Fossil study provides evidence of early fruit-eating birds

The early birds were not only able to catch the worm but also to disperse seeds. According to a new scientific study, the earliest-known fruit-eating animal was a bird that lived 120 million years ago, and the existence of such creatures likely contributed to the spread of fruit-bearing plants.

Many birds eat fruits and help plants reproduce by spreading seeds in their droppings, but until now scientists have been unable to find direct evidence of when this animal-plant interaction started.

However, according to researchers from the University of Oxford and the Chinese Academy of Sciences, the answer may lie in a primitive bird species known as Jeholornis, a long-tailed raven-sized creature that lived in China in the Early Cretaceous, around 120 million years ago. The results of the study have been published in the online journal eLife.

As the study points out, some birds eat seeds directly, cracking them open or grinding them up in the stomach to extract the nutrients inside, while other birds swallow seeds whole when they are eating fruit. This second method of eating allows seeds to be dispersed intact in bird droppings, thereby spreading plants through the habitat.

In the study, researchers scanned and reconstructed a fossilized Jeholornis skull and compared it to the skulls of modern birds, finding that the early bird's skull was not built to crack seeds.

They then compared the seed remains found inside Jeholornis fossils with seeds eaten by modern birds, finding that the former showed no signs of grinding. This suggests that Jeholornis ate whole fruits for at least part of the year.

Noting that Jeholornis provides the earliest evidence for fruit consumption in birds, the study said it opens new avenues for scientists to explore how plants and birds might have evolved together. Similar analyses could help unlock new information about how other species interacted with their environments.