Ichthyosaur Brain Reveals Some Of Its Secrets
A modern examination of an exquisitely preserved ichthyosaur unveils enlarged areas of its brain revealing it to be a potentially adept hunter.
Ichthyosaurs may sound like they were dinosaurs but they were in fact marine reptiles, just like their cousins the plesiosaurs and the now famous mosasaurs (from Jurassic World). They had scaly skin and big eyes like most dinos but they were fully adapted for life in water (except for the water breathing part).
Since they resembled dolphins on steroids, ichthyosaurs may not have been the scariest looking of marine reptiles. They were even kinda cute I think. They did however dominate the low warm seas during the Triassic in no small part because they were among the largest apex marine predators ever to have existed. I truly loved the mosasaur in Jurassic World but once you reduce its apparent size of 100 feet to its actual size of around 50, it becomes absolutely comparable to ichthyosaurs in terms of sheer size. But size was only part of the Ichy package. They also had the senses to make them quite skilled hunters. At least that was the theory which has now been reinforced and extended by the first discoveries made about the ichthyosaur brain.
It is very difficult to determine what many marine reptiles had going on inside their craniums. The key reason is that brains are made of soft tissue which does not normally fossilize. The bony brain-case however can offer clues to what was within. Unfortunately, many marine reptiles skulls, especially Incythyosaur’s it seems, have their skulls crushed and flattened from the pressure of the overlying sediment over the years and thousands of millennia.
One specimen however which was found in the 1800s and resides in the Bath Royal Literary and Scientific Institute was preserved with unusual fidelity. It is a 180-million-year-old ichthyosaur named Hauffiopteryx, or Charlie for short. Charlie’s skull was in good enough condition to reconstruct and then fill in the spaces the brain used to occupy, creating an endocast. Using CT (Computerized Tomography) and visualization software, the scientists were able to study key characteristics of the Ichthyosaur brain like no one had done before.
Some had hypothesized that that these marine reptiles had a sophisticated suite of sensing apparatuses and the brain study seemed to bear this out. Charlie’s optic lobes were quite enlarged which would have been a decided benefit to vision during their 600 meter forays deep in the ancient murky seas. The brain’s cerebellum was enlarged as well. This part of the brain deals primarily with motor control making a large one a critical advantage for fine motor control and efficient swimming. The big surprise came when they looked at the olfactory region. This was yet another region that appeared overly large which would make ichthyosaurs adept at smelling their prey perhaps or anything else in their environment that needed smelling.
Overall, Charlie and his kin appear to have had a trifecta of abilities (vision, mobility, and olfaction) that made them the terror of the seas long before mosasaurs came to dominance.
Perhaps the next Jurassic World movie will pit Charlie against a Mosasaur instead of a poor inadequate Indominus Rex.
Main Image: Ryan Marek
Body Image: http://spinops.blogspot.com/2013/12/hauffiopteryx-typicus.html