Reconstructing the geographic and climatic origins of long‐distance bird migrations

Abstract

Aim Seasonal bird migration is one of the most fascinating global ecological phenomena. Yet, the biogeographic scenarios and climatic drivers that led single species or entire lineages to evolve seasonal migration between disjunct breeding and wintering ranges remain unclear. Based on distribution and phylogenetic data for all birds worldwide, we explored the biogeographic and climatic context of the evolutionary emergence of seasonal geographic migration in birds. Location Global. Taxon The Aves class (9,819 species). Methods We used the worldwide phylogeny of all birds, with a new backbone tree, to test the link between birds’ migration distance (short, variable, long) and strategy (resident, mixed, strict migrant) with four different metrics depicting species’ thermal niches in their breeding and wintering ranges. We also performed ancestral state reconstructions for the main migratory orders to reconstruct past events of appearance and loss of migration behaviour, and past biogeographic scenarios that led to the emergence of seasonal geographic migration. Results Migratory species generally experience warmer climates in their wintering range compared to their breeding one, although notable exceptions exist. This thermal niche change due to migration was found to be much larger for species travelling large distances. We also found that geographic migration emerged at different time periods through varied biogeographic paths (i.e. both from temperate and tropical ancestors) and that migration behaviour was likely ancestral to Passeriformes, with several subsequent episodes of loss of migration behaviour. Main conclusions We report an evolutionary correlation between long‐distance migration and the tendency of birds to seek warmer climates during their non‐breeding period, compared to short‐distance migrants. Migration behaviour was likely ancestral to Passeriformes, and migratory lineages in general seem to have often adapted to novel ecological opportunities by returning to a resident state. Our results provide the first large‐scale study of biogeographic and climatic origins of bird migration worldwide.

Biologia Futura: rapid diversification and behavioural adaptation of birds in response to Oligocene–Miocene climatic conditions

“…3 (continued) 2013) and in Turdus (Nagy et al 2019). This pattern is congruent with the findings of a study that examined a broader set of taxa, in which migratory lineages appeared earlier during the evolution of the Passeriformes (Dufour et al 2020). Similarly to raptors, speciation and rapid radiation also started in Turdidae during the Miocene (Nagy et al 2019;Nagy 2019).…”

“…boreal, mountainous, arid, tropical) migration is more likely to have evolved early (e.g. Dufour et al 2020). Consequently, the ancestral migratory behaviour established the flexibility for other behavioural changes such as in foraging strategies.…”

“…This again supports the idea that the global cooling during the Oligocene as well as the extension of grassy vegetation during the Miocene facilitated diversification and behavioural changes throughout the entire radiation of birds. Migration probably evolved because it provided advantages for passerine birds during periods of rapid changes in climate (Dufour et al 2020) and it was more likely an ancient behaviour in this species-rich group of birds.…”

Search for top-down and bottom-up drivers of latitudinal trends in insect herbivory in oak trees in Europe

“…Several factors may explain the lack of response of avian predation to latitudinal or climatic gradients. First, bird species are distributed through migration allowing them to breed at higher latitudes, resulting in a constant predation rate across climatic and geographical clines (Dufour et al, 2020). In contrast, other predators with lower mobility such as arthropods (e.g.…”

A tale of two seasons: The link between seasonal migration and climatic niches in passerine birds

“…For example, Zurell et al (2018) found that migratory birds track green vegetation (measured by NDVI) to a greater degree than climatic conditions. In contrast, Dufour et al (2020) found no evidence of niche tracking when examining the temperature niche.…”