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. Write the definition of communication? Communication is "a process of transmitting ideas, information, attitudes (images which we have formulated for ourselves) by the use o
sanguivarous mode of feeding in annelida
Conduits Figure: Venous Conduits Reversed saphenous vein was the first conduit used for CABG. 'It is usually harvested from the leg starting above the ankle going up
What is the type of cell division that allows sexual reproduction? What is gametogenesis? Meiosis is the type of cell division that permits sexual reproduction since it decreas
In Dental Traumatology Traumatic injuries in young kids (8 to 14 years old male > female) are commonly nowadays. Dental traumatic injuries are mostly in anterior teeth
The fragility of erythrocytes The fragility of erythrocytes is impaired in the absence of NADPH generation due to the deficiency of glucose-6-phosphate dehydrogenase thereby ca
Q. Mechanical means of instrument cleaning? Using mechanical means of instrument cleaning rather than hand scrubbing should minimize handling of instruments. If procedures are
Determine number of sucrose molecules in the solution When a solid is dissolved in a volatile solvent the vapour pressure of the solution is less than the vapour pressure of th
Q. What treatment should be used for constrictive pericarditis? Medical Treatment 1) Judicious use of diuretics to alleviate systemic congestion. This may be enough in s
Q. What is an example of intraspecific competition? The Intraspecific competition occurs in practically all species, for instance, the competition of humans for a job.
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