Baculovirus-induced climbing behavior, historically known as “Wipfelkrankheit” (tree top disease), has been attributed to the viral <i>egt</i> gene.

<p>Gypsy moth (<i>Lymantria dispar</i>) larvae that were infected with wild type <i>L. dispar</i> MNPV (LdMNPV) (A) demonstrated increased climbing behavior compared to a mutant of LdMNPV lacking the <i>egt</i> gene (B) <a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1003729#ppat.1003729-Hoover1" target="_blank">[8]</a>. This evolutionary adaptation is thought to aid in virus dispersal after death of the larvae, resulting in increased dispersal of occluded virus to the rest of the vegetation below.