Summary
A genome-scale analysis combining bat DNA with fossil anatomy identifies Europe as the probable origin of bats, and therefore powered flight, in the late Palaeocene. The study also revises relationships among bat families and places laryngeal echolocation before the diversification of living bats.
A study combining chromosome-level genomes from 103 bat species with fossil anatomy points to Europe as the probable origin of bats in the late Palaeocene. Because bats are the only mammals capable of powered flight, the researchers’ reconstruction also places the origin of powered flight in Europe. The findings, published in Nature, revise both the bat family tree and estimates of where its earliest branches arose.
How the study rebuilt bat history
The researchers analysed long-read genome assemblies representing all 21 currently recognized bat families. The dataset included 42 new assemblies, alongside existing genomes, and eight non-bat mammal species used as outgroups to help establish relationships. They compared several types of genomic evidence, including neutrally evolving DNA, and used multiple methods to infer the evolutionary tree.
To bring fossil species into the analysis, the team assembled a morphological dataset of 699 characters across 65 species. It included 44 pre-Quaternary fossils and representatives of most living bat families. The researchers combined these anatomical data with genomic evidence and used fossilized birth–death and dispersal–extinction cladogenesis analyses to estimate the timing and geographic history of bat evolution.
That combined approach matters because the oldest known bat fossils date to the early Eocene, about 56–52 million years ago, and have been found in several regions. Those fossils show that flight and echolocation had evolved by then, but the fragmented record has made it difficult to identify where bats first arose. Integrating fossil placements with a broad genomic tree gives the researchers a way to test geographic origins that the fossils alone have not resolved.
A revised family tree and an earlier echolocation history
The analysis supports a European origin for bats in the late Palaeocene. The authors describe this as probable: it is a reconstruction based on the combined fossil, genomic and biogeographic analyses. Earlier studies had proposed African, North American or Asian origins, in part because of limited genomic sampling and gaps in the fossil record.
The new tree also revises relationships among bat groups. It places Myzopodidae as the earliest branch within Vespertilionoidea and identifies Emballonuroidea and Vespertilionoidea as sister groups. The analyses support the two major bat suborders, Yinpterochiroptera and Yangochiroptera, rather than grouping all echolocating bats together as the former category Microchiroptera.
The placement of the fossil †Vielasia in the oldest ‘Eochiroptera’ clade suggests that laryngeal echolocation evolved before the diversification of crown bats—the group comprising living bats and their descendants. The result adds to evidence that key bat traits arose early, while the revised tree offers a framework for studying how their distinctive biology evolved.