Researchers often find fossils of ancient creatures, but the brains and soft tissues of these creatures are often missing, making it difficult to accurately understand and describe these creatures.

The Royal Ontario Museum has revealed a collection of fossils containing the brain and nervous system of a nearly half-billion-year-old marine predator. The marine animal, called Stanleycaris, was found in the Burgess Baby Layer, a layer of fossilized sediments found in Canada.

Wonderful treasure

Stanleycaris belongs to the order Actinomycetes; It is one of the extinct evolutionary branches of arthropods, considered distant from modern insects and spiders.

and published Results of this finding – this July 8 in the journal “Current Biology” highlights how the arthropod brain has evolved, including the evolution of vision and head structure.

Researchers discovered this strange animal in an amazing treasure trove of fossils dating back 506 million years. Despite this age, the good state of preservation of these fossils shows that 84 of them still contain good remains of the brain and nerves. Therefore, what intrigued researchers most about this strange animal was within the head “Stanlycaris”.

According to a report published by the website Uric Alert.EurekAlert) commenting on the study, Joseph Moisiuk mentions; The leader of the study at the University of Toronto said, “Although the discovery of fossilized brains from the Cambrian period (the first Paleozoic, which spanned from 541 to 485 million years ago) is not new, the new discovery is well-preserved. These samples were found, in addition to their large number.

Deep details

Thanks to this good state of preservation, scientists can “describe the smallest details related to the visual centers that serve the creature’s large eyes, and because we can clearly see these details, we can also track the nerves that reach the extremities of the creature. It’s like the animal died yesterday,” Moisiuk said.

Today, arthropods, like insects, have brains composed of forebrain, midbrain, and hindbrain. In contrast, the new fossils show that the brain of Stanleycaris was divided into two parts. Forebrain (which connects to the eyes) and Midbrain (which connects to the front claws).

“Thus we conclude that the bipartite head and brain have ancient roots in the lineage of arthropods, whose evolution probably preceded the 3-part brain that characterizes all species belonging to this diverse phylum,” states Moisek.

In addition to terminal eyes, Stanleycaris has a large central eye at the front of the head, which has not previously been observed in radiotooth animals.

Jean-Bernard Caron, curator of invertebrate paleontology at the Royal Ontario Museum and co-author of the study, says, “These animals look even stranger than we thought, because we didn’t expect Stanleycari to have a large third eye. This suggests that early arthropods developed complex visual systems like their contemporary relatives.”

Little hunter

It is noteworthy that during the Cambrian period, rays were one of the largest groups of animals that existed at that time. For example, Anomalocaris – otherwise known as the anomaly shrimp – reached a length of at least one meter.

In contrast, the length of Stanleycaris did not exceed 20 cm, which made it a small animal compared to its group. However, most animals of the time were no more than a finger long. Thus, Stanleycaris may have been an amazing hunter, as the creature’s sensory and visual systems were so sophisticated that it was able to hunt down small prey very efficiently in the dark.

In addition to large compound eyes, “Stanlikaris” had a wonderfully round mouth lined with teeth, and front claws were connected by amazing nerves. The body of “Stanlikaris” was flexible, segmented and had sides to aid in swimming.