![]() Since they are most active at night, zebra sharks spend the daytime hours resting on the ocean floor and facing the ocean current so they can move water across their gills and continue breathing while remaining almost completely still. In the National Marine Sanctuary System, zebra sharks live near the National Marine Sanctuary of American Samoa and Rose Atoll Marine National Monument. They have been observed at depths of about 180 feet and they often stay close to their home reefs. Zebra sharks are primarily found in the Indo-Pacific region of the global ocean and live along coral reefs where food is usually plentiful and conditions are just right. Their flexible bodies allow them to bend and fit into tight spaces where small fish might hide. With their small mouths and powerful gill muscles, zebra sharks easily vacuum up their prey in a single gulp. To find their prey, which are often on the seafloor or buried in the sand, they rely on their barbels to help them detect their target’s movements. Zebra sharks are nocturnal foragers that rely on small fish, snails, sea urchins, crabs, and other small invertebrates for their dietary needs. Their long tails resemble a knife blade but these sharks are quite docile and can even act skittish around divers. When they are born, they are covered in yellowish stripes that are eventually replaced with brown spots that resemble those of a leopard when they reach maturity. They have small barbels (whisker-like sensory organs near their snouts, a small mouth with small teeth that are regularly replaced, and tiny eyes. Zebra sharks are long and sleek, reaching lengths of nearly 12 feet when fully grown, with their tails making up nearly half of their body length. ![]() In some areas, these sharks are called leopard sharks due to their spots, which can be confusing because there is also another species of shark that lives in the Pacific North American Coast with this moniker. According to Kevin Feldheim, a co-author of a 2010 article in the Journal of Heredity on parthenogenesis in sharks, it might be a response to the absence of reproductive partners.Z is for zebra shark ( Stegostoma tigrinum), a long, sleek species of shark that is born with stripes that turn into spots as they age. Scientists don’t know for sure why sharks, snakes, and other creatures that normally need to mate to reproduce will sometimes just spontaneously get pregnant. Further tests, however, revealed that the pups’ lack of genetic diversity meant they were most likely the spawn of one parent, not two. And so when the zebra shark gave birth, scientists at the Queensland aquarium also wondered if stored sperm was to blame. In the snake’s case, her offspring couldn’t have been fertilized by sperm, because she had never been near a male. ( Read “World's Longest Snake Has Virgin Birth-First Recorded in Species.”) When a reticulated python had a “virgin birth” at the the Louisville Zoo in Kentucky, scientists were so surprised that they at first wondered if this was a case of stored sperm. Yet after three years of separation from a male, scientists were stunned to see some of her eggs hatch.Īlthough this switch from sexual reproduction to parthenogenesis-reproduction without fertilization-is a first for sharks, it has also been observed in a spotted eagle ray and a Colombian rainbow boa.Īsexual reproduction without prior sexual reproduction has also been observed in plenty of creatures that don’t normally do it that way. In her new tank, Leonie continued to lay eggs whether they were fertilized or not, just like chickens do. In 2012, she was moved into a separate tank at the aquarium with no male sharks. Leonie had previously given birth after mating with a male shark at the Reef HQ aquarium in Townsville, Queensland. ![]() ( Read “‘Virgin Birth’ Record Broken by Hotel Shark.”) This isn’t the first time that a zebra or leopard shark ( Stegostoma fasciatum) has had a “virgin birth,” but it is the first time that scientists have seen this behavior in a shark that wasn’t, ahem, a virgin. ( Read our earlier story about the birth.) ![]() ![]() Scientists in Australia published a paper on Tuesday about a female shark that performed a “virgin birth.” Although she hadn’t been around a male shark in three years, the captive zebra shark-named Leonie-laid eggs that hatched three viable pups. ![]()
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