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.
Mr. Smith read that cholesterol was bad for his health so he eliminated all foods and food products containing this molecule. He later found that his cholesterol level dropped only
The biosphere is composed of all living organism. This sphere includes all the microorganism, plants and animals of earth. In fact biosphere involves interaction of living beings w
How you can Repair Ventricular Aneurysm with a patch? Repair of Ventricular Aneurysm with a patch : Originally described by Cooley, as endoaneurysmorra
Silviculture: It concerned with the cultivation of timber yielding plants. Silviculture is the way of controlling the growth, establishment, composition, health or quality of fore
The biomass available for consumption by the herbivores and the decomposers is called : 1. Net primary productivity 2. Secondary productivity 3. Standing crop 4. Gross
When toxic substances enter lakes, streams, rivers, oceans and other water bodies, they get dissolved or lie suspended in water. This causes pollution of water bodies, which degrad
Why the rate of photosynthesis does increases, peak, and then reduces as temperature increases? Increasing the temperature initially accelerates the many chemical reactions in
Body Cavity and Coelom - Metazoa Vacuoles, spaces, lacunae and cavities have been of importance in all organisms, may it a be plant or animal. All animals have cavities. The c
The first step of the purification of an integral membrane protein is to disrupt its interactions with other integral proteins and the lipids in the membrane. This is commonly ach
Describe in detail about the unicellular eukaryotes Animal cel1.s and many types of unicellular eukaryotes contain centrioles, which are cylindrical in structure, about 0.15 m
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