The Department of Biopsychology at Ruhr-Universität Bochum (RUB) in Germany just issued a press release that aimed to answer what happens in a crocodile’s brain when it hears complex sounds.
The study, headed by Dr. Felix Ströckens, was the first to examine a cold-blooded reptile using magnetic resonance imaging (MRI). According to the press release, “They were thus able to determine that complex stimuli triggered activation patterns in the crocodile’s brain that are similar to those in birds and mammals—a deep insight into evolution.”
While being scanned by the MRI machine, the Nile crocodiles were exposed to both visual and auditory stimuli, and their brain activity was measured. The press release reports, “The results have shown that additional brain areas are activated during exposure to complex stimuli such as classical music—as opposed to exposure to simple sounds.”
Their findings are significant because crocodiles are one of the most ancient vertebrate species and have undergone very few evolutionary changes over the span of 200 million years. This means that these reptiles provide scientists with a link between dinosaurs and bird species. And as stated by the press release, “Consequently, the researchers assume that fundamental neuronal processing mechanisms of sensory stimuli formed at an early evolutionary stage and that they can be traced back to the same origins in all vertebrates.”
To conduct the experiment, there were a series of hurdles they needed to overcome. First, the MRI machine needed to be adjusted to scan a crocodile’s physiology, which took some time. The real concerns came when it was time to actually scan the crocodiles.
According to CNET, the team of scientists could not deeply anesthetize the Nile crocodiles because it would interfere with their brain activity. And they had to be careful, even with the smaller ones, because they can still exert a lot of force with their tails and jaws. Dr. Ströckens told CNET, “Fortunately, they stayed very calm.”
Dr. Ströckens also explained to CNET that “This will allow for future studies to investigate many species which have not been investigated yet with this non-invasive method.”