Dataset Information

Bird lineages colonizing urban habitats have diversified at high rates across deep time

ABSTRACT: Abstract

Aim

Urbanization exposes species to novel ecological conditions. Some species thrive in urban areas, whereas many others are excluded from these human‐made environments. Previous analyses suggest that the ability to cope with rapid environmental change is associated with long‐term patterns of diversification, but whether the suite of traits associated with the ability to colonize urban environments is linked to this process remains poorly understood.

Location

World.

Time period

Current.

Major taxa studied

Passerine birds.

Methods

We applied macroevolutionary models to a large dataset of passerine birds to compare the evolutionary history of urban‐tolerant species with that of urban‐avoidant species. Specifically, we examined models of state‐dependent speciation and extinction to assess the macroevolution of urban tolerance as a binary trait, in addition to models of quantitative trait‐dependent diversification based on relative urban abundance. We also ran simulation‐based model assessments to explore potential sources of bias.

Results

We provide evidence that historically, species with traits promoting urban colonization have undergone faster diversification than urban‐avoidant species, indicating that urbanization favours clades with a historical tendency towards rapid speciation or reduced extinction. In addition, we find that past transitions towards states that currently impede urban colonization by passerines have been more frequent than in the opposite direction. Furthermore, we find a portion of urban‐avoidant passerines to be recent and to undergo fast diversification. All highly supported models give this result consistently.

Main conclusions

Urbanization is mainly associated with the loss of lineages that are inherently more vulnerable to extinction over deep time, whereas cities tend to be colonized by less vulnerable lineages, for which urbanization might be neutral or positive in terms of longer‐term diversification. Urban avoidance is associated with high rates of recent diversification for some clades occurring in regions with relatively intact natural ecosystems and low current levels of urbanization.

SUBMITTER: Iglesias‐Carrasco M

PROVIDER: S-EPMC9540638 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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