The bigger the horn, the smaller the quarter's

The beetles with the largest horns also have the smallest testicles. This suggests that in terms of evolution, this will lose something else. The result is clear evidence of a trade-off between the ability to compete for partners with fertility.

(Photo: ABC Online) Professor Leigh Simmons at Western Australia University and American professor Douglas Emlen at the University of Montana investigated the beetles of the Onthophagus genus.

"These beetles need big horns to fight against their children and they also need great testers to win the sperm competition ."

"But they can't have both, so those who invest heavily in horns are inferior in their sperms . "

The study also demonstrates the hypothesis of sperm competition, which occurs when females mate with more than one partner. Hypothetically, the male-to-male confrontation continues after the partner has been chosen, since the sperm from different animals are competing to fertilize the egg.

Simmons conducted an experiment in which the horn growth area of ​​the young beetle was burned and disintegrated cells and prevented horn growth. He realized that if the horn was inhibited, the animal would be compensated with larger testicles.

"They only have a certain resource to distribute to different structures, to the legs, wings, horns, testes and other important parts," he explained.

Other research has also shown that bats change the size of the testicles to get intellectual powers.

MT