Larvae of a parasitic fly evade predation by abandoning their hosts when they are in peril.

“A recently discovered fly, Endaphis fugitiva,
may be the first known parasitic insect that is able to escape a host
that is under attack from predators. When researchers injured the fly’s
host — called the banana aphid — or let brown lacewings attack the
aphids, the fly larvae broke out of the aphid’s body

“The ability of E. fugitiva larvae to shift
niches adaptively may help them to avoid being killed along with their
host, but it comes at the cost of having to devote resources to
detecting and avoiding threats, write Muratori and his co-authors. The
researchers speculate that the larvae detect their host’s imminent
demise either by sensing chemical cues, such as stress factors in the
aphid’s blood-like ‘haemolymph’, or by perceiving the mechanical
pressure of a predator’s attack on the aphid.” (Laursen 2010)

http://www.nature.com/news/2010/100113/full/news.2010.8.html
http://rspb.royalsocietypublishing.org/content/277/1687/1475.abstract

Last Updated August 18, 2016