The exoskeleton of the largest arthropod in the world has been found by researchers in the UK.
These enormous most likely lived on Earth between 359 million and 299 million years ago, during the Carboniferous Period. They are car-sized creatures and resembled millipedes.
Scientists already knew about the huge millipede ancestors known as Arthropleura. However the discovery of the new piece of preserved exoskeleton suggests that these prehistoric invertebrates may have been even larger than previously believed. On a beach in Northumberland, northeast England, in 2018, scientists stumbled upon a new fossilized Arthropleura that dates back 326 million years. The fossil was found within a cracked piece of sandstone.
The exoskeleton component has a length of 2.5 feet (75 centimeters) and a breadth of 1.8 feet (55 centimeters). The researchers estimate that the molting individual would have been roughly 8.5 feet (2.6 meters) length and 110 pounds in weight (50 kilograms). According to principal researcher Neil Davies, a geologist at the University of Cambridge in England’s Department of Earth Sciences: ,,They would have been the biggest creatures on land in the Carboniferous.”
Scientists had anticipated that Arthropleura may eventually reach these tremendous heights. They were nevertheless surprised to see any direct evidence of this. According to Davies, the fossil discovery was ,,very fortuitous” because the area where the exoskeleton was found is not known for fossils.
He also commented on how fortunate it was that the fossil could be seen. Davies revealed that the fossil-containing rock had just fallen from the cliff and shattered in the exact spot. The exposed fossil was found by a former Ph.D. candidate who happened to be passing by.
Molted exoskeletons deteriorate quickly, making it difficult for them to fossilize. This one, though, had been extraordinarily well maintained. Davies said, “It seems to have filled with sand soon after it molted. Since it is located in a fossilized river channel, it most likely fell into a small river and was quickly buried by other silt.
Only two other Arthropleura fossils have ever been found, both in Germany, according to Davies. The most recent and largest fossil was discovered. Everything else that scientists know about the enormous invertebrates comes from the fossilized tracks that they left behind in North America and Europe. The size of this new individual was estimated by the researchers. They used data from past fossil and trackway findings. Smaller Arthopleura samples had a breadth to length ratio of 4.78, according to Davies. Therefore, our animal is 2.63 m long since it was exactly 55 cm broad.
Because no head has ever been found, scientists are uncertain of what Arthropleura consumed. However, experts think that these creatures were probably vegetarians who consumed vegetation, trees, and nuts. They could have also eaten other little invertebrates.
Furthermore, it is uncertain how many legs Arthropleura had. The more complete ones thought to have 32 segments, although it’s unclear if they had 64 legs each section or 32 legs per two segments. “The more complete ones are regarded to have 32 segments,” Davies continued.
He remarked that based on this individual’s trackways, it had at least 20 legs. According to Living Science, a new species of live millipede was recently found, however the majority of the current species had less than 100 legs. According to Davies, arthropleura would have been very common towards the equator, which at the time would have been much closer to what is now the United Kingdom. The phenomenon of ,,real polar wander,” which occurs when a planet’s or moon’s outer layer orbits its core and tilts the crust with respect to the object’s axis, causes the equator of Earth to move. The last time this ,,cosmic yo-yo” happened, according to Live Science, was about 84 million years ago.
These invertebrates likely reached such incredible sizes during the Carboniferous period due to the tropical environment in what is now the United Kingdom, as well as a lack of predators and other huge animals. Davies said: ,,It was probably just a big environment that suited them. With little competition from other creatures, they would have had a abundant supply of food from trees and plants.” Arthropleura, however, did not continue in an optimal environment, and about 45 million years after they initially developed, they were extinct.