New genetic evidence suggests the evolutionary origins of human limbs lie in the gill arches of sharks skates and rays. Gill arches are the collection of looped bones that support gills and serve as the sprouting point for gill arch appendages or branchial rays.

See the source article by following the link below:New genetic evidence suggests the evolutionary origins of human limbs lie in the gill arches of sharks, skates and rays. Gill arches are the collection of looped bones that support gills and serve as the sprouting point for gill arch appendages, or branchial rays.