Where one species leads, another follows: interspecies processions in tropical caterpillars.

One sunny July morning on the Neotropical island of Trinidad, a group of caterpillars, hundreds strong, marched in head-to-tail procession up their host tree. Among them were two morphs: the majority, long-haired and black, and in smaller numbers, a more cryptic short-haired brown morph. Both proceeded up the tree trunk, thoroughly integrated, and indistinguishable from each other in their behavior. At the bifurcations of branches they split into smaller processions, and continued to the very tips of the branches.