stupefying result have emerged from quotidian inherited testing at Chicago ’s Shedd Aquarium , where two pups were encounter to have been born through virgin birth despite there being tidy male in the tank car . The Miss Independent of zebra shark marks the second time this dodging of traditional means of procreation has been documented , dispute Assumption about the pros and cons of “ virgin birthing ” .
“ This is only the second event that we know of where sharks have been conduct by parthenogenesis even when there were tidy first mate usable , ” study generator Kevin Feldheim of the Field Museum of Natural History in Chicago said in astatement . “ This discovery throws a wrench in what we thought we knew about how and why parthenogenesis happens , and it illustrates a key aspect of science : we ’re continually learning . ”
The other incident ofparthenogenesisoccurring despite salubrious , and credibly eager , reproductive male being available was recorded at the Aquarium of Pacific . What make the decisiveness so interesting is that it was once consider a last - ditch effort to multiply when no likely mate were uncommitted , especially considering that sometimesparthenogenesiscan see resulting materialisation exhibit diseases and deformities bring on by recessive cistron .
Two zebra shark pups delivered a big surprise during routine genetic testing. Image credit: Gp258, Own work,CC BY-SA 4.0
Whether the move to reproduce without a mate is drive by life in captivity or something else is n’t yet absolved , but it could have big entailment for conservation work as well as menagerie and marine museum .
This discovery came about after twobaby zebra sharks(Stegostoma fasciatum)waggling their manner through the urine of Chicago ’s Shedd Aquarium were found to have homozygous alleles , meaning that the two set of transmissible material that are usually kick in by a male and distaff both came from the same parent . Normally , having an allelomorph from each parent results in at least some edition – so when it demonstrate up that the puppy had identical alleles throughout , it was clear they were n’t the product of sexual reproduction .
The telling feat is a vex one , and alas come with considerable downsides for the offspring . intimate procreation can help to mash rare transmissible conditions that are carried by recessionary alleles as there ’s a luck for the other parent ’s predominant allele to override it . If both sets of alleles are coming from one parent then they will be the same , and so even recessive conditions will become the predominant phenotype .
The whelp in this study only hold up a few month , but that they were able to be bear at all is still fascinating as it dispute some of our savvy as to how life , uh , finds a mode .
“ Discovering these pup were parthenote was quite a surprise for the squad at Shedd , given our old success in further breeding through sexual reproduction,”said Lise Watson , help managing director of animal performance and habitats at Shedd Aquarium and an author of the written report . ” This newsworthiness underscored just why steady , ongoing genetic examination of offspring is important . ”
“ This cogitation is just the beginning of our reason of the natural event of this genic phenomenon in zebra shark . ”
The study was published in theJournal of Fish Biology .
