How to have sex and survive

Researchers have discovered that even the gruesome and brutal lifestyle of the Evarcha culicivora, a blood gorging jumping spider indigenous to East Africa, can’t help but be tempted by that ‘big is beautiful’ mantra no matter what the costs. A study recently published in Ethology found that despite the inherent risk of sexual cannibalism, virgin females were attracted to bigger males when losing their virginity before opting for the safer smaller male as a longer term mate choice.

It is quite common for male spiders to fall victim to female sexual partners once they have mated as the female is more often than not bigger than her mate. In the case of E. culicivora, the gender roles and the size ranges of both sexes are different from the norm and this is important in understanding the evolution of their mate choice behaviour. Large males are more cannibalistic towards smaller females than vice versa.

Consequently, virgin females prefer larger males as mates, in spite of the increased risk of cannibalism, but once the females have mated they change tact and prefer smaller males. In contrast, males make the same choice regardless of whether they are virgins or not and prefer larger females as mates overall.