04/10/2026
🕵️♀️🦇 New research has rewritten the evolutionary history of bats, providing evidence the winged mammals most likely originated in Europe during the late Palaeocene, some 65-60 million years ago.
Scientists have long struggled to establish where bats first originated, with previous hypotheses proposing Africa, Asia and North America.
By combining genomic data from all living bat families with ancient fossil records, an international team of 137 researchers from 64 countries working as part of the Bat1K consortium, a global initiative dedicated to sequencing the genomes of all living bat species co-founded by UCD’s Professor Emma Teeling, have reconstructed the evolutionary history of the world's only mammals capable of true powered flight.
The landmark study published in Nature analysed 103 bat genomes, including 42 newly generated chromosome-level assemblies, representing all 21 recognised bat families. This was combined with evidence from 44 fossil bats.
The results provide a clearer picture of where and how this remarkable lineage emerged.
The researchers found that bats most likely first evolved in Europe during the late Palaeocene. And from there, their descendants spread into Africa.
As bats diversified, different groups then expanded independently into the Americas, Asia and Australia, eventually giving rise to the major bat groups found around the world today.
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, and they account for one fifth of all living mammals, playing a vital role in maintaining healthy ecosystems across the globe.
Many bat species show remarkable resistance to disease and live exceptionally long lives for their size. Yet despite their unique biology and ecological importance, scientists have struggled for decades to answer some of the most fundamental questions about their evolution.
“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 and where bats’ unique traits evolved,” said leading senior author and co-founding Director of Bat1K Professor Emma Teeling, UCD School of Biology and Environmental Science.
“We also have the genomes to uncover the molecular basis of these spectacular mammalian adaptations and know where the fossil bats fall in this tree.”
Contributing to the project as part of the international Bat1K consortium were Assistant Professors Graham Hughes and Zixia Huang, both from UCD School of Biology and Environmental Science.
The new research findings shed light on how bats developed two of their defining characteristics, powered flight and echolocation.
“As bats are the only mammals known to have evolved true powered flight, our findings point to Europe as the most likely place where mammalian powered flight first evolved,” added Professor Teeling.
Meanwhile, analysis of the fossil bat Vielasia, which sits on the oldest branch of the bat family tree, indicates that echolocation had already evolved near the beginning of bat evolution.
Together, the findings suggest that powered flight and echolocation predate the diversification of modern bats, which might help explain their extraordinary evolutionary success.
“The approach we used to model the evolution of fossil and living species together can do what other methods cannot - identify the oldest group of fossil bats while taking the genomic data into account, and uncover when and where bats originated,” said senior author Professor Liliana M. Dávalos, Stony Brook University.
Computationally reconstructing the genome of the ancient ancestor from which all living bats descended, researchers are able to offer a glimpse into the genetic make-up of one of the earliest flying mammals.
This new genomic resource will allow scientists to investigate the genetic changes behind bats' extraordinary diversity and adaptations, including flight, echolocation, longevity, and disease resistance.
“We combined state-of-the-art DNA sequencing and computational methods to generate and compare these genomes and identify the genes they contain,” said senior author Professor Michael Hiller, Senckenberg Research Institute, Frankfurt.
The genomic resource built for this study could eventually inform human research into ageing, immunity and disease resistance.
“Bats constantly surprise us. They are one of evolution’s greatest experiments,” said senior author Professor Sonja Vernes, University of St Andrews, and Bat1K co-founding Director.
“This extraordinary genomic resource, the culmination of years of international cooperation of Bat1K, is finally allowing us to understand how their remarkable biology evolved.”
“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,” added senior author Professor David Ray, Texas Tech University.
This new study represents the largest combined bat genome and fossil study ever undertaken, drawing on samples collected over decades from bats around the world, including some of the rarest and most unusual species found only in the most remote locations.
Alongside establishing a likely evolutionary origin for bats, it also resolves several long-running debates about relationships between bat families, revealing unexpected connections between some of the world's most unusual bats.
“This dataset represents decades of work by field researchers from around the world, collecting samples from some of the most remote places, from New Zealand to Madagascar,” said Professor Teeling.
"None of this would have been possible without the dedication and collaboration of these researchers, working together through the Bat1K consortium to bring these samples together, allowing us to tell the evolutionary history of these extraordinary flying mammals."
Remapping these relationships was particularly challenging because different parts of bat genomes can tell different stories about their evolutionary history due to the likelihood that different bat lineages exchanged genes early in their evolution.
This means that while some parts of the genome suggest one set of relationships, others point to another.
However, researchers found that a region of the X chromosome retained a particularly clear signal of the underlying relationships between bat groups, allowing them to resolve decades of conflicting evolutionary trees.
The European Research Council, Science Foundation Ireland, and the Irish Research Council supported the study in part, alongside international partners.
