Plus-size problem

Large, long-tusked elephants tend to make the best fathers and dominate their mating grounds over the smaller guys. But zoologists from Oxford University have found that the average tusk size of Asian and African elephants has shrunk—in half, in the African case—since the mid-19th century. This evolution has occurred in a startlingly short 150-year time span, and the researchers believe it may be due to poaching and hunting of the larger elephants, who boast larger tusks. As larger elephants are killed, smaller, younger bulls have mating opportunities they wouldn’t typically have, resulting in a progeny of smaller-tusked elephants.