A bat is seen hunting a flying insect in a dark place. (Photo: Getty)

How did bats learn to 'see' in the dark? Landmark discovery explains

Bats may have emerged in Europe about 65 million years ago. Here's what fossils and genetic evidence reveal about their evolution.

by · India Today

In Short

  • Study analysed genomes of 103 bat species and 44 fossils to trace bat evolution
  • Bats evolved powered flight with wings as modified forelimbs, not like birds
  • Research may help understand bats' longevity and disease resistance

How did bats go from mysterious early mammals to the only mammals capable of powered flight?

A landmark study has now traced much of that story back about 65 million years, suggesting that bats first appeared in Europe soon after the mass extinction that wiped out the non-avian dinosaurs.

The study, published in Nature, combines genetic and fossil evidence to reconstruct the most detailed bat family tree yet.

A group of bats is seen hanging from a tree branch. (Photo: Getty)

Researchers analysed high-quality genomes from 103 bat species representing all 21 recognised bat families, alongside 44 bat fossils.

The findings point to Europe as the likely birthplace of bats, overturning earlier assumptions that placed their origins in Asia, Africa or North America.

FROM THE ASHES OF THE DINOSAUR AGE

An asteroid struck Earth about 66 million years ago, triggering a mass extinction that eliminated the non-avian dinosaurs and transmuted ecosystems.

A bat is seen flying under a clear sky. (Photo: Getty)

The study suggests bats appeared in Europe roughly a million years later, before spreading to Africa and eventually across much of the world.

Bats are the only mammals to have evolved powered flight.

What that means is that their wings are not like those of birds, but are modified forelimbs, with greatly elongated fingers supporting a thin skin membrane.

The oldest known bat fossils are about 52 million years old, meaning there is still a gap between the earliest inferred bats and the oldest physical remains.

An image of a bat fossil found in Carlsbad Cavern, US. (Photo: X)

Scientists therefore still do not know exactly what the first bats looked like.

“We don’t know for sure but I reckon they looked like tree shrews starting to grow long fingers. This is just a guess as all of the oldest fossils look like modern bats,” zoology professor Emma Teeling of University College Dublin told news agency Reuters.

HOW DID BATS LEARN TO SEE IN THE DARK?

The study also sheds light on echolocation, which is the ability many bats use to navigate and hunt by producing high-frequency sounds and sensing their echoes.

A bat flies through air in a dark surrounding. (Photo: Getty)

The researchers concluded that echolocation, like flight, evolved near the beginning of bat evolution. But which came first remains unanswered.

“Our oldest bat fossils show that they had both flight and echolocation capabilities, which doesn’t help answer this question," Teeling said. "We need to find the oldest ‘pre-bats,’ or transition fossils, and see if they had anatomical characteristics indicative of flight or echolocation.”

That combination may have opened a new world for bats, allowing them to fly and hunt at night when fewer predators and competitors were active, said Sonja Vernes, a biology professor and one of the study's lead authors.

A close-up image of a bat hanging upside down from a tree branch. (Photo: X)

"Flight got them into the air. Echolocation let them own the night,” Vernes said.

- Ends