombus appositus (Hymenoptera: Apidae) - M. C. Jost (1997)

Natural variation in pollinator composition and services: effects on the reproductive success of Ipomopsis aggregata - M. M. Mayfield (1997)

Response of mayfly larvae to fish odor: development of a bioassay to test chemical response - K. Maly (1997)

Insect numbers and diversity along three roadsides of different ages - C. Gubser (1997)

The high life: a subalpine fir and Englemann spruce community in an avalanche zone - J. P. Oliva; S. Ochs (1997)

Pollinator choice of flower size and sexual morph in Geranium richardsonii - A. Drew (1997)

Alarm calling in yellow-bellied marmots: II. The importance of direct fitness - J. Steinmetz; J. C. Daniel; Kenneth B. Armitage; Daniel T. Blumstein (Animal Behaviour, 1997)
Alarm calling in group-living yellow-bellied marmots is a form of direct parental care and inclusive fitness, broadly defined, is of little importance for the maintenance of alarm calling.

A look at leaf litter diversity in a grazed and non-grazed aspen grove - J. L. Hayes (1997)

Effects of manure on germination of Bromus tectorum in contaminated mine soil - R. Roland (1997)

Phenomenon of a moist environment shrub growing in dry conditions: why is it there? - Curtis Martin (1997)

The effects of road proximity on pollinator visit to Mertensia ciliata - A. McCarthy (1997)

Competitive foraging interactions in a sub-alpine ant community - B. Peters (1997)

What attracts snipe flies (Diptera: Rhagionidae, Symphoromyia Frauenfeld)? The effects of CO2 and mammalian temperature - H. Song (1997)

Cyclic Colonization in Predictably Ephemeral Habitats: A Template for Biological Control in Annual Crop Systems - S. A. Wissinger (Biological Control, 1997)
It is argued that ACSs are “predictably ephemeral” habitats that present a selective environment that is different from that commonly envisioned for disturbed or early successional habitats, and therefore, effective biological control strategies in ACSs must include a landscape ethic that provides an abundance of permanent habitats that can act as reservoirs for indigenous and introduced natural enemies.

The effect of mermithid parasitism on predation of nymphal Baetis bicaudatus (Ephemeroptera) by invertebrates - S. A. Vance; B. L. Peckarsky (Oecologia, 1997)
A number of hypotheses are presented to explain why the parasite causes increased predation on its host, including the large size of the parasite affecting the sensory abilities of the host, the larger energetic costs of escape behavior for parasitized individuals, and natural selection from fish predation against drifting behavior by Parasitized individuals.

Olfactory versus visual cues in a floral mimicry system - B. A. Roy; Robert A. Raguso (Oecologia, 1997)
It is found that pseudoflower fragrance can attract visitors by itself, and the ability of insects to differentiate pseudoflowers from true flowers by their fragrance may be important in the evolution of the mimicry system.

Inter- and intraspecific variation in the acoustic habitats of three marmot species - J. C. Daniel; Daniel T. Blumstein (Ethology, 1997)
Closely related species often have remarkably different vocalizations. Some of the variation in acoustic structure may result from species adapting their calls to maximize transmission through their acoustic environ- ments. We document the relative magnitude of inter- and intraspecific variation in acoustic transmission properties of the habitats of three closely related marmot species to study the relative importance that the acoustic environment may have played in selecting for species-specific marmot alarm calls. We used spectrogram cor- relation to quantify the degree to which pure tones and alarm calls changed as they were broadcast through matmot home ranges to describe the acoustic habitats of golden (M1. candata aurea), yellow-bellied (M. flaviventris), and alpine (Af. marmota L.) marmots. Species lived in quantifiably different acoustic habitats. One analysis partitioned variation between species and between marmot social groups (nested within species). We found significant interspecific variation in the acoustic transmission fidelity of the three species’ habitats and insignificant intraspecific variation between social groups. Further analysis of a larger sample of alarm calls broadcast through golden marmot social groups found significant intraspecific variation. Interspecific variation greater than intraspecific variation suggests that variable acoustic habitats may be responsible for at least some of the interspecific variation in alarm call structure. This is the first study to use spectrogram correlation to describe habitat acoustics. We discuss aspects of the method that may be useful for others seeking to quantify habitat acoustics. Corresponding author: Daniel T. BLUMSTEIN, Department of Systematics and Ecology, University of Kansas, Lawrence, KS 66045 USA. Email: marmota@falcon.cc.ukans.edu

Plant and insect diversity and abundance: resilience in response to human disturbance - Horace G. Smith; K.S. Smith (1997)

Effect of the presence of aphids (Aphididae) on oviposition in the pre-dispersal seed predator Hylemya (Delia) spp. on the host plant Polemonium foliossissimum (Polemoniaceae) - U. Lang (1997)

Effects of pre-dispersal selection on offspring growth and survival in Erythronium grandiflorum - M. B. Cruzan; James D. Thomson (Journal of Evolutionary Biology, 1997)
AbstractEffects of pre‐seed‐dispersal processes on offspring vigor were examined in Erythronium grandiflorum using manipulations of the number of pollen donors contributing to the pollen pool and comparisons of means and variances in offspring growth measurements. There were no effects of the number of donors on measures of pollen‐tube growth, ovule abortion, seed set, mean seed weight, or seedling germination. Seeds from pollinations with only one donor produced corms that averaged 5% lighter after one season of growth and had lower overall survival after three years compared to corms from pollinations with either three or ten donors. Patterns of within‐ and among‐family variance estimates for the different treatments were consistent with the hypothesis that less‐vigorous offspring were eliminated prior to seed dispersal in the multiple‐donor treatments. The difference in the growth of offspring from different treatments was apparently not due to pollen competition because pre‐zygotic attrition of pollen tubes led to incomplete fertilization of ovules. Results from this study suggest that post‐fertilization abortion of less‐vigorous progeny, perhaps as a consequence of early‐acting inbreeding depression, is responsible for the increase in the average vigor of offspring from multiply‐sired fruits.

Colony growth and reproduction in the ant species Formica neorufibarbis - Ian Billick (1997)

Genetic and environmental variation in life-history traits of a monocarpic perennial: a decade-long field experiment - Diane R. Campbell (Evolution, 1997)
Directional and stabilizing selection tend to deplete additive genetic variance. On the other hand, genetic variance in traits related to fitness could be retained through polygenic mutation, spatially varying selection, genotype-environment interaction, or antagonistic pleiotropy. Most estimates of genetic variance in fitness-related traits have come from laboratory studies, with few estimates of heritability made under natural conditions, particularly for longer lived organisms. Here I estimated additive genetic variance in life-history characters of a monocarpic herb, Ipomopsis aggregata, that lives for up to a decade. Experimental crosses yielded 229 full-sibships nested within 32 paternal half-sibships. More than 5000 offspring were planted as seeds into natural field sites and were followed in most cases through their entire life cycle. Survival showed substantial additive genetic variance (genetic coefficient of variation ≈ 54%). Small differences at seedling emergence were magnified over time, such that the genetic variability in survival was only detectable by tracking the success of offspring for several years starting from seed. In contrast to survival, reproductive traits such as flower number, seeds per flower, and age at flowering showed little or no genetic variability. Despite relatively high levels of additive genetic variation for some life-history characters, high environmental variance in survival resulted in very low heritabilities (0-9%) for all of these characters. Maternal effects were evident in seed mass and remained strong throughout the lengthy vegetative period. No negative genetic correlations between major components of female fitness were detected. Mean corolla width for a paternal family was, however, negatively correlated with the finite rate of increase based on female fitness. That negative correlation could help to maintain additive genetic variance in the face of strong selection through male function for wide corollas.

Effects of pollinators, herbivores, and seed predators on flowering phenology - Alison K. Brody (Ecology, 1997)
The evolution of flowering phenology has most often been examined in light of one set of organisms, namely pollinators. However, the patterns of flowering phenology observed in nature are likely to reflect evolutionary compromises in response to a variety of selective forces. Two of the most important potentially opposing selective forces that could elicit such a compromise are pollinators and pre-dispersal seed predators. Using a case study from my own work on the pollinators and pre-dispersal seed predators of two members of the Polemoniaceae, Polemonium foliosissimum and Ipomopsis aggregata, I show that the outcome of selective pressures is not always predictable by examining one group of organisms or another. In addition, the outcome of separate and combined selective pressures is variable among years. Thus I show that only by considering all organisms that affect the fitness of a plant may we gain a complete understanding of the evolution of floral traits. I argue that we must account for both geographical and temporal variation in assessing the ecological and evolutionary importance of interacting organisms.

Human roadside disturbance and natural avalanche disturbance: a richness and diversity comparison - D. Parson (1997)

The effects of large invertebrates on the development of cannibal morphology in the tiger salamander, Ambystoma tigrinum nebulosum - R. T. Cargille (1997)

Nature's Services: Societal Dependence on Natural Ecosystems - A. Wilcox; John Harte (1997)

Richness and distribution of insects on a slope frequently disturbed by avalanches - Laura Warman (1997)

Patterns of color and nectar variation across an Ipomopsis (Polemoniaceae) hybrid zone - E. J. Melendez-Ackerman (American Journal of Botany, 1997)
Hybridization may uncouple adaptive trait combinations that are present in parental species. I studied variation in flower color and reward quality across a hybrid zone of Ipomopsis aggregata and I. tenuituba. Individuals from hybrid populations showed considerable variation in flower color using corolla reflectance measurements. Flower spectra of such individuals were either intermediate or else resembled those flowers from the parental species. Ipomopsis aggregata populations had consistently higher nectar production rates and higher nectar standing crops than either I. tenuituba or hybrids. Ipomopsis aggregata flowers also produced more dilute nectar than those of hybrids and I. tenuituba, but the actual concentration values were quite variable among populations of the same type. Overall, the nectar quality of hybrid flowers most resembled that of I. tenuituba flowers. Based on the observed interpopulation patterns of color‐reward associations in this hybrid zone, pollinators should be able to discriminate against I. tenuituba and hybrid populations and against most individuals within hybrid populations. However, they may visit those hybrids that resemble the most rewarding flower type (I. aggregata). The results emphasize the need for studies that address how hybridization affects subsequent plant fitness and the evolutionary dynamics of the species involved.

Effects of interspecific pollen transfer between Ipomopsis aggregata and Castilleja linaerifolia (a case study of I. aggregata) - M. Alfaro (1997)

The evolution of specialization in lycaenid butterfly-ant mutualisms - A. M. Fraser (1997)

Reproductive resource allocation in Delphinium nelsonii - A. Alvarado (1997)

Genetic correlation between biomass allocation to male and female functions in a natural population of Ipomopsis aggregata - Diane R. Campbell (Heredity, 1997)

Case material choice by caddisfly larvae in the presence of a predator - J. Gifford; S. A. Lopez (1997)

Why red flowers are not invisible to bees - L. Chittka; Nickolas M. Waser (Israel Journal of Plant Sciences, 1997)
A pervasive idea among pollination biologists is that bees cannot see red flowers. This idea has led many workers to assume that red coloration is an adaptation by which flowers exclude bees as visitors. However, recent empirical and theoretical evidence strongly supports the alternative view, that red flowersarevisible to bees. Our purpose is to marshal this evidence from physiology, behavior, and ecology. First, we define the spectral boundary between orange and red, and show that the visual spectrum of all bee species studied to date extends enough into long wavelengths to provide sensitivity to red light. Such sensitivity differs from the ability to discriminate different monochromatic lights, and we argue that bees will be unable to discriminate such lights above about 550 nm. Second, we point out that flowers do not reflect monochromatic lights. Instead many of them, particularly those that appear red, orange, yellow, and white to humans, have reflectance patterns that are essentially step functions. We predict that bees should be able to discriminate such reflectance patterns over a range of 550–650 nm, since reflectance functions with steps at such wavelengths will occupy different loci in bee color space and thus be distinguishable. In this sense, bees should distinguish between green-, yellow-, orange-, and red-reflecting objects, even if these do not reflect in shorter wavelengths (including UV). A behavioral experiment shows that bumblebees can indeed perform this task. Third, we present information on the spectral reflectance of some typical “red” flowers, combined with field observations of bee visitation to such flowers. We end with a preliminary reassessment of the adaptive significance of red flower coloration, using North American “hummingbird” flowers as an example; we also stress some of the pitfalls facing evolutionary biologists who continue to assume that bees are blind to red objects.

Trapline foraging by bumble bees: II. Definition and detection from sequence data - M. Slatkin; B. A. Thomson; James D. Thomson (Behavioral Ecology, 1997)
Trapline foraging—repeated sequential visits to a series of feeding locations—presents interesting problems seldom treated in foraging models. Work on traplining is hampered by the lack of statistical, operational approaches for detecting its existence and measuring its strength. We propose several statistical procedures, illustrating them with records of interplant flight sequences by bumble bees visiting penstemon flowers. An asymmetry test detects deviations from binomial expectation in the directionality of visits between pairs of plants. Several tests compare data from one bee to another frequencies of visits to plants and frequencies of departures to particular destinations are compared using contingency tables; similarities of repeated sequences within bees are compared to those between bees by means of sequence alignment and Mantel tests. We also compared observed movement patterns to those generated by null models designed to represent realistic foraging by non-traplining bees, examining: temporal patterns of the bee's spatial displacement from its starting point using spectral analysis; the variance of return times to particular plants; and the sequence alignment of repeated cycles within sequences. We discuss the different indications and the relative strengths of these approaches

The effect of colors: what attracts snipe flies (Diptera: Rhagionidae, Symphoromyia Frauenfeld)? - H. Song (1997)

Alien and endemic plant species richness and diversity in relation to disturbance at Rosy Point, Gothic, CO - C. Silapaswan (1997)

Male reproductive success and variation in fruit and seed set in Aquilegia carerulea (Ranunculaceae) - J. Brunet (Ecology, 1996)

Effects of human-made trails on local vegetative diversity - P. Higuera (1996)

Biodiversity in marmots - Kenneth B. Armitage; Kenneth B. Armitage; Kenneth B. Armitage (1996)

Resource partitioning and per-flower foraging efficiency in two bumblebee species - L. Graham; Kenneth L. Jones (American Midland Naturalist, 1996)

Growth and foraging consequences of facultative paedomorphosis in the tiger salamander, Ambystoma tigrinum nebulosum - W. S. Brown; Howard Whiteman; S. A. Wissinger (Evolutionary Ecology, 1996)

Feedbacks, thresholds and synergies in global change: population as a dynamic factor - John Harte (Biodiversity and Conservation, 1996)

High-temperature tolerance of Artemisia tridentata and Potentilla gracilis under a climate change manipulation - M. E. Loik; John Harte (Oecologia, 1996)

Adaptation at specific loci. VI. Divergence vs parallelism of polymorphic allozymes in molecular function and fitness-component effects among Colias species (Lepidoptera:Pieridae) - K. Donohue; P. A. Carter; W. B. Watt (Molecular Biology and Evolution, 1996)

Biodiversity in marmots (1996)

Vascular plant species of talus slope and their dispersal patterns - M. Bateman (1996)

Foraging and vigilance behavior of social and solitary female marmots - G. Graham (1996)

A new horizon for biological field stations and marine laboratories - S. A. Lohr; J. S. Clegg; P. G. Connors; J. A. Stanford; S. A. Lohr; J. A. Stanford (Trends in Ecology and Evolution, 1996)

Methane consumption by montane soils: implications for positive and negative feedback with climate change - M. S. Torn; John Harte (Biogeochemistry, 1996)

Queen-queen interaction as it related to dominance in polygynous colonies of Myrmica tahoensis - E. Von Wettburg (1996)

Phenotypic plasticity and resource allocation in the leaves of Geranium richardsonii, Mertensia ciliata, and Valeriana occidentalis in a sun dominant versus a shade dominant habit - K. Jakubowski (1996)

Fluctuating asymmetry and reproductive successin Delphinium nelsonii - L. Bone (1996)

A comparison of vegetational maturity and succession rates in an avalanche area - C. R. Whitney (1996)