Evolutionary and ecological success is decoupled in mammals

Area of Science:

• Evolutionary Biology
• Macroecology
• Biogeography

Background:

• Ecological success in mammals is often measured by range size.
• Understanding factors influencing mammalian clade range size is crucial for macroecological and evolutionary studies.

Purpose of the Study:

• To identify traits distinguishing ecologically successful mammalian clades with large range sizes from less successful ones.
• To investigate the roles of colonization ability and adaptability in determining mammalian clade range sizes.
• To examine the relationship between traits influencing range size and mammalian diversification rates.

Main Methods:

• Global-scale analysis of mammalian subfamilies.
• Phylogenetic regressions to assess the importance of body size, niche width, and evolutionary rates.
• Estimation of total range sizes and diversification rates.

Main Results:

• Mammalian clade range size is strongly correlated with colonization ability traits, specifically larger body size and wider climatic niche width.
• Adaptability traits, such as the rate of evolution of body size and climatic preference, were not linked to total range size.
• Traits associated with increased range size were found to be linked with reduced diversification rates.

Conclusions:

• Mammalian clade range size is primarily determined by colonization ability (dispersal) rather than adaptability.
• Traits that facilitate wider geographic distribution may inadvertently decrease diversification rates.
• A decoupling exists between evolutionary success (diversification) and ecological success (range size) in mammals.