Like skates and rays, they belong to a group known as elasmobranchs. Sharks A family of primitive fishes that rely on skeletons formed of cartilage, not bone. Rays (in biology) Members of the shark family, these kite-shaped fish species resemble a flattened shark with wide fins that resemble wings. Parthenogenesis An unusual form of reproduction where animals sometimes produce healthy offspring from an unfertilized egg. People who work in this field are geneticists.
The field of science dealing with these biological instructions is known as genetics. Genetic Having to do with chromosomes, DNA and the genes contained within DNA.
Power Wordsįertilize The merging of a male and a female reproductive cell (egg and sperm) to set in create a new, independent organism. It’s just another example of the wonders of biology - like last year’s “ Octomom.” She was an octopus that spent a world-record 4.5 years guarding a clutch of eggs on the seafloor off of California, at a depth of 1,397 meters (more than eight-tenths of a mile). “Unfortunately,” Bernal’s group reports, “there is no information on the whereabouts of the sharks that shared the enclosure with the three females from this study.” Who that dad is and where he is now remains a mystery. DNA tests showed that although the pup was closely related to one female - its likely mom - it also contained genetic material from another individual. But that didn’t happen here, Bernal’s team concluded. It lets a female produce young even when there are no males around. This unusual strategy can sometimes make sense, biologists argue. And this type of reproduction has occurred before in at least three types of sharks: the bonnethead, blacktip and whitespotted bamboo species. This is called parthenogenesis (PAR-then-oh-JEN-eh-sis). The females of certain animals sometimes can produce offspring from an unfertilized egg. So the researchers puzzled over how this shark pup came to be.Ĭould the ray have been the pup’s dad? The scientists rejected that idea pretty quickly: The two species are so distantly related that it should have been nearly impossible for them to mate and produce live offspring. Eleven months later, two of those egg cases showed signs of a live, developing shark inside. (Rays are members of the shark family and resemble flattened sharks with wings.) In January 2011, the brownbanded bamboo sharks laid egg cases - nicknamed mermaid’s purses. There, they shared a tank with female blacktip reef sharks and a male Javanese cownose ray. When new facilities at San Francisco’s Golden Gate Park opened up, the three females moved in. At the Long Beach facility they had shared a tank with male brownbanded bamboo sharks.Īfter leaving Long Beach, the female sharks spent a year in a temporary home. They came from an aquarium in Long Beach, Calif.
The Steinhart Aquarium got the tank’s three female sharks in September 2007.
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