The lineage that includes octopuses appeared earlier than previously known fossil-based estimates would indicate.
Did dinosaurs appear on Earth before octopuses? This question, which you have no doubt asked yourself all your life, has recently had a new answer. The key is to be found in the dating of fossils.
A brand new study, published in Nature on March 8, 2022, highlights the discovery of a fossil, all the elements of which seem to indicate that it is the most distant known ancestor of the octopus. It is a “vampyropod”, 328 million years old.
This species was named Syllipsimopodi bideni, in honor of US President Joe Biden. This is not a sarcasm to mock the advanced age of the head of state, but a tribute in the eyes of researchers: they made their discovery at the time of his inauguration, where Joe Biden had said ” his general feeling that politicians should listen to scientists “.
At the beginning of the octopuses, the vampyropods
The very first dinosaurs appeared, according to fossil traces, just over 250 million years ago. The oldest known specimen is the Herrerasaurus. They were then some primitive species of dinosaurs. Gradually, the superorder diversified into more species. But of course there were other animals before the dinosaurs — stegocephalians, reptiles… and, in the oceans, probably the first direct ancestors of octopuses.
The fossil recently analyzed in Nature traces the vampyropod lineage back over 300 million years. It has most of the characteristics close to those of an octopus, having for example two rows of suction cups on each tentacle. However, the vampyropods correspond, in evolution, to the beginning of the octopods, the group of marine animals where we find octopuses/octopuses or even the vampire squid. The discovery of this fossil therefore makes it possible to separate the dinosaurs and the octopods from more than 50 million years ago in the history of evolution.
The analysis of this fossil also reveals an astonishing curiosity that is important in the history of these marine animals: it is the only known species of vampyropod with 10 tentacles. Modern octopuses have, as their name suggests, eight functional arms (specifically, octopuses have eight tentacles, while vampire squids have eight tentacles and two small filaments). Naturalists presupposed that at some point in evolution, octopods had “lost” two arms, which this discovery confirms.
