Amber fossils reveal dinosaurs and beetles had symbiotic relationship

Prehistoric beetle larvae encased in frayed feathers and amber reveal a relationship between dinosaurs and insects that dates back more than 105 million years. This is the oldest example of a symbiosis between dinosaurs and arthropods.

Ricardo Pérez de la Fuente, of the Oxford University Museum of Natural History, said: “Finding the wing part was already exciting, but we found the remains of a beetle larvae inside the wing fragment. It was an incredible surprise,” he said.

“Direct evidence of interactions between arthropods and vertebrates is very rare in the fossil record,” says Pérez de la Fuente.

Amber is found in Spain and dates back to the Cretaceous period. The exact species of dinosaur to which the plumage belonged is unknown, but the plumage is consistent with what paleontologists would expect from Velociraptor and ancient bird-like theropod dinosaurs.

At first, Pérez-de la Fuente and his colleagues were unsure whether the link between dinosaur feathers and beetle larvae was more than coincidental. This is because the sap, which hardens to an amber color, envelops any material in its path.

However, upon closer inspection, researchers were able to find evidence that beetle larvae were feeding on the dinosaur’s feathers. According to Pérez de la Fuente, there was also feces made by the larvae between the wings.

According to Perez de la Fuente, there are insects that live by eating birds as parasites, but the story behind Cretaceous dinosaur feathers and larvae is different.

The larvae in amber lack key features that indicate they were dinosaur eaters, the researchers said, including specialized mouthparts for eating skin and blood. Instead, they suggest that the beetle larvae lived and grew in their nests, making the most of what the dinosaurs molted. It is proposed as an example of a mutualism relationship in which both the animal and the dinosaur are both scavengers.

The insect larvae fossils appear to belong to a group of beetles with currently living species. Some present-day species, called skin beetles or skin beetles, have larvae that live in bird nests and consume molted feathers.

“This study provides fairly compelling evidence that Cretaceous longhorn beetles exploited that food source, especially longhorn beetles found in areas where modern nests and shed feathers accumulate. Because they are,” says paleontologist Lisa Buckley.

Ninon Robin of the Royal Belgian Institute of Natural Sciences says the find reveals one of the “oldest dinosaur-arthropod interactions that are very difficult to record in fossils”. .