Animal suicide

Self destructive behavior has been observed in various species in the animal kingdom which some have likened to suicide.

"Suicide" has been observed in salmonella seeking to overcome competing bacteria by triggering an immune system response against them.[1] Suicidal defences by workers are also noted in a Brazilian ant Forelius pusillus where a small group of ants leaves the security of the nest after sealing the entrance from the outside each evening.[2]

Pea aphids, when threatened by a ladybug, can explode themselves, scattering and protecting their brethren and sometimes even killing the lady bug.[3] Some species of termites have soldiers that explode, covering their enemies with sticky goo.[4][5] There have been anecdotal reports of dogs, horses, and dolphins committing suicide, but with little conclusive evidence.[6] There has been little scientific study of animal suicide.[7]

References

  1. ^ Chang, Kenneth (August 25, 2008). In Salmonella Attack, Taking One for the Team. New York Times. http://www.nytimes.com/2008/08/26/science/26obsalm.html?ref=science 
  2. ^ Tofilski,Adam; Couvillon, MJ;Evison, SEF; Helantera, H; Robinson, EJH; Ratnieks, FLW (2008). "Preemptive Defensive Self-Sacrifice by Ant Workers" (PDF). The American Naturalist 172 (5): E239–E243. doi:10.1086/591688. PMID 18928332. http://www.cyf-kr.edu.pl/~rotofils/Tofilski_etal_2008.pdf. 
  3. ^ Larry O'Hanlon (Mar 10, 2010). Animal Suicide Sheds Light on Human Behavior. Discovery News. http://news.discovery.com/animals/animal-suicide-behavior.html 
  4. ^ Life In The Undergrowth. BBC. http://www.bbc.co.uk/pressoffice/pressreleases/stories/2005/10_october/20/life_horrors.shtml 
  5. ^ Bordereau, C; Robert, A.; Van Tuyen, V.; Peppuy, A. (August, 1997). "Suicidal defensive behaviour by frontal gland dehiscence in Globitermes sulphureus Haviland soldiers (Isoptera)". Insectes Sociaux (Birkhäuser Basel) 44 (3): 289. doi:10.1007/s000400050049. http://www.springerlink.com/content/m727aywa4mdf04ln/ 
  6. ^ Nobel, Justin (Mar. 19, 2010). Do Animals Commit Suicide? A Scientific Debate. Time. http://www.time.com/time/health/article/0,8599,1973486,00.html 
  7. ^ Stoff, David; Mann, J. John (1997). "Suicide Research". Annals of the New York Academy of Sciences (Annals of the New York Academy of Sciences) 836 (Neurobiology of Suicide, The : From the Bench to the Clinic): 1–11. doi:10.1111/j.1749-6632.1997.tb52352.x. http://www3.interscience.wiley.com/journal/120752899/abstract