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.
Q. What is the molecule that donates hydrogen for photosynthesis, in sulfur photosynthetic bacteria? In sulfur photosynthetic bacteria the substance that donates hydrogen is hy
Q. What are the Symptoms and Signs of pericardial effusion? Asymptomatic: Slowly accumulating small to moderate pericardial effusion may not cause significant elevation of intr
In the lack of tryptophan shown in the figure, a trp repressor protein encoded by a split operon, trpR that is synthesized and forms a dimer. Furthermore, this is inactive and so
biting mechanism in snakes
Explain about the Invert sugar? Invert sugar is sucrose, which can be hydrolysed to split the disaccharide into its component sugars, fructose and glucose. It is known as inver
Formation of New Membranes Divisions of the egg or blastomeres raise the total surface area of the two daughter cells to be covered via membrane at every cleavage. The parent
Explain the Effect of Deficiency of Vitamin E? Fortunately, vitamin E deficiency in human is extremely rare. This may probably be due to its wide occurrence. in natural foods a
Cleavage - Metazoa The unicellular zygote begins cell division (cleavage). First, the single cell divides forming two cells, these redivide further to form four, then eight ce
give an example invertebrate phylum/phyla for protoplasmic grade organization
Operative requirements for stage i surgery Although Implant placement under general anesthesia must be done in an operating theatre with complete resources, most implant surger
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