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Sharks' reproductive organs serve to reproduce sexually where the male delivers sperm to the female using claspers that insert into the female's oviduct. This then allows the female to give birth to live young, although some do lay eggs.
Parthenogenesis in sharks has been confirmed in the bonnethead [35] and zebra shark. [36] Other, usually sexual species, may occasionally reproduce parthenogenetically, and the hammerhead and blacktip sharks [37] are recent additions to the known list of facultative parthenogenetic vertebrates. A special case of parthenogenesis is gynogenesis.
Sharks generally reach sexual maturity only after many years and produce few offspring in comparison to other harvested fish. Harvesting sharks before they reproduce severely impacts future populations. Capture induced premature birth and abortion (collectively called capture-induced parturition) occurs frequently in sharks/rays when fished. [74]
“The shark scientists were not really happy with that press release. No one would even think of that as an option.” ... (the cells that create new organisms in sexual reproduction) are created ...
Some species reproduce exclusively by parthenogenesis (such as the bdelloid rotifers), while others can switch between sexual reproduction and parthenogenesis. This is called facultative parthenogenesis (other terms are cyclical parthenogenesis, heterogamy [ 14 ] [ 15 ] or heterogony [ 16 ] [ 17 ] ).
In 2007, the bonnethead shark was found to be capable of asexual reproduction via automictic parthenogenesis, in which a female's ovum fuses with a polar body to form a zygote without the need for a male. This was the first shark known to do this. [19]
Greenland shark reproduction remains mysterious, according to Britannica. Scientists believe that females begin reproducing after reaching about 13 feet in length — or about 150 years in age.
Parthenogenesis is a mode of asexual reproduction in which offspring are produced by females without the genetic contribution of a male. Among all the sexual vertebrates, the only examples of true parthenogenesis, in which all-female populations reproduce without the involvement of males, are found in squamate reptiles (snakes and lizards). [1]