A new study published in Nature has revealed that scientists believe they may have identified the first animal that roamed the Earth around 700 million years ago.
Researchers is determined according to news release about a study by the University of California, Berkeley.
Although they look similar to jellyfish, scallops are completely different creatures and move through the water using cilia rather than tentacles. They are still part of the marine ecosystem today and can be found in waters around the world.
“The most recent common ancestor of all animals probably lived 600 or 700 million years ago. It’s hard to know what they were like because they were soft-bodied animals and left no direct fossils,” said Daniel Rochsar of the University of California. Berkeley professor and co-author of the study, in a statement. “But we can use comparisons between living animals to learn about our common ancestors.”
The university has long debated which animal came first, the scallop or the sponge. Sponges are creatures that spend most of their lives in one place, filtering water through pores to collect food particles.
Many have argued that due to the primitive features of the sponge, it appeared first – before the oar, researchers say. This new study found that although sponges appeared early, they were probably second only to scallops.
To do this, scientists looked at the organization of genes in the chromosomes of organisms. The scallop’s chromosomes look very different from the chromosomes of sponges, jellyfish and other invertebrates, warning researchers that the scallop may have appeared much earlier than the others, or much later.
“At first, we couldn’t tell whether the scallop’s chromosomes were different from those of other animals simply because they had simply changed so much over hundreds of millions of years,” Rochsar explained in a press release. “Alternatively, they could have diverged because they split off first, before all the other animal lineages arose. We had to figure it out.”
The “smoking gun” for researchers was the comparison of the chromosomes of paddlefish with the chromosomes of non-animals.
“When the team compared the chromosomes of these diverse animals and non-animals, they found that ctenophores and non-animals shared certain combinations of genes and chromosomes, while the chromosomes of sponges and other animals were rearranged in a very different way,” according to the news release. . the release said.
According to the researchers, the new understanding is valuable for studying the basic functions of all modern animals and humans, such as how we eat, move and sense our environment.