DNA and Fossils Place Bats Birthplace in Europe, Study Finds

Overview

Nature reports on a multinational study that merges bat genome data from 103 species with fossil evidence to trace the origins of bats, proposing Europe as the birthplace. The team uses Bat1K genomes anchored to fossils and models continental movement to reconstruct ancestral distributions. Wyoming fossils show flying bats but do not pinpoint where bats first evolved.

• Europe identified as the likely origin of bats through broad genetic and fossil evidence
• Wyoming fossils show flight but do not establish birthplace
• Vielasia skull from France links an early echolocation lineage to the common bat ancestor
• Dispersal analyses suggest subsequent spread to Africa and other continents

Author: Nature

Overview

The article reports on a large international effort within Bat1K that integrates living bat genomes with fossil data to illuminate where bats originated. By analyzing genomes from 103 bat species spanning all 21 living families and assembling anatomical information for 65 species (including 44 extinct ones), researchers move beyond the limitations of studying a few genes. This breadth allows a more nuanced reconstruction of bat evolution that accounts for differences between molecular data and fossil evidence, and it tackles the longstanding question of whether flight or echolocation came first in bat history.

Data and Methods

The new analysis combines high quality genome sequences with fossil anatomy anchored to an evolutionary tree. Researchers anchored their reconstructions to paleogeographic models that consider continental drift and dispersal, enabling ancestral distributions to be inferred in a way that reflects how continents moved over time. The study places particular emphasis on reconciling conflicts that can arise when different DNA regions suggest different relationships among bat groups, and it highlights the value of integrating molecular evidence with fossils to resolve deep-time questions.

In addition to genome-scale data from living bats, the team assembled anatomical information for 65 species, including 44 extinct taxa. This broad dataset strengthens the ability to place extinct species within the bat family tree and to evaluate the sequence of evolutionary events that led to modern bat diversity.

Major Findings

The analysis places the origin of bats in Europe during the late Paleocene, more than 56 million years ago. Descendants then spread into Africa, followed by further movements into other continents as bat groups diversified. The reconstruction identifies strong European support when estimating ancestral distributions and dispersal pathways, painting a picture in which European subtropical forests provided a cradle for early bats before their lineages expanded globally.

An additional important result links echolocation to vielasia, an extinct bat from France. A 50-million-year-old fossil skull described in 2023 shows inner-ear features that indicate sonar abilities similar to those of living echolocating bats. This finding supports the idea that sonar evolved before the major living bat groups diversified, suggesting an ancient origin of echolocation even as the precise sequence of flight and echolocation remains unresolved.

Implications for Bat Evolution

The study integrates genome-scale data with fossil evidence to refine our understanding of how flight and echolocation evolved in bats. It suggests that flight may have preceded or co-evolved with echolocation in some lineages, rather than echolocation arising only after bats became fully flight-capable. The European birthplace scenario also reorients assumptions about how bats dispersed, with later migrations to Africa and beyond shaping current bat diversity. The work underscores the complexity of tracing deep-time origins when modern species can disperse, and when fossils may reflect populations that had already moved far from their origin points.

Biogeography and Future Directions

Parts of late Paleocene Europe offered warm, subtropical forests that could support early bats, and transient land connections through Greenland would have facilitated intercontinental movements. The study does not close all questions about the earliest steps in bat evolution, and the authors acknowledge that fossil sequences documenting the transition from non flying ancestors to earliest flying bats are still sparse. Nevertheless, the breadth and depth of the data mark a milestone for Bat1K and demonstrate the power of combining genomes with fossils to study deep evolutionary history.

Limitations and Open Questions

While Europe emerges as the likely birthplace, the precise order in which flight and echolocation evolved remains unresolved. The oldest known fossils may not represent the first bat ancestors but rather dispersing populations, which complicates interpreting early geographic origins. Future work will aim to fill gaps in European fossil records, expand genomic sampling, and refine models of ancient dispersal to further test and refine the birthplace hypothesis.