Prehistoric Birds Preferred Bugs to Fish, Study Says

Prehistoric dinosaur birds preferred to snack on insects instead of fish, a new study has revealed.

It had been believed that the 120 million-year-old Longipterygidae family's long beaks with sharp teeth at the tip put them in a similar class to modern kingfishers.

Now, new research has shown that the strange avians actually ate insects rather than fish.

Longiteryx feeding on a mayfly
Reconstruction of Longiteryx feeding on a mayfly from the Early Cretaceous Jehol Group of Northeastern China. Miller et al. noted that the foot of Longiteryx could grasp in a way similar to living owls, on which this feeding pose is based. Julius T. Csotonyi/Zenger

Dr. Michael Pittman and his team identified the diet of a group of prehistoric birds in The Chinese University of Hong Kong's (CUHK) School of Life Sciences, in the city of Hong Kong, located in Southern China.

The study was published May 12 in the international journal of biology BMC Biology.

Pittman and his team investigated previous assumptions made about these birds' diet based on quantitative fossil evidence.

The team investigated more than 150 living bird species, combining four separate lines of evidence – body mass, claw shape, skull bite efficiency, and skull bite strength – to reconstruct the diet of the ancient birds.

The team found that rather than eating fish, the birds were most likely to feed on invertebrates like insects, or to eat a variety of foods.

The study focused on the feeding habits of the Longipteryx, a member of the wider Longipterygidae family.

Case Vincent, the first author of the research and Pittman's Ph.D. student, said: "Longipteryx birds have a smaller body mass and in particular weaker jaws than most living fish-eating birds like kingfishers.

"The evidence pointing to Longipteryx not being a specialist fish-eater surprised me the most, as it was previously assumed that was why they evolved such long jaws."

Reconstructions of longiterygid skulls
Reconstructions of longiterygid skulls used in the study. Colors indicate which individual fossils the parts were taken from, as no complete skulls are known. Two reconstructions are made for Longiteryx as two distinct skull shapes were noticed by the authors. Case Vincent Miller/Zenger

This means birds in the longipterygid family were evolving their long snouts while keeping the same diet as their ancestors, which suggests their unique skulls evolved for a reason other than a change in diet.

The study hypothesizes that the strange jaws of longipterygids may have helped in removing parasites, cooling down their body, or enhancing their senses in some way.

Pittman said: "There is still a lot of work to do, which includes adding additional methodologies to narrow dietary habits further, to form a more complete record of bird ecology."

Pittman added: "Birds eat just about everything today, but the origin of such a range of diets is a mystery.

"Understanding the diet of extinct birds is key to understanding their ecology, and in turn prehistoric ecology as a whole."

Kingfisher on branch over Wandle in England
A kingfisher sits on a branch over the river Wandle in Wandsworth on August 26, 2020, in London, England. Dan Kitwood/Getty Images

This story was provided to Newsweek by Zenger News.