Studying Australian bearded Agam, inhabiting semi-deserts and forests of rare, scientists from the University of Sydney concluded that females of this species may disappear, yielding the so-called representatives of the third sex — the males from a genetic point of view and the females with physiological. His scientific work the researchers presented in the journal Proceedings of the Royal Society B.
In years when a summer is particularly hot, bearded agamids show a curious anomaly: the embryos of males in their eggs hatch females, almost indistinguishable from the normal behavior and physiology, but has a male set of chromosomes ZW. Ordinary females of this pack — ZZ.
The fact that the males of one species have a pair of different chromosomes, and females pair of the same – quite common in the animal world pattern. For example, in people women have a set of XX chromosomes and men XY. However, unlike most other species that have “exceptions” to these rules and rare individuals with “wrong” for their gender set of chromosomes are infertile, females Agam with the male chromosome not only able to lay eggs which hatch into offspring, but superior in fertility of normal females.
Due to the abnormally hot summer months, the recent habitat Agam, representatives of the “third sex” among them is increasing. This leads to the fact that the female chromosome contains at all a smaller amount of Agam, and therefore, with each new generation floor new individuals are increasingly determined solely by air temperature.
Comparing 55 males, 40 females and 20 Agam “third sex”, the experts noted that the latter was physically stronger, more active and more aggressive females, which can also help to ensure that these agamids are the usual females to displace.Related posts: