Recent analysis of the perfectly preserved fossils of prehistoric crustaceans that lived alongside dinosaurs has allowed us to fill in a crucial gap in the puzzle of the evolution of crabs.
“The Immortal Soul of the Cretaceous Clouds and Waters”
In the context of the work published in the magazine science progressAnd Javier Luc and colleagues fromHarvard university I looked at a 100-million-year-old piece of Chinese amber, which turned out to contain a crab that was likely trapped in resin as it roamed the beach. The analyzes carried out showed that it was a new species fossilbaptized Cretapsara athanata where ” The immortal soul of the Cretaceous clouds and waters ».
Discovery C. two It is exceptional in more ways than one. This tiny, 5-millimeter-long creature has been preserved to be the first dinosaur-age crab preserved in amber (which is extremely rare for aquatic animals) as well as the oldest crab ever identified.
« This is the most complete fossilized cancer ever discovered ‘, destined look. « They include delicate tissues such as antennae, mouthparts lined with fine hairs, large eyes, and even nostrils.. »
Previous lobster fossils (mostly pieces of shells or claws) indicated that crabs had ventured on land and adapted to fresh water about 75 to 50 million years ago. However, to fall into the amber trap, C. two It should develop near a forest consisting of conifers.
A passage from the sea to land much earlier than expected
For the study authors, the crab likely died in a saltwater or freshwater environment near the coast or estuary. This points to the passage of these creatures from the sea to land much earlier than expected (during the time of the dinosaurs, not the time of the mammals) and fills an important gap in understanding their evolution.
« It is sometimes difficult to reconstruct the Tree of Life to track the evolution of the animals we see today, as important pieces of the puzzle are scarce or yet to be discovered. ‘, the researchers estimate. Fossils trapped in amber provide a unique snapshot of the anatomy, biology, and ecology of otherwise inaccessible extinct organisms.. »
In early October, a team of American researchers discovered 16 million-year-old tardigrade fossil in amber.