Researchers estimated the recently discovered modern-looking true crabs are 100 million years old, and they are a part of a complete crustacean fossil ever conserved in a tree amber.
USA Today reported that according to research published recently, the new find rewrites crustacean history, offering evidence that the shrunk crabs, which are half a thumbnail size, may have left their marine shelters briefly to climb a tree during the Crustaceous era.
Originally, amber was found in 2015 by miners in the Southeast Asian jungle after being left untouched for millions of years.
In a press release, Harvard paleontologist and co-author of Javier Luque's study said this is a big moment for crabs. The research, published in Science Advances, was collaborative between Harvard and the China University of Geosciences.
Luque explained that the diversity of form among crabs is fascinating, such an imagination of the scientific and non-scientific public alike, and currently, people are very much looking forward to learning more about such a captivating group "that are not dinosaurs."
The study's co-author also said the fossil has delicate tissues such as antennae, mouthparts lined with fine hairs, big compound eyes, and even gills.
Furthermore, the oldest crustacean was named Cretapsara anthanata, and its finding is meaningful in the examination of crabs as earlier fossils have specified that crabs started crawling out of the water between 50 million and 75 million years ago.
Nevertheless, the cretapsara's discovery means that land-moving crabs could have traveled out of the water as early as 125 million years ago.
Fossils from 75 Million to 50 Million Years Back
If one is to restructure the crabtree of life, Luque said, putting together a "genealogical family tree," some analysis of molecular DNA, the forecast is that non-marine crabs are splitting from their marine ancestors over 125 million years back.
There's a problem, though, due to the actual record of fossils from which the one that can be touched is very young, from 75 to 50 million years old.
Therefore, this new fossil and its mid-Cretaceous age enable researchers to bridge the gap between the forecasted molecular divergence and the crabs' real-fossil record.
The amber, which is 100 million years back or the dinosaur era, bridges the gap between two formerly identified family splits, and, until now, the oldest instance of the so-called "true crab" that ventures onto land and the most intact fossil crab ever found, and it specifies that crabs turned out to be terrestrial or amphibious around that era, much earlier compared to previously believed.
Traditional crabs, also called "true crabs," are differentiated with "false crab" like the king or hermit crabs. Such species are regarded as crustaceans but not crabs as they are in the same family as lobster and shrimp.
'Cretaceous Crab Revolution'
The crab's discovery has resulted in the researchers believing that the type of event identified in the WINK News as the "Cretaceous Crab Revolution," when both true and false crabs are diversifying globally, took place at least 12 separate times.
In addition, Luque explained, it appears like evolution loves to make crabs. Crabs, on the other hand, are doing something quite well, and thus, nature is sorting them out and choosing for those forms instead of their less grumpy relatives.
He continued, describing such excitement at the discovery, crabs generally are fascinating, and some of them are even bizarre-looking.
And presently, people are already excited to learn more about a captivating group that is not dinosaurs. This, Luque concluded, is a big moment for crabs.
Report about the new find is shown on 00Breaking News's YouTube video below:
RELATED ARTICLE: 99-Million-Year-Old Insects Caught in Amber Shows Brilliant Colors
Check out more news and information on Fossils on Science Times.