The female giant spider ( Nephila pilipes ) that lives in forests in Asia and northern Australia make a kind of plugs to protect themselves from superfluous and unwanted sexual encounters , according to research published in the journal PLos ONE .
In the animal world, the competition to reproduce and pass genes on to offspring is fierce. Many examples of extreme cases are known in which males, after copulating, break their genitalia inside the female, in such a way that a plug is produced that prevents subsequent copulations with other males.
However, an international team of researchers has given a twist to the matter and has found a case in which the females themselves produce these plugs. As the authors explain, plugs are produced after fertilization of the eggs . In this way, unnecessary sexual encounters are avoided and above all very expensive in terms of energy, since in this species several mating episodes are needed to produce the fertilization of the eggs.
To reach these conclusions, the scientists studied in laboratory conditions the mating of several female spider with different males, observing that after a single sexual encounter no plugs were produced , but rather that they appeared during the laying of the eggs and after having copulated with several males.
