Polyandry: Matriarchy Of The Animal Kingdom
Polyandry is the reproductive strategy carried out by some species, where the female copulates with two or more males to ensure offspring.
Breaking the myth of monogamy
The benefits of polyandry
- More sperm and more genetic variability.
- In species with sperm competition (the sperm of several males compete to reach the oocyte within the female), greater viability of the offspring is ensured.
- Some studies show that the presence of different semen increases the strength of the embryo or embryos, through genetic mechanisms. For example, to promote the selection of sperm with “more compatible genes”.
- In some species, males offer food to females as part of courtship, increasing the female’s fecundity.
- Polyandry appears to increase the scope of parental care on the part of the male.
- Lowers the risk of infanticide. The fact that the males are not sure if the young are theirs prevents them from wanting to kill them in order to copulate with the female again.
- There are genetic mechanisms that promote the selection of sperm with “more compatible genes”.
How does polyandry affect males?
- In some species the males protect the females to prevent a competitor from arriving.
- They can also insert plugs at the entrance of the female’s vagina to prevent her from copulating with other males. This is the case with rats and mice.
- In other species, males can control the amount of sperm they ejaculate based on the number of potential competitors.
- Some males secrete, together with the sperm, proteins that cancel the receptivity of the female or accelerate the laying of eggs (in oviparous species).
