520 results — topic: Alpine & Subalpine Ecology
The effects of phenological mismatches on demography
Climate change is altering the phenology of species across the world, but what are the consequences of these phenological changes for the demography and population dynamics of species? Time-sensitive relationships, such as migration, breeding and predation, may be disrupted or altered, which may in
Suture-zones of hybrid interaction between recently joined biotas
From a study of the geographic occurrences of contemporary hybridization among North American animals, it has become apparent that most of the hybrids are produced in a few relatively localized zones, with little hybridizing in the vast areas between these zones of mixing.
A meta-analysis of 1,119 manipulative experiments on terrestrial carbon-cycling responses to global change
There is an urgent need to explore the interactions among multiple global change drivers in underrepresented regions such as semi-arid ecosystems, forests in the tropics and subtropics, and Arctic tundra when forecasting future terrestrial carbon-climate feedback.
Complex life cycles and the responses of insects to climate change
Many organisms have complex life cycles with distinct life stages that experience different environmental conditions. How does the complexity of life cycles affect the ecological and evolutionary responses of organisms to climate change? We address this question by exploring several recent case stud
Phenotypic plasticity and adaptive evolution contribute to advancing flowering phenology in response to climate change
Anthropogenic climate change has already altered the timing of major life-history transitions, such as the initiation of reproduction. Both phenotypic plasticity and adaptive evolution can underlie rapid phenological shifts in response to climate change, but their relative contributions are poorly u
Forest responses to increasing aridity and warmth in the southwestern United States
In recent decades, intense droughts, insect outbreaks, and wildfires have led to decreasing tree growth and increasing mortality in many temperate forests. We compared annual tree-ring width data from 1,097 populations in the coterminous United States to climate data and evaluated site-specific tree
The terminology of floral larceny
Scientists’ warning on climate change and insects
Abstract Climate warming is considered to be among the most serious of anthropogenic stresses to the environment, because it not only has direct effects on biodiversity, but it also exacerbates the harmful effects of other human‐mediated threats. The associated consequences are potentially severe, p
Evolutionary options for maximizing pollen dispersal of animal-pollinated plants
On the average, nectar-collecting bumble bees deposited 0.6% of the pollen removed from the flowers of Erythronium grandiflorum (Liliaceae) onto the stigmas of subsequently visited flowers. Because the proportion deposited declined as the amount removed increased, an individual plant would maximize
Evolutionary options for maximizing pollen dispersal of animal-pollinated plants.
On the average, nectar-collecting bumble bees deposited 0.6% of the pollen removed from the flowers of Erythronium grandiflorum (Liliaceae) onto the stigmas of subsequently visited flowers. Because the proportion deposited declined as the amount removed increased, an individual plant would maximize
Competition for hummingbird pollination and sequential flowering in two Colorado wildflowers
The simultaneous flowering of co—occurring plant species with similar pollinator affinities may result in interspecific pollen transfer and consequent fecundity reductions due to wastage of pollen, stigma surfaces, and effective pollinator visits. In such cases competition for pollination occurs and
Temperature response of soil respiration largely unaltered with experimental warming
Significance One of the greatest challenges in projecting future shifts in the global climate is understanding how soil respiration rates will change with warming. Multiple experimental warming studies have explored this response, but no consensus has been reached. Based on a global synthesis of 27
Developing an evolutionary ecology of fear: how life history and natural history traits affect disturbance tolerance in birds
It is suggested that body size and age of first reproduction are important in explaining variation in disturbance tolerance in birds, and that species that capture live prey and those that are highly social are relatively wary.
Pollen dispersal and optimal outcrossing in Delphinium nelsoni
It is suggested that outbreeding depression will often occur on a much finer scale than previously recognised, especially in plants subject to restricted pollen and seed dispersal, and a short outcrossing distance is optimal for Delphinium nelsoni Greene.
A global test of the pollination syndrome hypothesis
The pollination syndrome hypothesis as usually articulated does not successfully describe the diversity of floral phenotypes or predict the pollinators of most plant species. Caution is suggested when using pollination syndromes for organizing floral diversity, or for inferring agents of floral adap
Optimal foraging: movement patterns of bumblebees between inflorescences
Nectar-collecting bumblebees are hypothesized to employ rules of movement which result in the maximum net rate of energy gain (i.e., are optimal), and predicted patterns of movement are compared with field observations to support the hypothesis.
Which is a better predictor of plant traits: temperature or precipitation?
AbstractQuestionAre plant traits more closely correlated with mean annual temperature, or with mean annual precipitation?LocationGlobal.MethodsWe quantified the strength of the relationships between temperature and precipitation and 21 plant traits from 447,961 species‐site combinations worldwide. W
Evolutionary genetics of plant adaptation
The importance of field studies for understanding the evolutionary dynamics of model and nonmodel systems are emphasized, a key life history trait (flowering time) is highlighted and emerging conservation issues are discussed.
Zooplankton competition and predation: an experimental test of the size-efficiency hypothesis
Twelve 42—liter plankton cages were used in an alpine Colorado pond to test a size—efficiency hypothesis: to determine why small herbivorous zooplankton species tend not to coexist with large species. The size—efficiency hypothesis, that large species exclude the smaller ones through competition for
Subalpine meadow flowering phenology responses to climate change: integrating experimental and gradient methods
We integrated experimental and natural gradient field methods to investigate effects of climate change and variability on flowering phenology of 11 subalpine meadow shrub, forb, and graminoid species in Gunnison County, Colorado (USA). At a subalpine meadow site, overhead electric radiant heaters ad
