The large number of coatings of vipers

1992/09/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria

• Biologia

In nature are insects, birds, reptiles and female mammals, which are subsequently covered by many males. The reasons for this fact are not yet clear.

It seems that only one could be covered. And it is that for the female the coating (at least from the energetic point of view) can be very laborious.

A group of Swedish ecologists have been studying the type of viper "Vipera berus" for ten years. According to these ecologists, as the number of coverages increases, the number of born offspring is greater.

How have ecologists made this decision?

After each mating, the females store the sperm of the male in the genital tract. The sperm will not be released until after a few months, just until ovulation. The researchers say that there is a relationship between the number of rigs and the number of dead born vipers, that is, the greater the number of rigs, the less young are born dead.

Although what is said is evident, it is difficult to demonstrate why it occurs. It seems that there is a competition between the spermatozoa and that the best of that competition arrive to the egg. Therefore, the more coverage you have, the greater the number of good sperm.

Saying this is one thing, but trying another. The test will be done by analyzing the genetic fingerprints. Therefore, the path for new research is open.