During the Mesozoic Era, it was not merely the dinosaurs that dominated the Earth. The seas around them were home to a wide variety of oceanic reptiles, not closely related to the huge creatures on land. Some of these reptiles used four flippers to cruise through the water while others developed their bodies even further. They are known today as the ichthyosaurs, and history of their discovery and study stretches back far beyond that of dinosaur paleontology. Among the first fossils of extinct beasts from the Age of the Dinosaurs were those of odd ocean creatures, uncovered from the rocks of Lyme Regis in Dorset, England.
These creatures were first brought to light by none other than pioneering fossil hunter Mary Anning, then just a girl, in the year 1811. Soon, more of the ancient animals were found, and curiosity began to spread around both lay and scientific circles. For the longest time, it was thought that the Earth had been created by a divine power, and that the world and its species were just a few thousand years old. The idea of extinction was not familiar to the scientific community of the era. Of course, the presence of an arguably fish-like yet somehow long-jawed and reptilian animal in the cliffs of Dorset began to raise questions. Was it a fish? Was it a crocodile? Perhaps a missing link between salamanders and lizards? Or what about a type of platypus, an animal which had just been found alive? One researcher named Karl Dietrich Eberhard Koenig coined the new name “Ichthyosaurus” in 1817. The name means “fish-lizard”, and was quite evocative although this new title was not scientifically published until eight years later. Much later, in 1835, the order Ichthyosauria was named by Henri Marie Ducrotay de Blainville and both names stuck firmly.
The animals were reptiles, of course. Yet they were reptiles unlike any other alive on Earth. More ichthyosaur remains were discovered all over Europe, and not just from England’s Lyme Regis. It was soon realized that the planet was older than had been presumed, with the first Ichthyosaurus fossils dating back to the Early Jurassic, more than 190 million years old. Both the 18th and 19th centuries were filled with a number of early paleontological innovations and new discoveries, including some unique finds that allowed us to reconstruct not just the bodies but also the lifestyles of the ichthyosaurs.
Fossils in Germany’s Posidonia Shale, also an Early Jurassic site, showed mother ichthyosaurs that died in childbirth. This ichthyosaur, named Stenopterygius, was three meters long, and was also one of the commonest ichthyosaurs found here, with more a hundred specimens known to date. Many of the mothers had died while attempting to give birth to their offspring, succumbing to the pain, shock and blood loss. The portraits of the ancient mothers are still caught in the limestone blocks, and are perfectly preserved to this day. Their young are quite large, although whether or not they cared for their offspring is a matter of debate.
by Julio Lacerda
