Researchers at the University of Derby have declared the tuberous bush-cricket, whose, ahem, testes make up 14% of its body mass to have the biggest ball of them all.
From Science Daily:
Yet the research team also discovered that large testes did not necessarily relate to a larger amount of sperm produced — which goes against traditional thinking in the science world. […]
Dr [James] Gilbert said: “Traditionally it has been pretty safe to assume that when females are promiscuous, males use monstrously-sized testicles to deliver huge numbers of sperm to swamp the competition — even in primates. Our study shows that we have to rethink this assumption. It looks as though the testes may be that big simply to allow males to mate repeatedly without their sperm reserves being exhausted.”
If you have balls that big, then chances are good you’re going to be surrounded by a lot of bush. See what I did there?