Cienciaes.com: The long-tongued amphibian trapped in amber. We spoke with Juan Daza and Arnau Bolet.

2020-11-16 10:28:04

When we look back in time and try to imagine the inhabitants of the Earth 100 million years ago, we inevitably think of dinosaurs. However, those enormous and magnificent animals were not the only ones, our planet was inhabited by an enormous diversity of species of all types and sizes, the vast majority, too small and inconspicuous to take away from the enormous beasts that with them that terrify us in movies like Jurassic Park. Today we are going to break with that tradition with the guidance of our guests in Talking to Scientists, Juan Daza and Arnau Bolet, we present a small creature, barely five centimeters in length in the adult state, that was trapped in the sticky resin of a tree, perhaps a conifer, 99 million years ago.

The current history of this specimen, belonging to a species that has been given the name Yaksha perettii, begins in what are now the extensive amber deposits of the Hukaung Valley in northern Myanmar. Amber is commercially exploited in the area and is usually used to make jewelry and ornaments. Some pieces are not only attractive for their amber color but also because they contain samples of the environment in which they were formed, insects, feathers and other remains of the creatures that inhabited the area in those distant times.

One of the gemologists who deal in Myanmar amber is Adolf Peretti, a person who, throughout his life, has collected an extensive collection of pieces that contain interesting remains of creatures. One day he contacted Juan Daza, a professor of biological sciences at Sam Houston State University, Texas, and proposed to show him his collection of fossil lizards, preserved in amber. The contact was not accidental, Daza had published an article in Science Advances in 2016 in which he disclosed his research on a set of remains of small reptiles from the Cretaceous, which were initially considered to be related to gekkos and chameleons.

Daza convinced Peretti to send his collection to the University of Texas to undergo computed tomography sessions, a non-invasive technique that could obtain digitized images, with a high degree of detail, of the fossil encrustations inside the amber to study its contents.

The conclusions of the 2016 article, signed by Daza and Stanley, raised a series of doubts for Susan Evans, University College London and Arnau Bolet, a researcher at the Institut Català de Paleontologia Miquel Crusafont, some doubts that the collection now provided by Peretti could help to solve. A scientific meeting in Bangkok, held in 2019, allowed Juan Daza, Edward Stanley, Susan Evans, Arnau Bolet and others to discuss the matter and made it possible to create a working group that, subsequently conditioned by the confinement of the pandemic, was able to work at a distance thanks to the tomography images that had been taken from the amber collection. As luck would have it, some pieces, which contained the well-preserved head of an adult animal and the remains of a young specimen, revealed unexpected aspects of these extinct beings.

After careful study of the fossil, the team came to the conclusion that it is not a reptile related to chameleons or lizards, as had been initially believed, but rather an amphibian, that is, the class of invertebrates to which which salamanders or frogs belong. The researchers conclude that it is an animal that belongs to a group of small and enigmatic amphibians called albanerpetóntidos. Identified for having very distinctive characteristics, including the existence of very special scales and joints in the jaw and neck.
The albanerpetóntidos must have been animals that hunted static and took advantage of the proximity of a prey to shoot a ballistic tongue that was projected at great speed and distance from its mouth and capture it.

Currently, the albanerpetóntidos are extinct, although, as the researchers Juan Daza and Arnau Bolet commented during the interview, their existence on earth extended for more than 140 million years and lasted until a couple of million years ago.

We invite you to listen to Juan D. Dazainvestigador del Department of Biological Sciences, Sam Houston State University, en Texas, USAalready Arnau Bolet researcher at the Catalan Institute of Paleontology Miquel Crusafont of the Autonomous University of Barcelona.

References:

Daza et al. Enigmatic amphibians in mid-Cretaceous amber were chameleon-like ballistic feeders. Science. 06 Nov 2020: Vol. 370, Issue 6517, pp. 687-691. DOI: 10.1126/science.abb6005

Daza et al. Mid-Cretaceous amber fossils illuminate the past diversity of tropical lizards. Science Advances 04 Mar 2016: Vol. 2, no. 3, e1501080
DOI: 10.1126/sciadv.1501080