The First Flying Mammal May Have Taken Off in Europe, Not Asia

Keypoints:

• A landmark Bat1K study combined 103 bat genomes with 44 fossils, the largest such analysis ever conducted
• 137 researchers from 64 countries traced bat origins to Europe, roughly 65 to 60 million years ago
• The finding overturns decades of assumptions pointing to Asian, African, or North American origins
• Echolocation and powered flight appear to have evolved together, near the very start of bat evolution
• Findings were published September 23 in Nature

For decades, researchers debated where bats first appeared, with most theories pointing toward Asia, Africa, or North America. A landmark study just overturned that assumption entirely, tracing the origin of the only mammals capable of true powered flight back to Europe, roughly 65 to 60 million years ago, right in the aftermath of the asteroid impact that wiped out the dinosaurs.

The scale behind the finding is what makes it credible. Working as part of the international Bat1K consortium, 137 researchers across 64 countries combined genomic data from 103 bat species, representing all 21 recognized bat families, with 44 fossil specimens in the largest combined bat genome and fossil study ever conducted. 

Lusíola Dávalos of Stony Brook University, one of the study's authors, explained the method's real advantage: modeling fossil and living species together, rather than separately, let the team place the oldest fossil bats within the family tree while accounting for genomic data at the same time, pinning down both when and where the group actually arose.

The study also settled a second long-running question. Echolocation, the biological sonar bats use to navigate in the dark and hunt flying prey, appears to have evolved alongside flight itself, near the very root of the bat family tree, strengthening the case for a single, ancient origin rather than the trait evolving separately multiple times. 

Professor Emma Teeling, a co-author on the project, called the resulting genomic resource "the culmination of years of international cooperation," one that's now letting scientists investigate the specific genes behind the traits that made bats one of evolution's biggest success stories.