Biology 342 Fall 2012
Emily Agan, Christina Barrett
Phylogeny of the Feeding Behavior of A. luminosa
When discussing the behavior of Arachnocampa luminosa, one important question that should be asked is “How did these complex and fascinating behaviors arise?”
In order to address this fundamental question, other questions must also be asked, including
In what order did each individual aspect of the feeding behavior come to be?
While there are many other types of luminescent insects (fireflies), or types with traps or lures (spiders), or carnivorous kinds (praying mantises), the convergence of all of these patterns into one species begs the question “How did all of these behaviors occur in one insect?”
The firefly is an example of an insect that uses its bioluminescence for sexual selection, without any physical snares to lure in their prey. Spiders lack bioluminescence, but utilize elaborate webs to trap insects and eat them. This elegant praying mantis is an example of a carnivorous insect that lacks both webs and lures. Sourced from Firefly.org, Camillo Posada, and Wikipedia.
What are A. luminosa's closest relatives?
Arachnocampa luminosa has eight other members of its genus. These include:
How does the behavior of these relatives resemble A. luminosa's behavior?
All have luminescent larvae, which utilize snares. The genus Arachnocampa is a member of the family Mycetophilidae, or small flies which include fungus gnats. Members of this family usually live in moist areas. Many insects in Mycetophilidae display bioluminescence. Mycetophilidae is in turn a member of the order Diptera, or flies with two wings (Pugsley, 2008).