Bacteria in the guts are good for you?

Introduction:

Termites have roamed the earth since the time of the dinosaur yet most species have not yet developed a way to digest cellulose on their own [1]. Millions of years ago, termites learned that a bacterium in their gut could help them break down the cellulose and plant fibers that they eat [2]. Since then termites and Trichonympha have lived in a symbiotic relationship with one another. Most ever species of termites share

a relationship with the bacterium Trichonmympha and because termites are found worldwide, and mostly in tropical areas, so is their bacterium [3].

The life cycle of a termite is depended on two things: the species and the environment. Some species live longer than others and some environments support termite life better than others. Warmer climates allow termites to live a longer life [4]. A queen termite in some species can live for a decade or more while a worker or solider termite has a life span of one to five years. A termite goes through three stages of development. Eggs hatch to reveal nymphs from there two different types of termites develop: the worker

termite and the solider termite. Both types continue to molt and form into the adult termite. Due to termites having incomplete metamorphosis, both worker and solider termites grow wings. This stage with wings is called the alates stage. The termites continue to grow and they shed their wings. From there a king and a queen termite mate and the female lays more eggs to continue the cycle [5].

Termite nymphs are not born with the bacterium Trichonympha but rather they must be infected with it from one of the older termites. Every time a termite molts it must infected again in order the termite to survive [6].

Description of Relationship:

Most species of termites and the bacterium Trichonympha, from the genus parabasalian, have a mutualistic relationship, meaning that each benefits from the other. The termites are placed in a category of eusocial insect meaning that they raise their young as a group [7]. As a nymph, these termites are white in color and are thus referred to as “white ant” [2]. The colonies of termites consist of two different forms of termites. The worker termite is blind, wingless and sterile. It is unpigmented, soft, and works in dark moist areas. Worker termites are needed to build nests, get good, and feed the solider termites. The solider termites are every bit the same in appearance as worker termites except solider termites have a hard cuticles rather than soft ones and they have a brown head rather than a white one. Solider termites also have large mandibles that allow them to defend the colony against intruders [8]. King and queen termites have wings that are twice the size of their bodies and their main job in the colony is to reproduce [9].

Trichonympha inside the gut of the termite helps the termite digest cellulose and plant fibers that the termite could not digest on its own. This adaptation has allowed termites to survive for millions of years while allowing the bacterium to continue developing. The bacterium inside the termite engulfs the eaten wood or plant substances and uses a bacterium of its own to break it down.

Cost/Benefit Analysis:

Termite

• Cost: must be infected with bacterium in order to survive

• Benefit: bacterium helps termite get its food digested

Trichonympha

• Cost: they have to live inside termites otherwise they cannot make cellulose for their own self
• Benefit: termites provide food and shelter [10].

References:

[1] http://www.pestworldforkids.org/termites.html

[2] http://en.wikipedia.org/wiki/Trichonympha

[3] http://www.springerlink.com/content/p439l941w617627q/

[4] http://www.termiteweb.com/the-typical-termite-life-cycle/

[5] http://termite-control-protection.blogspot.com/2010/09/subterranean-termite-reticulitermis.html

[6] http://www.mrcroft.com/notes/ecology/Termite%20Symbiosis%20Lab.pdf

[7] http://en.wikipedia.org/wiki/Termite#Diet

[8] http://www.fzi.uni-freiburg.de/InsectPestKey-long%20version/termit2.htm

[9] http://www.allmaxpestcontrol.com/Termite.html

[10] http://wiki.answers.com/Q/Why_do_termites_need_bacteria