Mechanical isolation, Biology

In certain instances differences in the morphology of genitalia between species make it impossible for normal mating to occur, and sympatric species tend to remain isolated. When there is no correspondence between the male and female external genitalia for copulation to occur, the members belonging to different species are reprod;ctively isolated. When interspecific crosses occur between individuals having no exact correspondence in their genitalia, it resulted in the death of copulating pairs. Isects and snails are usually quoted as examples of such fatal ratings which occur "due to mechanical differences in their genitalia. It must alao be stated that differences in cogulatory organs, in many instances, have not proved to be a barrier for ihterbreeding. Breeding between dogs belonging to different races is an often cited example.

Mechanical isolation appears to play a more important role in the speciation of plants. Since many plants are aided by insects and birds in cross pollination, a morphological compatibility is required between the plants and the pollinating agents. Further, queen bees with their long mouth parts pollinate the nector producing species of Pedicularis and the other species of the plants are pollinated sternotribically or nototribically.

Posted Date: 4/5/2013 5:48:24 AM | Location : United States







Related Discussions:- Mechanical isolation, Assignment Help, Ask Question on Mechanical isolation, Get Answer, Expert's Help, Mechanical isolation Discussions

Write discussion on Mechanical isolation
Your posts are moderated
Related Questions
Define the lens transparency in metabolism of lens. Lens Transparency: a. Transparency depends on avoidance of large transitions of refractory index. This is in other wor

What is the need of Monitoring and Surveillance? Monitoring, we know, is the act of observing something and sometimes keeping a .record of it while surveillance is a repeated s

physical properties of protoplasm

Q. Explain about Non ionising radiation? Non ionising radiation include infrared and UV rays. Lethal effect is through generation of heat and DNA damage. Penetration is low but

GER M LAYER THEORY - Proposed by Pander, studied chick embryo development. Coined the term ectoderm, mesoderm & endoderm.

#quesWhat benefits can commensalism offer to a species..

BIO GEOGRAPHICAL EVIDENCE- The patterns of distribution of animals and plants in different parts of the globe are termed as biogeography. It is believed that around carbo

Septa prevent oxygenated and deoxygenated blood. Give reason

Systemic embolization occurs in 22 per cent to 50 per cent of cases of IE. Emboli often involve major arterial beds, including lungs, coronary arteries, spleen, bowel, and extremit

SKIN CANCER: CAUSES AND TREATMENT PURPOSE: The objective of this assignment is to make you aware of the structure and function of your skin, what are the dangers that your skin ma