I bet you will be grateful for being a human after knowing about traumatic insemination! As the name suggests, traumatic insemination is quite an unusual way of insect mating and is indeed traumatic, in its procedure. The entire act is ideally beyond logic and appears to be brutal. But that is the way it is, in the animal world, suited for animal adaptations.
Mites, bedbugs and even some spiders indulge in this copulation technique that is probably the most traumatic form of mating. In the act of copulation, the male insect pierces his penis or genitals in the abdomen of the female, forcefully, and injects the sperm in the wound formed after the piercing. The sperm reaches directly through the abdominal cavity to ovaries for fertilization by the help of hemolymph, a fluid found in the circulatory system of many insects of the arthropod family. In the animal kingdom, this form of mating is not limited to male - female copulation but it has also been observed in homosexuals. Homosexual traumatic insemination is observed in few insects like flower bug or Xylocoris maculipennis.
Substantial Losses to the Female Partner...
The process as stated earlier, is quite taxing for the female insects. Even though we may try to give explanations regarding the reason behind such an act, it has been found that female insects after this type of copulation experience health issues. Although this process benefits the reproductive cycle of the particular insect species, the female partner faces the possibility of reduced lifespan and reproductive health issues. After the act, the female gets injured in the abdomen and blood loss occurs through the abdomen. It has also been observed that female insects face the risk of infections due to open wounds. Even the immune system of female insects has been found to be poor due to traumatic insemination.
Why Such a Brutal Battle of Sexes?
It is very difficult to know the exact reason behind such mating practices in the insect world. However, scientists have tried to related this unusual method of reproduction to evolutionary theories. Traumatic insemination in bed bugs is a popular method of mating and it is related to their adaptation. Scientists believe that traumatic insemination is an alternative adaptive way to mating plugs, that are gelatinous secretions used during mating of many insect species. After copulation, the male insects deposit a secretion in the female genital tracts, that hardens over time and forms a plug. This helps in increasing the chances of fertilization as the sperms stay in mating plug and as long as sperms are in the reproductive tract, there are higher chances of fertilization. Traumatic insemination is a more faster method of mating than 'mating plugs' because in this act, the male directly pierces the abdomen and enters the sperm in the female's body. Some people believe that male insects use traumatic insemination as a way to avoid courtship time and directly mate with the partner. By directly mating with female insects, males have the advantage of mating many partners in a short period of time. This helps in reproduction and continuation of the species.
Similar mating practices exist in many other species of the animal world, where there is no place for courtship or spending time with each other. It is believed that in species like bottlenose dolphins, young males in groups chase a female dolphin to force her to copulate. In some arachnids, females kill the male after copulation or even during the act!! So didn't you find traumatic insemination a bizarre mating act? The rules of animal world are quite different and studying them closely gives us the realization that, this world is one big mystery!