Pea aphid youngsters use piggyback rides to escape a crisis
Hitching a ride on reluctant adults helps babies survive after fleeing a grazing animal
By Susan Milius
First it’s mammal bad breath. Then it’s babies pestering for piggyback rides. A near-death experience is tough on pea aphids.
When warm, moist breath signals that some cow or other giant is about to chomp into foliage, tiny green aphids feeding on that foliage drop toward the ground by the hundreds (SN Online: 8/10/10). “It literally rains aphids,” says ecologist Moshe Gish, who in 2010 described the breath cue.
Now Gish and Moshe Inbar, both at the University of Haifa in Israel, describe what pea aphids (Acyrthosiphon pisum) do after they hit the ground. There’s “a climbing frenzy,” Gish says. “Frantic” newborns scramble onto adults for a piggyback ride to safety.