Ancient megalodon sharks might have been a minimum of 2 metres lengthy at beginning – they usually might need grown so massive by consuming unhatched eggs within the uterus.
Kenshu Shimada at DePaul College in Chicago and his colleagues examined an Otodus megalodon fossil that was recovered within the 1860s from 15-million-year-old rock and is now housed on the Royal Belgian Institute of Pure Sciences. Learning the shark’s vertebrae, allowed them to estimate its physique dimension at varied phases in its life.
“Megalodon’s dimension at beginning was about 2 metres in whole, which signifies that it will need to have given stay beginning like all present-day lamniform sharks do,” says Shimada.
Much like how a tree trunk has annual development rings, the shark vertebrae has development bands. By counting these, Shimada and his workforce counsel that this megalodon specimen died at 46 years outdated.
Earlier research into O. megalodon have relied on proof from its tooth to estimate physique dimension. It’s because teeth are sometimes the one a part of a shark to fossilise, as its skeleton is fabricated from cartilage and never bone. Learning uncommon vertebral stays is important to studying extra about historical sharks, says Jack Cooper at Swansea College, UK.
“The consequence is that only some pups will survive and develop, however every of them can change into massive in physique dimension at beginning which supplies [them] a bonus as already massive predators,” says Shimada.
Whereas the brand new analysis has offered data on the expansion sample between beginning and center age, we nonetheless know little about megalodon development later in life.
Journal reference: Historic Biology, DOI: 10.1080/08912963.2020.1861608
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