Longitudinal and cross section of fossils that could turn out to be the first known form of a cephalopod. Credit: Gregor Austermann / Communications Biology
Phys.org has a piece on the discovery of some very old cephalopods. Found in Newfoundland, Canada on the Avalon Peninsula, the animals date to about 522 million years ago during the middle Cambrian. If really a cephalopod, these fossils would push their origin back about 30 million years from what is currently thought. Details can be found in a paper published in Communications Biology.
Possibly the oldest cephalopods in the Earth's history stem from the Avalon Peninsula in Newfoundland (Canada) discovered by scientists from Heidelberg University. The 522-million-year-old fossils could turn out to be the first known form of these highly evolved invertebrate organisms, whose living descendants today include species such as the cuttlefish, octopus and nautilus. The find would indicate that cephalopods evolved about 30 million years earlier than has been assumed.
"If they should actually be cephalopods, we would have to backdate the origin of cephalopods into the early Cambrian period," says Dr. Anne Hildenbrand from the Institute of Earth Sciences. Together with Dr. Gregor Austermann, she headed the research projects carried out in cooperation with the Bavarian Natural History Collections. "That would mean that cephalopods emerged at the very beginning of the evolution of multicellular organisms during the Cambrian explosion."
The chalky shells of the fossils found on the eastern Avalon Peninsula are shaped like a longish cone and are subdivided into individual chambers. These are connected by a tube called the siphuncle. The cephalopods were thus the first organisms able to move actively up and down in the water and thus settle in the open ocean as their habitat. The fossils are distant relatives of the spiral-shaped nautilus, but clearly differ in shape from early finds and the still existing representatives of that class.
