Scientists have explained the relationship between the strength of the male-roaring howler and eggs – Express-News

23.10 | 22:09

Scientists, naturalists have established the American howler monkeys an interesting correlation between the strength of the voices of the male and his sexual organs. It turned out, the louder the voice of the male, the lower his testicles. Scientists attribute this to the fact that “gorlatomu” the male has to exert less effort to attract females.

«It is possible that the contribution of resources in the development of a powerful roar and related bodies during the growth of baby leaves no energy for the development of large genitals. On the other hand, it may be true that a powerful bond and sip as efficiently distilled off other males and attracts females that their owners do not need to acquire a large testicles “- said Jacob Dunn of Cambridge University (UK).

howler monkeys – primates average size, their weight is only 6.7 kilograms. A distinctive feature is the extremely loud, deep growl. This roar is useless in terms of survival, but it helps to extend his male gender. Charles Darwin once considered howler monkeys a clear example of the evolution of sex in animals. Jacob Dunn agreed with his colleagues to test this hypothesis the founder of the theory of evolution, which was organized by the observation of the behavior of nine species of howler, the study of the structure of their body.

In the course of observations, scientists have noticed that the males – the owners of the most profound and formidable roar, we had a relatively small testicles. After examining the structure of their vocal cords, larynx and other parts of the body, the researchers found that the size of the testicles, and even then, public groups live howler, it all depended on how large was the hyoid bone. If this bone was small, the testicles in males were large enough that allows them to live in large flocks howler with several males. Contrary to these individuals, males with a large hyoid bone, lived in the company of a small “harem” of several females.

This bone is a “cavity”, reinforcing the roar of the male. The formation of this bone requires large resources, which may influence the formation of relatively small genitals.

Currently, Dunn and his colleagues are studying the shape of the bones in different kinds of howlers. But scientists believe that in any case, Darwin was right – the roar of howler really is a consequence of the sexual evolution that made different kinds of monkeys to choose the opposite strategy of the struggle for the attention of females.