SIGNALS USED BY INSECTS TO ATTRACT A MATE FOR SEXUAL REPRODUCTION

Insects have both male and female species that mate and reproduce sexually. Some insects reproduce by lying eggs while in some the egg hatches inside the female. During other seasons of the year the males are not available to mate with the female but species like aphids still reproduced.

Different insects use different strategies to to attract their mating partners. All these srategies mostly work only where they are reguired, meaning that if the signal is from the female butterfly it will be heard only by male butterflies.Semiochemicals are chemicals that causes interaction between organisms of different sexes. All these semiochemicals serve one purpose, to complete the life cycles of insects. "These chemicals are divided into allelochemicals and pheromones depending on the nature of interactions because the interaction can be either interspecific or intraspecific"(1).

"Allelochemicals are those chemicals that are important to individuals of a species that are different from the source species. These chemicals are also subdivided into different groups depending on whether the respond of the receiver is comfortable with the emitter not the receiver or the chemical is favourable with the receiver not the emitter or is favourable to both emitter and the receiver. Both allelochemicals and pheromones it is always useful to refer to chemicals as arrestants, attractants, repellents, deterrents, stimulants or other descriptive terms. These terms can indicate what behaviour is involved in the response such as a feeding stimulant or flight arrestant. Pheromones are released by a certain species with the effect of having the attraction to the same kind of species" (1).

Insects have different ways they use to attract each other like in the case of the moths. "The female moths have scent glands on the abdomen that secrete pheromones. These chemicals are secreted to attract the male moth. The male moth can detect these chemicals at a distance of four to eleven kilometres. Sometimes the males secrete pheromone just to induce the females so that they mate. Insects like butterflies use colour and movement. The males will be attracted by the coloured imitations of females and in the same time they will be chasing the other male away. Male flies also form a compact swarms that attracts the female" (4).

Sound is also used as a way to attract each other sexually. "The male mosquitoes are attracted to the note or sound produced by the wing vibration of the wing. Female grasshoppers, crickets and cicadas are attracted by the sound produced by their males. Crickets use the burrows to resonate the sound, the cicadas use their large empty space in their abdomen and the substrate vibration helps the leafhoppers to communicate"(4). It is very interesting to see how clever insects are. Especially looking at the different ways the male insects use to protect thier sperms. Some protect them by guarding the female everytime. Some have some chemicals which they put on the female so that she does not mate again until she give birth. Other males use the scoop to sweep other sperms away before they mate.

Reference

1. Nordlund, D. A. 1981. Semiochemicals their role in pest control. [Internet] 2006 May 08; 15:05 UTC [Cited 2006 May 08] Available From: http://ipmworld.umn.edu/chapters/flint.htm

2. Wikipedia contributors. Insects [Internet] Wikipedia, The free encyclopedia; 2006 May 08; 10:23 UTC [cited 2006 05 08] Available from: http://www.ivyhall.district96.k12.il.us/4th/KKhp/1insects/buginfo.html

3. Wikipedia contributors. Neuroendocrine [Internet] Wikipedia, The free encyclopedia; 2006 May 08; 11:15 UTC [cited 2006-05-08] Available From:
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7186527&dopt=Abstract

4. Wikipedia contributors. Reproduction [Internet] Wikipedia, The free encyclopedia; 2006 May 08; 14:35 UTC [Cited 2006 May 08] Available From: http://bugs.bio.usyd.edu.au/Entomology/InternalAnatomy/reproduction.html

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