Environmental Variability Shapes Life History of the World's Birds

Area of Science:

• Ecology
• Evolutionary Biology
• Climate Change Biology

Background:

• Life history traits are crucial for organismal persistence in changing environments.
• Environmental variability's influence on life history traits across broad scales remains empirically under-tested.
• Understanding these links is vital for predicting species' responses to climate change.

Purpose of the Study:

• To empirically test how environmental variability influences the pace of life in bird species globally.
• To investigate the differential effects of inter-annual versus intra-annual environmental variability.
• To assess the role of phylogenetic constraints and ecological differences.

Main Methods:

• Synthesized global climate data, species traits, and species range data for 7,477 non-migratory, non-marine bird species.
• Quantified the relationship between environmental variability (temperature and precipitation) and pace of life metrics.
• Accounted for phylogenetic relationships and ecological diversity.

Main Results:

• Species experiencing high inter-annual temperature variability showed a slower pace of life.
• Species experiencing high intra-annual temperature variability exhibited a faster pace of life.
• Precipitation variability had less certain effects; patterns held despite ecological and phylogenetic diversity.

Conclusions:

• Environmental variability, particularly temperature fluctuations, significantly shapes bird species' pace of life.
• Contextualizing environmental change rates against historical variability and species' pace of life is crucial.
• Species facing rapid relative environmental change may be most vulnerable to climate change impacts.