Wednesday, December 25, 2019

How Do Insects Have Sex

Insect  sex is, for the most part, similar to other animal sex. For most insects, mating requires direct contact between a male and a female. Generally speaking, much like humans, the male of the insect species uses his sex organ to deposit sperm into the females genital tract spurring on internal fertilization. But there are some standout cases where males and females make no contact at all. Wingless Insects The primitive insect order (Apterygota) relies on an indirect method  of sperm transfer to its mate. There is no insect-to-insect contact. The male deposits a sperm packet, called a spermatophore, on the ground. For fertilization to occur, the female must pick up the spermatophore. But there is a bit more to the males mating ritual than just dropping some sperm and running. For example, some male springtails go to great lengths to encourage a female to pick up his sperm. He may nudge her toward his spermatophore, offer her a dance or even impede her path away from his sperm offering. Silverfish males attach their spermatophores to threads and sometimes bind their female partners to force them to accept their sperm package. Winged Insects Most of the worlds insects (Pterygota) mate directly with the male and female genitalia coming together, but first the couple must attract a mate and agree to mate. Many insects use extensive courtship rituals to choose their sexual partners. Some flying insects can even mate midflight. To do so, the winged insects have a unique sex organ for the task. After a successful courtship, copulation occurs when the male inserts part of his penis, also known as an aedeagus, into the females reproductive tract. In many cases, this requires two steps. First, the male extends its penis from his abdomen. Then, he extends his penis further with an inner, elongated tube called the endophallus. This organ acts as a telescoping penis. This extension feature enables the male to deposit his sperm deep within the females reproductive tract. Satisfying Sex One-third of insect species studied by scientists show that the males do not seem to neglect their  partners either. There seems to be a decent effort on the males part to make sure the female is pleased with the sexual encounter. According to Penny Gullan and Peter Cranston,  Ã¢â‚¬â€¹entomologists from the University of California-Davis, in their textbook The Insects: An Outline of Entomology: The male indulges in copulatory courtship behavior that appears to stimulate the female during mating. The male may stroke, tap, or bite the body or legs of the female, wave antennae, produce sounds, or thrust or vibrate parts of his genitalia. Another example, milkweed bugs, also known as Oncopeltus fasciatuas, may copulate for several hours with the female leading and the male walking backward. Everlasting Sperm Depending on the species, a female insect can receive sperm in a special pouch or chamber, or a spermatheca, a storage sac for sperm. In some insects, such as honey bees, the sperm remains viable for the remainder of her life in the spermatheca. Special cells within the spermatheca nourish the sperm, keeping it healthy and active until needed. When the bees  egg is ready for fertilization, sperm is pushed out of the spermatheca. The sperm then meets and fertilizes the egg.

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