But her signals are deceptive. While they promise sex, the female's real quest is to eat the male so she has the energy to reproduce, says evolutionary biologist Dr Kate Barry of Macquarie University.
"The male is quite a large meal compared to any other prey type that the female would consume, and they can therefore use those resources to produce more eggs and have more babies," says Barry.
For a couple of decades now, some scientists have believed that malnourished female mantises can use sex pheromones to deceptively attract males so they can cannibalise them for food.
But studies to date, including two by Barry herself, have not supported this Femme Fatale hypothesis.
Instead, research has found that the more nourished a female mantis is, the more pheromones she produces. And poorly-nourished females have not been found to attract more males than those that are well-nourished.
This has led many scientists to conclude that a female needs to be well-nourished to produce pheromones, and that these chemicals are a reliable signal to males that a female is in good condition, with lots of eggs, and is likely to be a good mate.
However, Barry was still convinced hungry females were practising chemical deception but the design of experiments was just failing to pick this up, so she set up a new experiment designed to make up for what she saw as defects in earlier studies.
She put three groups of eight female false garden mantids (Pseudomantis albofimbriata) in cages made of mesh, which obscured the females from sight.
Each group of eight included females whose nourishment status was either 'very poor', 'poor', 'medium' or 'good'.
Barry then watched what happened as she released males around the caged females.
She found that for the 'poor', 'medium' and 'good' groups, the higher the nourishment status the more males the females attracted (5, 10 and 15, respectively).
"There was a nice positive correlation between female body condition and the number of males attracted," says Barry. "That's what you would expect in a normal non-deceptive system."
But Barry found the females in the 'very poor' group attracted the most males of all (25).
She says this was presumably due to the production of better quality or greater amounts of pheromones for deceptive purposes.
The findings support the Femme Fatale hypothesis, and the idea that a hungry female will spend resources on producing pheromone because it's worth the benefits she gets from deceiving the male.
The results are published today in the Royal Society journal Proceedings B.
A key difference between Barry's most recent study and earlier research was that it took into consideration research showing that a female mantis needs to have at least one egg to produce sex pheromones.
While previous studies had not considered this, Barry confirmed the presence of eggs in all the females by dissecting them at the end of the experiment.
Cannibalism in Pseudomantis albofimbriata begins before copulation, says Barry.
The first thing the female does is bite off the male's head and forelegs to disable him as quickly as possible.
But, says Barry, the male can still get his end in before he is completely eaten.
Because he has two brains — one in his head, and one in his abdomen — a headless male is able to bend the rest of his long body around to copulate.
Read more at Discovery News
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