BEACON TRANSCRIPT – A new discovery made by Canadian scientists offers a fresh perspective on the evolution of mandibulates. They found an incredibly well preserved fossil of a sea creature which lived 507 million years ago. The creature belongs to the arthropod group, which also encompasses the mandibulate subcategory.
Mandibulates belong to the same large group which includes insects, ants, crabs, flies, and centipedes. The name comes from the fact that they have mandibles, which represent some extremities they use to grab and crush food. Now, this discovery might help scientists find out more about their evolution.
The fossil was a large marine predator
The fossil was hiding in some sedimentary rocks found in the Marble Canyon, situated in the Kootenay National Park in British Columbia. The researchers from the University of Toronto and paleontologists from the Royal Ontario Museum decided to call the creature Tokummia katalepsis.
They included the creature among arthropods, one of the largest groups of invertebrates. They can be identified after their hard exoskeleton, so mandibulates represent one the subgroups which belongs to this category.
T. katalepsis lived during the Cambrian period, and it represented one of the largest sea predators to swim in tropical waters. The creature could extend and reach 4 inches, and it usually chose to stick to the bottom of the ocean rather than swim closer to the surface. Besides the mandibles, they also had pincers, which are also widely found in mandibulates.
The creature provides information on the evolution of mandibulates
Researchers explained why they chose to live on the muddy bottom of the sea. They suggest that they might have not been able to kill animals hiding in shells, so they chose to hide on the bottom and hunt softer creatures. They used the pincers to kill the animals and then the mandibles to cut them into pieces.
Also, T. katalepsis’ body is segmented in around 50 pieces and is covered in a shelly structure called carapace. Their limbs have some small projections which researchers think have evolved into legs in today’s mandibulates. Also, the lack of an antenna makes the shift from crustacean to terrestrial creatures.
The name of the animal comes from the area where the researchers found the fossils, Tokumm Creek, and the Greek for ‘seize’. All the findings were published in a study and it can be found here.
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