Scientists at the University of Cambridge have discovered a fossil like the earliest starfish, which helps us understand the origin of the obese creature.
The prototype Starfish, which has features in common with both sea lilies and modern starfish, is a missing link for scientists trying to unify its early evolutionary history.
Exclusively preserved fossil, named Cantabrigiaster fezouataensis:, found in the Antarctic Range of Morocco. Its intricate design, with its lace-like feather arms, was once frozen for about 480 million years.
The new species is unusual because it lacks many of the basic characteristics of its modern relatives – lacking about 60% of the modern starfish’s body plan.
The properties of copper are instead a hybrid between a starfish, a sea lily or a crinoid. Not a plant, but a feeder with a corrugated filter, which attaches itself to the sea with a cylindrical “stem”.
The discovery, reports Biology letters, captures the early evolutionary stages of the animal at a time in Earth history when life suddenly expanded, a period known as the Ordovician Biodiversity Event.
The discovery also means that scientists can now use the new find as a prototype to find out how it evolved from this more basic egg to the complexity of their contemporaries.
“Finding this missing link from their ancestors is incredibly exciting. “If you had come back in time and put your head under the sea in Ordovician, you would not have known any marine organisms, except the starfish, they are one of the first modern animals,” said lead author Dr. Aaron Hunter, visiting the Department of Earth Sciences.
Modern-day starfish and brittle stars are part of a family of prickly-skinned animals called echinoderms, which, although not vertebrate, are the closest group of vertebrates. Crinoids և Otherworldly creatures such as sea urchins and sea cucumbers are all echinoderms.
The origin of the star Ovast has been avoided by scientists for decades. But the new species is so well preserved that its body can finally be mapped in detail to understand its evolution. “The level of detail of the sample is amazing. Its structure is so complex that it took us a while to figure out its potential, ”Hunter said.
Hunter’s work on both living and fossil echinoderms helped him discover its hybrid properties. “Looking at a modern crinoid in one of the collections of the Museum of Western Australia, I realized that the hands really look familiar. “They reminded me of this unusual fossil that I found years ago in Morocco, but which was difficult for me to work with.”
Moroccan Fezuata is a sacred lamb for archaeologists. The new fossil is simply one of the few places that has been found on the site of many surprisingly well-preserved soft-bodied animals.
The hunter, co-authored by Dr. Javier Ortega-Hernandez, formerly of the Cambridge Department of Zoology now at Harvard University, named the species Cantabrigist in honor of the long history of echinoderm research in their respective institutions.
Hunter and Ortega-Hernandez explored their new species alongside a catalog of hundreds of starfish-like animals. They indexed all the structures and features of their body by building an echinoderm skeleton roadmap that they could use to assess how Cantabrigist was related to other family members.
Modern echinoderms have many shapes and sizes, so it will be difficult to figure out how they relate to each other. New analysis that uses external theory. The model of biology, which was usually applied only to living species, meant that Hunter և Ortega-Hernandez could find out the similarities and differences between the body plan of modern echinoderms and then find out how each member of the family related to their Cambrian ancestors.
They found that only the key or key part of the body, the food groove that nourishes food along each starfish’s, is present. CantabrigistLater, everything was added, except for the external key parts of the body.
The authors plan to expand their work in search of early echinoderms. “In the future, we hope to answer something about why the starfish developed their five arms,” said Hunter. “It simply came to our notice then. We do not know why. We still have to keep looking for the fossil that gives us that special connection, but going back to our early ancestors as Cantabrigist We are approaching that answer. “
Reference. Aaron V. Hunter և Javier Ortega-Hernandez, 2021 January 20 “New Somastoid from Morocco Fezuata Lagerstote կ Early Ordovician origin of Asterozoa”. Biology letters,
DOI: 10.1098 / rsbl.2020.0809: