Bats originated in Europe, not Asia, landmark genome study reveals

The largest combined study of bat genomes and fossils has traced bats’ origins to Europe and shed new light on how flight and echolocation evolved.

A study involving more than 100 experts worldwide – including only one Australian author, a leading expert in bat evolution from UNSW Sydney – has finally settled decades of debate about the evolutionary origins of one of nature’s most bizarre mammals: bats.

Not only did it pinpoint where bats first appeared – Europe – the work also revealed that echolocation, which allows bats to “see” their surroundings, navigate and hunt using echoes, evolved near the dawn of bat evolution, like flight. The study also lays the groundwork for research into the genetic basis of bats’ exceptional longevity and disease resistance, with potential relevance to human health.

Published today in Nature, the study brought together 137 researchers from 64 countries through the Bat1K consortium, combining genomic and fossil evidence to reconstruct 65 million years of bat evolution.

“Bats have ruled the night skies for about 65 million years, but working out where they first took flight has been more difficult to resolve,” says Professor Suzanne Hand, a palaeontologist with UNSW’s School of Biological, Earth and Environmental Sciences.

“Advances in genome sequencing and computing have now allowed us to compare and combine data from the DNA of living bats with the fossil record in a way that wasn’t previously possible. That has given us a much clearer picture of the early bat family tree – and points to Europe as the place where bats first took flight.”

The findings overturn previous hypotheses proposing Asian, African or North American origins. The earliest bats later dispersed into Africa, establishing a Europe-Africa hub from which they expanded into Asia, the Americas and Australia.

“Even though we now know bats originated in Europe, one of the world’s oldest bat fossil – Australonycteris, which was found in Murgon, South East Queensland – is 55 million years old, so only slightly younger than those in Europe,” Prof. Hand says.

“This record underscores the rapid dispersal of early bats to all corners of the globe once they developed flight.

“Elsewhere in the Oceania region, the oldest bats discovered in the fossil record are otherwise younger, at around 16-18 million years old in New Zealand at St Bathans, Central Otago.”

The team assembled the largest collection of high-quality bat genomes to date, covering 103 species and representing every one of the currently recognised 21 bat families.

“We combined state-of-the-art DNA sequencing and computational methods to generate and compare these genomes and identify the genes they contain,” says Prof. Michael Hiller, Senckenberg Research Institute in Frankfurt, senior author.

The researchers combined the genomic data with 44 fossil bats from across the globe to reconstruct the evolutionary history of the world’s only flying mammals.

‘Evolution’s greatest experiments’

Bats are among the most extraordinary mammals on Earth. They are the only mammals capable of true powered flight. Most bats orient and hunt in complete darkness using sound alone. With more than 1500 species distributed across the globe, bats account for one fifth of all living mammals and play vital roles in maintaining healthy ecosystems by pollinating plants, dispersing seeds and consuming vast numbers of insect pests.

“Bats constantly surprise us. They are one of evolution’s greatest experiments. This extraordinary genomic resource, the culmination of years of international cooperation of Bat1K, is finally allowing us to understand how their remarkable biology evolved,” says Prof. Sonja Vernes, University of St Andrews, Bat1K Co-founding Director and senior author.

Furthermore, many bat species show remarkable resistance to disease and live exceptionally long lives for their size. The genomic resource built for this study gives scientists the first robust evolutionary framework to investigate the genes behind these traits. This work could eventually inform human research into ageing, immunity and disease resistance.

From bumblebee bats to sucker-footed bats

This work represents the largest combined bat genome and fossil study ever undertaken. Building this dataset required samples collected over decades from bats across the world, including representatives of some of the rarest and most unusual bat families, found in the most remote locations.

Among them are the tiny bumblebee bats of Thailand and Myanmar, which weighing in at 2 grams and the length of the last joint on a human thumb, are widely considered the Earth’s smallest mammals. Other weird and wonderful specimens include the remarkable sucker-footed bats of Madagascar, which have suction cups on their wrists and ankles that they use to cling to smooth leaves, and one of New Zealand’s only native mammals, the lesser short-tailed bat, which “walks” along the forest floor using its folded wings as forelegs.

Flight and echolocation evolved early in bats

The fossil evidence also provides important clues about another long-standing mystery: when bats first evolved echolocation.

The placement of the French fossil bat Vielasia – which Prof. Hand analysed in 2023 – within the oldest branch of the bat family tree indicates that echolocation predates the diversification of modern bats. The finding suggests that two of the defining characteristics of bat biology, echolocation and powered flight, were established near the origin of the group itself, helping explain the extraordinary evolutionary success of bats over the subsequent 65 million years.

“Because Australian fossil bats are among the earliest recorded and preserved bats – at 55 million years old – they offer extraordinary insights and empirical evidence into when, where and how flight and echolocation evolved in mammals,” Prof. Hand says.

The team also reconstructed the bat ancestor’s genome, showing what the genetic blueprint of the first mammal capable of flight would have looked like.

“This resource for the community of scientists allows them to investigate the different types of genomic variation, from single base changes to hundreds or thousands of bases missing from one lineage but present in another, that have given rise to the huge variety of bats that we share the planet with, and the origins of their unique characteristics,” says Prof. David Ray, Texas Tech University, senior author.

This gives scientists a genomic map of how one lineage of mammals evolved powered flight, advanced biosonar, exceptional longevity and unusual disease resistance, providing a foundation for research with relevance well beyond bats.

“It is extraordinary, after decades of research and conflicting findings, we finally have a robust phylogenetic tree that we can now use to properly understand how bats’ unique traits evolved. We also have the genomes to uncover the molecular basis of these spectacular adaptations and know where the fossil bats fall in this tree,” says Prof. Emma Teeling, University College Dublin, Co-founding Director of Bat1K and senior author.

Read the paper: https://doi.org/10.1038/s41586-026-11007-3