shark are pretty unbelievable creatures . And the more we read about them , the more particular they become . You might make out , for example , that sure species give birth to live youthful and that some female sharks have a left and good womb . What you might not get laid is that shark fetuses can float from one uterus to the other . And they can do so pretty rapidly .
As reported in the journalEthology , sonograms of significant tawny nurse sharks conduct at the Okinawa Churaumi Aquarium in Japan revealed the unbelievable feat . The reason for this is unclear but the explanation put forrad by the researchers is quite grisly . Some shark feed in their foetus through oophagy , meaning the not - yet - born baby shark feed in on eggs in the womb , and sometimes even their siblings . The power to go and hunt for more testis might be cardinal to a skillful chance of survival of the fittest .
This behavior inside the uterus is quite unlike what we have see in mammals . Mammal fetuses are quite stationary while these shark pups can drown up to 8 centimeters ( 3.1 inches ) per secondly . The research necessitate several years to complete and focus on three pregnant tawny nurse sharks . The squad collect 40 ultrasounds cartridge clip , prove the real apparent motion and also the variety of scenario that developed inside the womb . One female parent had embryos that swop side three times , another ’s young did so 24 times . The researchers even witnessed a pregnancy where the pups went from two in each uterus to a single ( but well - fed ) pup .
The squad also chance on that tawny nursemaid sharks can sometimes open up their cervixes to countenance their puppy to station their snouts outside the uterus if they desire to . This is very unlike from what happens in mammalian pregnancies . The cervix of expectant female mammalian is tightly shut until birth .
This report was only possible thanks to the development of the submersed ultrasound . This twist allowed reflection of the pregnancy in the less - nerve-racking surround of the creature ’s tank . late observation have involved really take away the shark from the water , clearly not an ideal place to study " regular conduct " . To work , the simple machine had to be both waterproof and able to hold up the pressure at the bottom of the storage tank . The new ultrasonography is a necessary requirement for the underwater OB - GYN and will permit for even more interesting subject .
[ H / T : Live Science ]
