Chinese and Australian scientists have found that embryos of certain species of turtles can "choose" their sex, moving inside the egg. This was reported in the journal Current Biology.

Professor Du Weigo of the Chinese Academy of Sciences notes that the results of the experiment allow researchers to better understand how reptiles adapt to new climatic conditions resulting from global warming.

“Earlier, we demonstrated the ability of reptile embryos to move inside the egg for thermoregulation, and we wondered if this could affect the determination of their sex,” Du Weigo said. “We wanted to find out if this behavior can mitigate the effects of global warming on the sex ratio among the offspring of these species, and if so, how.”

During the experiment, scientists proceeded from two well-known facts. First, the sex of newborn turtles depends on the incubation temperature of the eggs — at lower embryos, they develop into males, and at higher ones, into females. Secondly, reptile embryos are able to change their position inside the egg, moving to warmer or cooler zones.

Scientists incubated several batches of turtle eggs at different temperatures in laboratories and in vivo. They treated half of the eggs with capsazepine, a substance that blocks temperature receptors.

After the turtles were born, the researchers calculated the number of males and females in each batch. Experts have found that from eggs treated with capsazepine, the young of the same sex basically hatch - either males or females, depending on the incubation temperature. In the untreated batches, that is, in conditions where the embryos could feel the temperature and regulate it, changing their position in the egg, the ratio of males and females was approximately equal and did not depend on external factors.

The results of the experiment showed that turtle embryos can "change" the temperature of their body by almost 5 ° C. At the same time, the sex of the embryos changes even when it is raised or lowered by more than 2 ° C.

“The most interesting thing is that the embryo, moving inside the egg, is capable of influencing the determination of its own sex,” says Du Weigo.

One of the co-authors of the work, Professor Richard Shine of Macquarie University (Australia), writes that embryos tend to get to the place inside the egg, where it is not too hot or cold. The scientist calls it the “Goldilocks Zone”.

  • Baby turtle
  • Reuters
  • © Denis Balibouse

Such behavior of reptile cubs will help specialists understand how turtles survived during periods when average temperatures on Earth were much higher than they are now, the professor says.

As Du Weigo notes, evolution lays in some species of animals the ability to respond to such challenges. According to the scientist, a number of creatures may have other strategies to combat global warming, which have yet to be established.