Home
http://www.ibtimes.com/elephant-shark-living-fossil-callorhinchus-milii-hardly-changed-400-million-years-1532708
The elephant shark isn’t really a shark at all. Rather,the large-snouted marine animal belongs to a group of fish called ratfish,which diverged from sharks about 400 million years ago. Scientists have called this group of cartilaginous fish “perhaps the oldest and most enigmatic groups of fish alive today.” Earth’s earliest fish species paved the way for bony skeletons,a sophisticated immune system and jaws.
Callorhinchus milii grow to around four feet. Elephant sharks,which occasionally get snagged in commercial fishing nets,typically live at depths of up to 650 feet. The fish spends most of its time on the ocean floor,where it rummages for crustaceans.
The fact that the elephant shark’s genome has stayed relatively unchanged means it boasts a genome very different from the genomes of vertebrates today. Scientists say this offers an extraordinary look into the evolutionary past of Earth’s vertebrates.
"We now have the genetic blueprint of a species that is considered a critical outlier for understanding the evolution and diversity of bony vertebrates, including humans," Wesley Warren,an associate professor of genetics at the Washington University School of Medicine in St. Louis,told AFP.
The elephant shark isn’t really a shark at all. Rather,the large-snouted marine animal belongs to a group of fish called ratfish,which diverged from sharks about 400 million years ago. Scientists have called this group of cartilaginous fish “perhaps the oldest and most enigmatic groups of fish alive today.” Earth’s earliest fish species paved the way for bony skeletons,a sophisticated immune system and jaws.
Callorhinchus milii grow to around four feet. Elephant sharks,which occasionally get snagged in commercial fishing nets,typically live at depths of up to 650 feet. The fish spends most of its time on the ocean floor,where it rummages for crustaceans.
The fact that the elephant shark’s genome has stayed relatively unchanged means it boasts a genome very different from the genomes of vertebrates today. Scientists say this offers an extraordinary look into the evolutionary past of Earth’s vertebrates.
"We now have the genetic blueprint of a species that is considered a critical outlier for understanding the evolution and diversity of bony vertebrates, including humans," Wesley Warren,an associate professor of genetics at the Washington University School of Medicine in St. Louis,told AFP.
