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

Altered fat metabolism - metabolic response to injury, Altered Fat Metaboli...

Altered Fat Metabolism - Metabolic Response to Injury? The stored fat deposiis are mobilized and oxidized at a high rate in order to support hyper metabolism and increased gluc

What do you understand by term - acanthus, What do you understand by term -...

What do you understand by term - acanthus The egg and larval phase of an acanthocephalan which passes from the female parasite to the feces of host.

Skin., what are the main functions of basal (Malpighian)layer?

what are the main functions of basal (Malpighian)layer?

Determine the blood plasma levels of glucose, Which of the following serves...

Which of the following serves as an actuating signal, or as part of an actuating signal, in a negative feedback system? A. Blood plasma levels of Glucose. B. Blood plasma le

Agama lizard, excretory system in agama lizard

excretory system in agama lizard

Explain the expanding frontiers of nutrition, Explain the Expanding Frontie...

Explain the Expanding Frontiers of Nutrition? While the essential nutrients mentioned in Table are indispensable and our diets need to provide them all in adequate quantities,

Protein requirement during congestive cardiac failure, Q. Protein Requireme...

Q. Protein Requirement during congestive cardiac failure? Protein: The protein requirements remain the &me as healthy adult men and women, About 0.8 - lg of protein per kg

Pachytene, Pachytene: The pairing of homologous chromosomes is comp...

Pachytene: The pairing of homologous chromosomes is completed. Chromosomes become more and more thick. Each bivalent has four chromatids , which wrap around each o

Explain process of selection of taxonomic characters, Explain process of Se...

Explain process of Selection of taxonomic characters Selection of taxonomic characters Eventually classification systems may be based almost entirely on direct study of th

Bioclimatology effect of climate on distribution of organism, Bioclimatolog...

Bioclimatology: This is the study of effect of climate on distribution of organisms. Bioclimatology is the inter-disciplinary field of science which studies the interactions betwe

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