Male spiders clamber towards females along silk bridges
By James Dacey
In the world of male spiders vying for the affection of their female counterparts, it seems that small is often better.
That’s according to a group of biologists who have come up with an interesting explanation of why male vegetation-inhabiting spiders with smaller bodies can find more opportunities to mate with females.
It is related to the agility of the male spiders. When they spy a potential mate, the males allow a strand of silk to fly on the wind towards a target close to the female. They then rush along this silky rope as fast as they can in a manoeuvre that would make Spider-Man proud.
A team led by Guadaloupe Corcobado, of the Spanish National Research Council’s Arid Zones Research Station in Almeria, has studied this “bridging” tactic in detail inside a wind tunnel. They find that the smaller, lighter males are significantly more adept at the procedure, which boosts their mating opportunities.
They describe their “gravity hypothesis” in a new paper in BMC Evolutionary Biology.