Ichthyosaurs used a barren region of the ocean as an ancient nursery

Michael Marshall is the author.

There is a rich deposit of fossilised marine reptiles found in Nevada. The large creatures seem to have gathered in a quiet area of the ocean.

The discovery shows that breeding behaviors seen in modern marine animals like whales were performed by dinosaurs.

The seas were home to Ichthyosaurs from about 250 million years ago to 90 million years ago.

The Nevada Ichthyosaurs were excavated from the Berlin-Ichthyosaur State Park site in the 70s. Five years after his death from Pancreatic Cancer, his description of the animals was published posthumously, despite the fact that the specimen were ignored for decades.

The species of Ichthyosaurs they are related to is called Shonisaurus popularis. They were between 11 and 15 metres in length and lived 215 million years ago.

Sometimes whales and dolphins strand themselves as a result of a mass stranding event. Neil Kelley says that he imagined that they were left behind when the tide went out.

Smaller animals like fish were not included in the fossils because they could have escaped. The geological evidence shows that the fossils were in deep water.

They re-examined the evidence. They looked for signs of environmental disruptions like volcanic eruptions. He says they couldn't find any evidence of that.

Ichthyosaurs were what they found. The fossils were left in a state of disarray after years of sorting. DePolo had to go through every lump of rock that had been excavated after Camp mentioned that there were embryos. She found the tiny Ichthyosaurs in the final block.

There were at least three juvenile or embryos and a lot of large adult ichthyosaurs found in the reanalysis. The team theorizes that the Ichthyosaurs went to an area of the ocean where there wasn't much to eat to protect their young. There is no evidence that there are other things that can eat babies in this area.

The fossil record is always open to interpretation so we can't be certain. I think it's plausible.

This is in line with other evidence. Ichthyosaurs only gave birth to a small number of young at a time, which suggests that parents care. They may have lived in a group of animals.

There are signs of reptile breeding. The fossils of long-necked plesiosaurs were described in 2006 by Kear and his colleagues. The animals were living in a huge embayment that would have been a sheltered calving ground.

The current biology journal has a reference.

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