Evolutionary and ecological success is decoupled in mammals

Abstract

Aim To identify which factors distinguish ecologically successful mammalian clades (i.e., clades with a large combined range size) from less successful ones. Location Global. Methods We estimated the total range sizes for each individual mammalian subfamily and used phylogenetic regressions to identify the relative importance of factors related to colonization ability (body size and niche width) and adaptability (rate of evolution of body size and rate of evolution of climatic preference) in determining these ranges. We then estimated the importance of the same factors on the variation in diversification rate within mammals. Results We found strong support for a link between total range size and traits related to colonization ability. In particular, we found larger total range sizes among clades containing larger bodied species and clades with wider climatic niche width, while we did not find support for any predictors related to adaptability being linked to total range size. We also found that traits related to increased range size were associated with reduced diversification rate. Main Conclusions Range size for mammalian clades is mainly predicted by colonization ability, suggesting that most clades are limited by dispersal rather than their ability to adapt to new environments. The most ecologically successful (i.e., most widespread) mammalian clades tend to possess traits that reduce geographical isolation among populations, but the same traits tend to decrease diversification rates. Our results unveil a decoupling between evolutionary and ecological success in mammals.

Dispersal ability predicts evolutionary success among mammalian carnivores

“…Despite the difficulties in applying our methodology to other clades, we find it unlikely that the patterns we report here would be taxon-specific. Taxon specificity could have explained why our results appear to run counter to some studies showing lower diversification rates for species with higher dispersal rates (6, 7). We think, however, that the apparent differences are instead a consequence of the taxonomic scale of the analyses and the inclusion or exclusion of fossil taxa.…”

“…The analyses are based on the first species-level phylogeny of carnivores that includes all suitable fossils and all extant species. These results contradict an expected neutral pattern of a trade-off between diversification rate and dispersal, as has been suggested based on analyses of contemporary mammals (6).…”

“…This would explain the apparent conflict between this and earlier analyses of mammals. Earlier analyses at the subfamily level have suggested a negative relationship between dispersal and diversification rate in mammals (6), whereas in a species-level analysis we here recover a positive relationship between the two.…”

Strong but opposing effects of climatic niche breadth and dispersal ability shape bat geographical range sizes across phylogenetic scales

“…These can be broadly classified into extrinsic ones related to historical and biogeographical variables such as species ancestral ranges and time available for range expansion after speciation (Linder, Antonelli, Humphreys, Pirie, & Wüest, 2013;Paul, Morton, Taylor, & Tonsor, 2009), or intrinsic factors linked to species traits, such as diet, environmental tolerances, and their ability to colonize new regions (Slatyer, Hirst, & Sexton, 2013;Slove & Janz, 2011). Despite the evidences linking increased ranges due to the joint action of different processes, two intrinsic traits have been considered of particular importance in explaining interspecific variations in range sizes: species climatic niche breadths and dispersal abilities (Faurby & Antonelli, 2018;Gaston, 2003;Lester, Ruttenberg, Gaines, & Kinlan, 2007;Slatyer et al, 2013;Stevens, 1989).…”

“…Larger ranges generally imply being adapted to a wide array of environments and to having overcome barriers to dispersal, and thus range sizes represent one aspect of species’ success representing the extent of their geographical distributions (Faurby & Antonelli, 2018). Accordingly, addressing range determinants has become essential to understand which processes underlie species distributions at broad geographical scales and how they impact their vulnerabilities to extinction (Böhm et al., 2017; Brown, Stevens, & Kaufman, 1996; Faurby & Antonelli, 2018; Newsome et al., 2020). Several hypotheses have been invoked to explain interspecific variations in species ranges.…”