Seabed worm shares 70% of human genes
Published 18/11/2015 | 18:21
Say hello to your long-lost relative - this fleshy pink worm living on the seabed is a distant cousin of humans and shares about 70% of our genes.
Scientists believe our wormy ancestry can be traced back to the Cambrian explosion, a surge in evolutionary diversity that occurred about 550 million years ago.
Acorn worms live on the ocean floor and feed by filtering sea water through slits that are distantly related to the gills of fish.
Genetic analysis of two acorn worm species from Hawaii compared their DNA with that of 32 diverse animal species including humans.
They identified about 8,600 families of genes that corresponded to at least 14,000 human genes - or roughly 70% of the human genome.
One gene cluster preserved for more than half a billion years is though to be linked to the development of the pharynx - the passageway linking the nasal cavity to the mouth and throat - in both acorn worms and vertebrates.
Although the gene cluster is present in acorn worms and humans, it is missing from insects, octopuses, earthworms and flatworms.
Dr Oleg Simakov, from the Okinawa Institute of Science and Technology Graduate University in Japan, who led the study published in the journal Nature, said: "Our analysis of the acorn worm genomes provides a glimpse into our Cambrian ancestors' complexity and supplies support for the ancient link between the pharyngeal development and the filter feeding lifestyle that ultimately contributed to our evolution."