Scientists say they’ve unearthed Australia’s oldest recognized crocodile eggshells, a discovery that might shed light on historical reptiles that could have hunted prey by dropping on them from trees.
The eggshells belonged to mekosuchine crocodiles, a prehistoric creature that dominated Australian waters 55 million years in the past — a very long time earlier than the arrival of saltwater and freshwater crocs on the continent round 3.8 million years in the past.
Paleontologist Michael Archer stated mekosuchine crocodiles might develop to at the very least 5 meters (round 16 ft) lengthy, and a few hunted from trees. Australian researchers have dubbed them “drop crocs,” a reference to the scary “drop bear” — the vicious, carnivorous cousin of the nation’s beloved koalas, or so the legend goes.
“It’s a bizarre idea. But some of them appear to have been terrestrial hunters in the forests,” stated Archer, a professor on the University of New South Wales in Sydney who took half within the examine.
“They were perhaps hunting like leopards — dropping out of trees on any unsuspecting thing they fancied for dinner,” he stated in a press release.
A group of worldwide scientists, led by Institut Català de Paleontologia Miquel Crusafont in Barcelona, dug up the fossils from a rancher’s yard in southeast Queensland and studied them. They reported their findings Tuesday within the Journal of Vertebrate Paleontology.
The historical crocodile eggshells are serving to scientists to know the anatomy of those reptiles, in addition to their replica patterns and flexibility, the examine’s lead writer, Xavier Panadès i Blas, stated.
“They preserve microstructural and geochemical signals that tell us not only what kinds of animals laid them, but also where they nested and how they bred,” he stated within the assertion.
Mekosuchine crocs are believed to have develop into extinct in Australia round 3,000 years in the past. They could have misplaced a lot of their inland habitat on account of encroaching dryland, a scenario compounded by rising competitors with different predators and the dwindling quantity of prey, stated co-author Michael Stein, a analysis affiliate on the University of New South Wales.
The precise location of the invention is a small city referred to as Murgon, about three and a half hours’ drive from Brisbane, the capital of Queensland.
Archer stated he and his colleagues had been excavating there since 1983, and he might nonetheless recall the way it all started.
“UNSW colleague Henk Godhelp and I drove to Murgon, parked the car on the side of the road, grabbed our shovels, knocked on the door and asked if we could dig up their backyard,” he stated.
The residents “grinned and said ‘of course’” after listening to their properties have been sitting on some prehistoric treasures, Archer recalled.
“And, quite clearly, from the many fascinating animals that we’ve already found in this deposit since 1983, we know that with more digging there will be a lot more surprises to come,” he stated.
It’s inherently troublesome to determine an extinct species primarily based on an eggshell, stated Dean Lomax, a paleontologist and writer of “The Secret Lives of Dinosaurs — Unearthing the Real Behaviors of Prehistoric Animals.” He wasn’t concerned within the new analysis.
However, given that the eggshell was present in the identical geological deposits and locality of the one recognized mekosuchine fossils from that time frame, Lomax stated the authors made a stable argument.
“I think one of the key things here is that matching the fossil egg shells and the croc that laid them can provide new information,” he stated. “It will help us to understand not only how they reproduced and where they laid their eggs, but the connection may help shed light on the lifestyle of these unusual crocs.”