The bloodthirsty, serrated-teeth-baring predator of the sea. The ocean’s one and only menacing torpedo of muscle and primal hunger. The mascot of that one annoying kids bop: Sharks. Whether they rivet or repulse us, based on scientists' ongoing discoveries on this cartilaginous fish, one fact remains undeniable: they’re pretty darn cool. I’m sure that by the 6th grade you have all been educated on a concept widely known as ‘the birds and the bees’. However, what if I were to tell you that, although rare, reproductive eggs in some species do not solely rely on male fertilization to produce offspring. To all the single ladies indeed!

Parthenogenesis, greek for ‘virgin birth’, is a phenomenon that occurs when a female egg cell develops into a zygote without fertilization by a male sperm. Although, similarly to hermaphrodites, the concept of parthenogenesis revolves around a sole parent being involved in the formation of offspring, the two are not to be confused as the former refers to an organism that reproduces through means of self-fertilization whereas the latter is used to describe conception bereft of any sort of fertilization. This means of reproduction is considered quite rare, especially amongst vertebrates - in fact, it was essentially unheard of in cartilaginous fish. However, it has been observed by scientists in species of Shark such as zebra sharks, bonnetheads and blacktips.

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The process of parthenogenesis involves a sub-process known as ‘automixis’ or ‘automictic parthenogenesis’. During meiosis, a gamete will reproduce to form more of its kind. However, typically, only one will actually become an ovum whereas the rest of the gametes - deprived of nutrients and cytoplasm - turn into non-functioning polar bodies. Next, one of these polar bodies fuses with the ovum, resulting in the stimulation of embryonic development. Genetic material is exchanged during this due to chromosomal crossing over, resulting in offspring that are considered ‘half clones’ of their mothers simply because half of their genetic variation comes from genetic material pre-determined in the ovum.

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One of the major caveats of parthenogenetic reproduction in Sharks is that seeing as all parthenogenetically derived offspring end up with two copies of the same allele for their genes, they are of the homogametic sex - thus female. This significantly reduces genetic variation amongst parthenogenetically derived organisms.

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Although the frequency of the occurrence of this phenomenon in the wild is yet to be explored by researchers, scientists hypothesize that it’s likely not uncommon in major Shark populations. Another point that has yet to be revealed is to which species of Shark this process particularly applies to. All of them? Or is it simply a select few? Nevertheless, with populations on major decline due to increasing demand for their fins, the discovery of self-reproducing females in Sharks could not have better timing as experts might suggest it to be a great alternative reproductive strategy. Whether this unique gift can be considered a blessing or a curse, these untamed, forceful beasts of nature have stumped researchers and learners worldwide.