Common in plants, this form of reproduction is quite rare in vertebrate animals. ![]() Parthenogenesis is a natural form of asexual reproduction in which the growth and development of embryos occur without fertilization by sperm. Their eggs, commonly referred to as "mermaid purses," are anchored to underwater structures or to the seafloor until the embryo fully develops and the pup hatches - usually about 160 days.Ī zebra shark at an aquarium in Australia actually produced viable offspring without ever having been with a sexually mature male. However, individuals tend to lay their eggs within a 112-day period, laying only 3-4 at a time. Zebra sharks are "oviparous," and since there is no distinct mating season, they can breed year-round. While many sharks generally need to keep moving so water will flow over their gills and provide oxygen, zebra sharks instinctively know to rest facing the current so they can efficiently pump water over their gills and breathe while remaining still. Even though adult zebra sharks also have spots, they were named as such because they have stripes as pups.ĭuring the daytime hours, they can be found resting on the ocean floor and are more active nocturnally as they hunt for food. Nonetheless, though the two species are similar, the leopard shark of the eastern Pacific looks very different, with their distinctive large patches outlined in black. In North America off the coast of California, there is another species ( Triakis semifasciata) already commonly called leopard shark, so using zebra shark for Stegostoma tigrinum is helpful. In this shark's case ( Stegostoma tigrinum), a zebra shark in North America would be correctly called a leopard shark in Australia. Binomial nomenclature names an animal using its Latin genus and species names, akin to a human's first and last name. In the scientific community, there is a globally agreed-upon naming process that helps prevent this kind of confusion. Common names for animals (and plants for that matter) can be seen as nicknames. However, in Australia, this same species of zebra shark is commonly and correctly called leopard shark. The zebra shark is at times misidentified as a leopard shark. When two species look similar or have common names that can be easily misassigned, there can be confusion. A zebra shark pup may be smaller than a foot at birth but can reach almost 12 feet as an adult, with its tail being half of its total length. ![]() As they mature, these stripes are replaced with small black dots and their body lightens to a tan. Zebra sharks are so named because the pups are born dark brown with yellowish stripes.
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