Graveyard of Giant Extinct Marine Reptiles Might Have Been Birthing Spots for Many Generations, Study Suggests

An international team of researchers has investigated the rich fossil bed at the Berlin-Ichthyosaur State Park in Humboldt-Toiyabe National Forest, Nevada. As per Science Daily, it is known as the graveyard of giant extinct marine reptiles as fossils of ancient animals like the 50-foot-long ichthyosaurs have been found there.

Uncovering its mystery provides a reasonable explanation for how 37 marine reptiles ended up in one location, which paleontologists have been trying to understand for decades. It also provides evidence that generations of ichthyosaurs perished in significant numbers at the site after traveling to the place to give birth.

Uncovering the Mystery Using New and Old Paleontological Techniques

The study, titled "Grouping Behavior in a Triassic Marine Apex Predator" published in the journal Current Biology, shows that ichthyosaurs may have undertaken similar migrations for breeding and giving birth in safer environments about 200 million years before the evolution of giant whales.

SciTech Daily reported that the team examined the rich fossil bed in Berlin-Ichthyosaur State Park (BISP) and presented evidence that these ancient marine reptiles died in large numbers as they migrate to the area to give birth and did so for hundreds of thousands of years.

Nicholas Pyenson, a curator at the Smithsonian National Museum of Natural History said that this means this behavior in whales has been around for 200 million years.

Paleontologists have proposed that ichthyosaurs died in mass stranding events, which is also evident in modern whales, or that they were poisoned by toxins from a nearby harmful algal bloom. However, they lack scientific evidence to support their hypothesis.

So, the team combined new paleontological techniques with traditional means to pore over archival materials, photographs, maps, and field notes to reanalyze them. The site is one of the most well-studied paleontological sites where fossils of marine reptiles were found. Using a 3D model would help in studying the graveyard without losing the ability to go bone to bone.

They also collaborated with other groups to use digital cameras and a spherical laser scanner to take hundreds of photos and millions of point measurements to stitch them together using specialized software. After discovering that environmental conditions did not affect the number of ichthyosaurs on the site, they started looking into the biological reasons.

Finding Embryos and Newborn Fossils in the Graveyard

The bones were preserved in multiple rock levels, suggesting that the species died hundreds of thousands of years apart rather than all at once. The researchers made a significant breakthrough when they discovered several small bones amid the large adult fossils and recognized they belonged to embryos and newborns, CBS News reports.

The researchers determined that the animals, like today's marine giants, went to the spot in groups for safety while giving birth. The fossils are thought to be from mothers and offspring who perished there throughout time.

Moreover, chemical analysis of the dirt revealed that the reptiles were preserved on the ocean floor far from the shore. It implies that the species did not die in mass bleaching events.

The findings offer a plausible explanation for the mystery graveyard. However, the team said that the case may not be fully closed yet although the study helped unlock a little bit more about the mysterious graveyard.