Assassin Bug Deception (Aggressive mimicry)

While looking for articles in the popular media to present to the Biology 101 students I stumbled upon an interesting article about a species of assassin bug (Stenolemus bituberus) that tricks spiders in order to capture them. This behavior is known as "aggressive mimicry". I also managed to find the scientific article that the media article was based off of. The species that is the focus of the study is pictured below.

From the popular media article:
"A new study has just revealed the bugs' devious and deadly tactics. Like nightmarish bass players, assassin bugs pluck spider silk in webs, mimicking the movements of exhausted, stuck prey. When the hungry spider eases in for what it thinks is a sure meal, the assassin bug taps the spider, and then grabs, stabs and eats it." This seems to be a fairly accurate description of what is stated in the scientific article.

From the scientific article:
"The vibrations generated by bugs showed clear structural similarities to those generated by prey struggling in the web."

This particular species of assassin bug (S. bituberus) spends nearly its entire life in spider webs and preys upon a variety of spiders. This is dangerous prey for an insect, and counterattacks by the spiders are often observed resulting in the death of the assassin bug.

Other than being an intersting topic, the other reason I am bringing this article up is to show how the popular media may confuse readers about the significance of findings. After describing the study the popular media article stated: "Studies on the behavior and biology of certain species of assassin bugs, such as those from South America, could help to wipe out Chagas disease, a parasitic infection."

It can be very confusing for readers when reporters make a links to other topics. There are 1000's species of assassin bugs.The particular species that spreads Chagas disease is not the one that preys upon spiders. Chagas disease is spread by the "kissing bug" from the subfamily Triatominae. The picture below shows an example of a kissing bug.
The media will often seek a connection to humans in order to make the topic more interesting to readers. The type of assassin bug that spreads Chagas disease looks, and acts very different from the species described in the study, and is not even mentioned within the scientific article. The media article makes it seem like studying the behavior of deceptive assassin bugs can help wipe out Chagas disease. I do not think that this is a very good connection.

The media article also mentions termite killer assassin bugs, "...But some assassin bug species, such as those nicknamed "termite eaters," can benefit humans. These cunning pest-killers use dead termites to trick live ones into approaching them. This talent could make these assassin bugs a handy, natural form of pest control". Even though it as not mentioned in the scientific article, This statement actually relates to the overall topic of deception! This assassin bug (Salyavata variegata) is pictured below:Termites will often eat the carcasses of other termites for more protien, and to keep the nest clean. Salyavata variegata takes advantage of this behavior by using termite carcasses as bait.


Photo credit: Jim Kramer (bugguide.net); http://www.scielo.br/scielo.php?pid=S1519-566X2003000100001&script=sci_arttext; www.brisbaneinsects http://.com/brisbane_assinsinbugs/TermiteAssassin.htm
Link to the media article: http://www.msnbc.msn.com/id/39879727/ns/technology_and_science-science/
Citation for the scientific article: Wignall, A. E. and P. W. Taylor. 2010. Assassin bug uses aggressive mimicry to lure spider prey. Proceedings of the Royal Society B: Biological Sciences