A new study that brings together genomic data from living bats and evidence from ancient fossils suggests bats may have first appeared in Europe 65 million years ago. That finding redraws what scientists know about the origins of bats and their rise into one of the most successful mammal groups on Earth.
A group of 137 scientists from 64 nations have mapped the evolutionary journey of bats using 103 genomes, with 42 newly produced chromosome-level assemblies included among them, spanning every one of the 21 recognized bat families. The research drew on evidence from 44 fossil bats as well. The project was conducted via the Bat1K consortium, a worldwide initiative aimed at sequencing the genomes of all living bat species, which was co-established by UCD Professor Emma Teeling.
A paper in Nature indicates that bats originated in Europe during the late Paleocene, about 65 to 60 million years ago. Their progeny subsequently spread into Africa, where they split into distinct branches that later pushed into the Americas, Asia, and Australia. These movements eventually gave rise to the principal bat families seen across the globe today.
Europe as Birthplace
Researchers have long argued over the original home of bats. Africa, Asia, and North America have all been suggested as potential origins. But genomic and fossil evidence now suggests Europe is the most probable birthplace for these animals.
“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,” said Professor Teeling, the lead senior author and co-founding Director of Bat1K at UCD School of Biology and Environmental Science.
The results shed light on how two key bat traits came into being: the ability to fly with power and the use of sound for navigation. Scientists studied the fossil of Vielasia, a bat from the very first branch of the bat family tree, and found that the use of sound for navigation seems to have been present near the start of bat evolution.
When combined, the evidence suggests that powered flight and echolocation appeared before modern bat groups started diversifying. These capabilities likely contributed to the evolutionary success of bats.
A Tree Built From Genomes and Fossils
This research draws its power from merging genomic data with fossil evidence. The 103 genomes feature 42 newly created chromosome-level assemblies, spanning every one of the 21 recognized bat families. The team also drew on evidence from 44 fossil bats.
Researchers say their method reveals a clearer picture of how bats emerged and spread around the planet. They describe it as an approach that can identify the oldest group of fossil bats while factoring in genomic data, and uncover when and where bats first appeared.
Professor Liliana M. Dávalos of Stony Brook University was the senior author on the study, according to “This 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,”.
Flight and Echolocation Appeared Early
Among the most unusual mammals on Earth are bats, which are the only mammals able to fly with true power over a sustained period. Most species also navigate and hunt in darkness by means of sound. Bats make up roughly one fifth of all living mammal species, and they carry out significant roles across the globe.
Decades of research have failed to fully explain how bats evolved or how they developed the unusual traits that allow many bat species to resist disease and live far longer than other mammals of similar size.
“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 Professor Teeling.
“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.”
Graham Hughes and Zixia Huang, Assistant Professors at UCD School of Biology and Environmental Science, were part of the project via the international Bat1K consortium.
Reconstructing an Ancient Genome
A computational reconstruction of the genome belonging to the ancient ancestor of all living bats has been created. It provides insight into the genetic makeup of one of the first flying mammals, and it builds a new resource for studying how bats came to develop their remarkable variety.
The dataset gives scientists a tool to study the genetic changes linked to flight, echolocation, longevity, and disease resistance. It could also shed light on why many bats show an unusual level of disease resistance and live far longer than their size would suggest.
Professor Michael Hiller of the Senckenberg Research Institute in Frankfurt is the senior author of the study, according to “We combined state-of-the-art DNA sequencing and computational methods to generate and compare these genomes and identify the genes they contain,”.
This collection of genomic data might eventually aid human studies into ageing, immunity, and how well the body holds up against disease.
Professor Sonja Vernes, who is a senior author on the study and the Bat1K co-founding Director, said “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.”
The Scale of the Study
The scale of the study is itself notable. 137 researchers from 64 countries worked together on this single project. That kind of collaboration is increasingly common in genomics, but this particular effort spans continents and decades of research.
The study’s conclusions rest on two main findings:
- Bats first evolved in Europe during the late Paleocene, roughly 65 to 60 million years ago.
- Flight and echolocation emerged near the beginning of bat evolution.
| Finding | Evidence |
|---|---|
| Origin in Europe | Most likely place |
| Flight origin | Europe |
| Echolocation origin | Vielasia fossil |
Living bats from every one of the 21 recognized families provide the genomic data, alongside 44 fossil specimens, which together show a group that began with just a few species in Europe and then spread worldwide over tens of millions of years.
Why This Matters
This study’s genomic resource has the potential to illuminate human biology, because bats share certain traits with us — longevity and disease resistance — that researchers would like to understand better.
A substantial amount of material underpins the research’s findings. Both the genetic information and the historical record of remains back up the sequence of events.
This study offers a strong foundation for resolving fundamental questions about bat evolution, which the researchers have worked on for decades. They recognize the significance of their own work.
This study has opened up new paths for further investigation. By reconstructing the genome of an ancestral flying mammal, researchers have gained insight into the genetic makeup of these early animals. The genomic material produced through this work could prove useful in human research focused on ageing, immunity, and disease resistance.
A collaboration that spans 64 countries and brings together 137 researchers stands as a notable achievement on its own. It speaks to how science now operates across borders.
This study demonstrates how far science has come in grasping bats, one of evolution’s most remarkable experiments.
Source material: “Bats may have first evolved in Europe 65 million years ago,” ScienceDaily.
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