Cited research: Anim. Behav. doi:10.1016/j.anbehav.2010.03.002 (2010)

Generalist predators can feed on a variety of organisms to ensure a balanced diet, but specialists that prey on only one animal do not have this luxury. Stano Pekár of Masaryk University in the Czech Republic and his team looked at how ant-eating Zodarion rubidum spiders (pictured) cope with this dietary limitation.

They found that spiders fed only ant foreparts grew faster and survived longer than those consuming whole ants. Both fared better than those eating only ant gasters (hind parts).When presented with large whole ants, the spiders fed longer on the protein-rich foreparts than on the lipid-rich gasters. This shows how feeding behaviour might allow specialist predators to balance their nutrient intake.

Credit: S. PEKAR