Brave mantis males wrestle with their female mate not to be eaten, a new study reveals.
New Zealand researchers have looked at the mating behavior of the highly cannibalistic springbok praying mantis (Miomantis caffra), a type of praying mantis.
Praying mantis has the reputation of cannibalism because females often eat males before they get a chance to mate.
But in this particular species, the male and female struggle in a ‘violent struggle’ before mating, as each mate tries to be the first to grab the other with its front legs.
If the female wins, it spells almost a certain death for the male, but if the male wins, it increases his chances of mating successfully, dramatically, while often injuring the female.
Instead of avoiding cannibalism by being shy and cautious, males can overcome the threat of cannibalism by ‘wrestling females’, the experts say.
60 percent of the sexual encounters between springbok mantises – which is one of nearly 2,000 praying mantis species around the world – end up in males that are eaten.
Incredible video footage shows the noble male with the larger female scraping inside cups in a laboratory.
Red arrow indicates a healed abdominal wound to a springbok praying mantis female after an encounter with a male
The study provides the first evidence of forced mating in a mantis.
“Men play Russian roulette when they encounter cannibalistic females,” said Dr. Nathan Burke, study author, an entomologist at the University of Auckland and an expert on mating rituals for mantis said.
‘It is rare for males to avoid cannibalism through this form of coercion – to physically fight with females to mate successfully – and this is the first evidence of this behavior in a cannibalistic mantis.
‘Sexual conflict in the insect world is not so uncommon and usually favors a cautious or tactical approach.
“But the springbok male male is really fighting to achieve his goal, and this study shows that it may be the best option in terms of reproductive success.”
Male (top) female (bottom) Miomantis caffra mating in Auckland, New Zealand. The female’s belly bulges visibly as she lays eggs from a previous mating encounter
The springbok prayer locust is native to southern Africa, but is commonly found in New Zealand after being first identified there in 1978.
For this study, researchers collected 52 pairs of springbok mantises and observed their behavior over a 24-hour period in the laboratory.
“All individuals were housed in individual gates and fed three to five houseflies (Musca domestica) three times a week,” Dr. Burke and his Auckland co-author Professor Gregory Holwell wrote in their paper.
“For mating trials, our adult virgin males and females mated in an inverted 700 ml clear plastic beaker and observed their behavior.”
They found that 29 out of 52 couples (56 percent) had physical contact between the sexes within the first twelve hours.
The male was always the first to start contact and did so by jumping on the female while fluttering his wings quickly.
Nearly all – 90 percent – increased in physical combat, lasting an average of 12.77 seconds.
Of these, 7 percent led to separation without a winner.
A female Miomantis caffra monster laying her eggs. The species is a moderately sized prayer locust with one of the best known doses of pre-copulatory cannibalism. More than 60 percent of sexual interactions end in the fact that men are consumed, mostly without mating
35 percent of the fight resulted in the female grabbing the male first, and all such fighting resulted in cannibalism.
Men were the first to grab women in 58 percent of the fight.
Of these, 67 percent ended with mating (half of which ended with cannibalism thereafter), 13 percent with cannibalism without mating, and 20 percent with non-cannibalism or mating.
On several occasions, females who have lost the fight have tried to grab attached males, but they do not succeed.
Another unusual finding was that 27 percent of the females who lost the fight were injured by the male’s predictable claws.
This resulted in severe abdominal lacerations that later formed black crusts – something that was also observed in women in the wild.
Researchers believe the ‘intimidating and harmful nature’ of male wrestling behavior suggests that it is a form of ‘sexual coercion’ with which men force women to mate.
“We’ve learned a lot of fascinating biology from Miomantis caffra over the last decade, but this latest work is truly amazing,” said Professor Holwell.
“This is the best example of men fighting back to face the risk of sexual cannibalism.”
The study was published in the journal Biology Letters.