We finally have footage of tardigrade mating, and it’s even weirder than expected.
Scientists have captured the creatures mating for the first time, providing insights into the weird ways tardigrades reproduce.
The video shows that tardigrades perform a form of foreplay, described as ‘mutual stimulation’, before semen ejaculation and egg deposition, which can last an hour.
Scientists from Senckenberg Museum of Natural History in Görlitz, Germany analyzed the mating habits of the bisexual water bears to find out how exactly these practically unkillable creatures reproduce. The study which is the first detailed observation of the tardigrades sexual behavior has been published in the Zoological Journal.
Scientists observed that before the one millimeter-sized creatures got down to the business of semen ejaculation and egg deposition, the couple embraced in some “mutual stimulation.” That’s micro-foreplay, to me and you.
Then comes the money shot, when the male ejaculates onto the female’s outer layer of skin, and the eggs are laid. While this confirms fertilization happens outside the female’s body, the scientists say it’s not entirely clear how the semen reaches the eggs.
In some cases, no mating took place and the females reabsorb the eggs. Scientists note that, unlike their human counterparts, the male tardigrade can ejaculate semen several times during the hour-long process.
Further research is needed to gain a greater insight into the tardigrade’s reproduction processes and explain why the tiny creatures take part in foreplay, and how the sperm is directed appropriately.
Earlier this year Japanese researchers revived some water bears after they had been trapped in ice for thirty years. They went on to lay eggs and hatched healthy offspring despite being frozen for decades.