Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
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.
Define Aerobic Exercise or Aerobic Energy System? To produce necessary energy, the body uses an aerobic pathway and an anaerobic pathway. Exercise that relies heavily on oxygen
What is inflammation? Inflammation is the initial response of the unspecific defense system versus aggressions against the body (the aggressions might be caused by infectious p
ISOMERISM AND STERIOISOMERISM IN HEXOSE SUGERS
Why is a balanced frequency of different alleles of a gene in a population more useful for the survival of that population facing environmental changes? For the trait condition
MOSAI C THOERY - It was given by W. Roux. He studied the development of frog's egg. He destroyed one cells by a hot needle out of 2-cells formed as a result of first cleava
In the fruit fly Drosophila, a rudimentary wing called "vestigial" and dark body color called "ebony" are inherited at independent loci and are recessive to their dominant wild-typ
1. Write general characters of phylum mollusca and classify it upto classes, giving at least two examples of each class.
Explain the Sensory Respiratory center - Feature of Medulla Respiratory center: The center for regulating rate and depth of respiration is present in the medulla. Here, nerve i
Members belonging to the scientific community fear the misuse of this therapy leading to dangerous consequences. People may try to insert the desired gene, for example, the gene f
Explain the Principle of Development The final guiding principle is that assessment involves the measure of change, or development, across multiple levels of analysis. Developm
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd