Madrid, Apr 17 (EFE).- Fragments of amber from the Lower Cretaceous have revealed that beetles fed on dinosaur feathers some 105 million years ago, which shows a mutually beneficial or one-way symbiotic relationship, according to a study published today by PNAS.
An international investigation led by the Higher Council for Scientific Research (CSIC) studied various remains of amber from the deposits of San Just (Teruel), in Peñacerrada I (Álava) and El Soplao (Cantabria).
Thanks to the good preservation that amber allows, it was possible to find larvae of the ancestors of dermestid beetles among the filamentous structures of theropod feathers or down.
This work makes it possible to increase the existing fossil record worldwide, which is scarce, and to delve into a relevant aspect in paleontology.
“Some of the symbiotic relationships of arthropods with vertebrates are well known, for example, those of tick parasitism with various vertebrates,” says Enrique Peñalver, a scientist at the Geological and Mining Institute of Spain (IGME-CSIC) and first author. from work.
The two groups now studied coexisted for more than 500 million years. The main fragments of amber come from the town of San Just (Teruel) and contain beetle larvae moulting between the filamentous structures of the feathers or down.
The molts of these larvae have been related to the current dermestid beetles, a species that currently constitutes a pest that destroys stored products or dry museum collections, since they feed on organic materials that are difficult for other organisms to digest.
Dermestid beetles also play a key role in recycling organic matter in the wild and are commonly found in bird and mammal nests, where feathers, hair, or skin debris accumulates.
It is therefore inferred that the beetle larvae lived −feeding, defecating and molting− in feathers accumulated on or near a resin-producing tree, probably in a nest, adds the IGME-CSIC researcher.
The feathers preserved with the beetle remains belonged to an unknown theropod dinosaur, whether avian (a term that refers to birds in a broad sense) or not, since both types of theropods lived during the Late Cretaceous and shared feather types throughout. often indistinguishable.
The feathers studied did not belong to modern birds, since this group appeared about 30 million years later in the fossil record, during the Late Cretaceous.
The researchers studied three other pieces of amber, each of which contains an isolated beetle moult from a more advanced state of maturation, belonging to the same species, which has allowed a better understanding of the anatomy of these tiny insects, he explains. David Peris of the Botanical Institute of Barcelona.
These specimens were found in two other amber deposits in northern Spain, in Peñacerrada I (Álava) and El Soplao (Cantabria), of approximately the same age as San Just.
“The research shows that the feathered theropod host most likely also benefited from the activity of the beetle larvae that fed on their detached feathers, supposedly in the nests, implying a certain cleaning of the same,” concludes Ricardo Pérez. -de la Fuente, from the Oxford Natural History Museum.