This behavior is believed to have evolved as a manifestation of sexual conflict, occurring when the reproductive interests of males and females differ. In many species that exhibit sexual cannibalism, the female consumes the male upon detection.
In a grisly practice known as sexual cannibalism, females of many spider species devour their mates after procreation, either for sustenance or to keep their reproductive options open. Female spiders are usually much larger than their male counterparts and thus have a strong physical advantage.
Mating of spiders is not always followed by cannibalism. Indeed, scholars have noted that the "supposed aggressiveness of the female spider towards the male is largely a myth" and that cannibalism only occurs in exceptional cases.
Treat them mean, keep them keen? Female praying mantis and black widow spiders are notorious for their tendency to kill and eat males before, during or after sex.
After copulating with a male, female spiders tend to practice sexual cannibalism, that is to say, they attack the males and eat them.
After mating, the males of some species smear a secretion over the epigynum, called an epigynal plug, that prevents the female from mating a second time. Male spiders usually die soon after, or even during, the mating process.
Although adult male spiders are like vertebrates in having a pair of abdominal testes, their genital apparatus only vaguely resembles that of a vertebrate.
Male kalutas, small mouselike marsupials found in the arid regions of Northwestern Australia, are semelparous, meaning that shortly after they mate, they drop dead. This extreme reproductive strategy is rare among vertebrates —only a few dozen are known to reproduce in this fashion, and most of them are fish.
Parthenogenesis is a form of asexual reproduction. Stick insects (Phasmatodea) are not the only insects that can produce asexually. There are also aphids, water fleas (Daphnia sp.), nematodes, plants, snakes, the whiptail lizard Cnemidophorus neomexicanus and more species that reproduce through parthenogenesis.
All aphids — large or small — are able to reproduce asexually. Through a phenomenon called parthenogenesis, their embryos can develop from unfertilized sex cells. Such "virgin births" have also been documented in anacondas and zebra sharks — to name a few.
The same 2002 study found that some male redbacks had evolved to “somersault” during copulation, twisting their abdomens on to the fangs of their mates in what was construed as an “adaptive male strategy of self-sacrifice” that, if they were eaten, increased their chances of paternity.
Welke said. During mating, a male's pedipalp, the organ that transfers sperm, breaks off in the female and forms a plug. This prevents subsequent males from fertilizing eggs. Each male spider has two pedipalps, allowing him to mate twice in a lifetime.
The male's pedipalps are modifed to store sperm before mating and then squirt them into the female's copulatory openings. After mating, sperm are held in a pair of pouches (spermathecae), until the female begins to release eggs from her ovaries.
When most spiders mate, the male ejects sperm into the female's genital organs, and the sperm is then stored in a pouch called the spermatheca. She releases the sperm later to fertilize eggs in the uterus—so the last male to mate with her will most likely father her offspring.
Males ejaculate onto ready-made small sperm webs and then transfer their sperm to syringe-like structures on the tips of their front appendages, or palps. As courtship progresses for the male jumping spider, he will arch his body, and slink on tiptoe toward the female.
Now scientists find that male dark fishing spiders (Dolomedes tenebrosus) apparently sacrifice themselves to females after mating to aid their offspring, as reported online October 6 in the journal Current Biology.
There is only one insect that can turn its head – the praying mantis.
Apis dorsata (Hymenoptera:Apidae) is here named as the most polyandrous insect because it has been recorded to mate up to 53 times, each with a different male.
Most insects reproduce by sexual reproduction. The female produces eggs, which are fertilized by the male, and then the eggs are usually placed near the required food. In some insects, there is asexual reproduction during which the offspring come from a single parent.
Not only do animals enjoy the deed, they also likely have orgasms, he said. They are difficult to measure directly but by watching facial expressions, body movements and muscle relaxation, many scientists have concluded that animals reach a pleasurable climax, he said.
Mules can't reproduce. Here's the biological explanation why. Belleville News-Democrat.
In 1913, male bedbugs were first observed using their needlelike penises to puncture the females' exoskeletons wherever they could during sex. Sperm is deposited into the wound, where it travels through her body fluid to the ovaries.
Reproduction: Females mature at 3-4 years, males slightly younger. Receptive females will allow a male to mate, usually during the rainy season, resulting in an egg sac containing 300 – 500 eggs laid several weeks later. The sac is incubated in her nest for about 7-8 weeks.
Tarantulas Just Aren't That Into You
Spiders do have feelings, but unlike a dog or a cat, they won't bond with you. In fact, they likely won't even recognize you. They simply aren't hardwired to be companions to humans and should never be bought at pet stores, online, or anywhere else.
After pouncing on some prey, a tarantula stabs it with two hollow fangs. Then the tarantula squirts venom through its fangs and into the prey to kill or paralyze it.