A fossil fish suggests early evidence for sexual reproduction
A new study published in Nature revealed that fish swimming 380 millions years ago may have sexual reproduction in a way similar to modern sharks.
The specimen from Australia belongs to an extinct group of fish known as placoderms (covered in tough armour) and has been named Incisoscutum ritchiei. This fossil specimen shows a modification of the pelvic fin on its belly. Such structure called a clasper is seen in modern sharks and would have been used by the male Incisoscutum ritchiei to grip the female during mating.
This fossil suggests that intern fertilisation evolved sooner than previously thought. Scientists expected that early fishes would show a more primitive type of reproduction with extern fertilisation. According to Dr Zerina Johanson from London's Natural History Museum "This discovery is incredibly important because evidence of reproductive biology is extremely rare in the fossil record".