Ethological isolation, Biology

Assignment Help:

Members belonging to different species refrain from mating because of the behavioural differences between them. Such behavioural differences usually centre around specific courtship patterns which the species have evolved. The behaviour patterns are more conspicuous in animals rather than in plants. And among animals, once again, the courtship behaviour is more pronounced among terrestrial and fresh water organisms than in marine forms. Mayr points out that in those forms where there is an elaborate courtship behaviour the interspecific hybrids are rare. Closely related species that do not have pair-binding courtship rituals do commonly give rise to hybrids. Mayr is of the opinion that in species where there is a courtship behaviour pattern, the "engagement" may be broken if the pairs do not belong to the same species, A detailed study of the courtship behaviour of six species of Drosophila showed that courtship and mating could be divided into six phases. If there is incompatibility at any one of these six phases, the potential mates break off and the courtship is discontinued. Under laboratory conditions, the interspecific crosses have not been successful and the courtship was terminated even in the first stage. What is more interesting here is that even to a trained observer differences in courtship behaviour exhibited by different species may appear to be trivial and insignificant. But the species recbgnise the specific signals and respond suitably. In certain other forms differences in courtship behaviour between species could be very pronounced, The courtship dances of the different species of Uca (shore crab) could be recognised from a distance. This is also true of mating dances of salamanders, turtles and birds.


Related Discussions:- Ethological isolation

What is crf annotation checklists, Question 1: Highlight the salient...

Question 1: Highlight the salient features of eTrials EDC. Explain briefly what is eTrials EDC Describe the salient features of eTrials EDC in comparison with other ED

Micro biology, explane the role of nitrogenase enzyme

explane the role of nitrogenase enzyme

Explain microbiology of vegetables, Q. Explain Microbiology of vegetables? ...

Q. Explain Microbiology of vegetables? Ans. All of us are well aware that vegetables are grown in soil, which, we already know, are a rnajor support system for the mi

Somatic and germline gene therapy, All the cells present in the body contai...

All the cells present in the body contain genes and an approach targeted to modulate the expression of genes is known as gene therapy. This novel approach has emerged by the end of

Important herbaria, Q. Important Herbaria? The herbarium is a place whe...

Q. Important Herbaria? The herbarium is a place where dried and mounted specimens are stored according to any recognised system of classification. Special attention is paid tow

Define procedure for gram staining of bacterial cultures, Define Procedure ...

Define Procedure for Gram Staining of Bacterial Cultures? Now carry out the exercise following the steps enumerated herewith: 1. Label the nutrient agar plates with the name

Structure of human testis, Structure of human testis: The male repro...

Structure of human testis: The male reproductive system consists of a pair of testis. Testis are male reproductive organs and produce (male gametes) sperms and also secrete

Explain fetal development, Explain Fetal Development? The medical profe...

Explain Fetal Development? The medical profession divides pregnancy into three-month stages called trimesters. At the end of the first trimester, the fetus is only about 5 cm l

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd