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.
COMMON DISEASE OF CATTLE & BUFFALOES - 1 . Anthrax - Its symptoms are high temp, painless & warmthless swellings on different body parts. Bloody discharge from na
Absorption of proteins in infants In infants, permeability of the intestine appears to be greater than in later life, and some large protein molecules such as antibodie
Endosperm - Pollen Biology The examination of live material of j. montana reveals that the division of the primary endosperm nucleus is transverse, followed by the laying down
how vagina is inserted in cock
what features are in a epithelial cell
State about membrane-spanning molecule Neuron A is a healthy neuron with all the usual ion channels and with all the usual intracellular and extracellular distributions of ion
Protozoans are microscopic in size however some are large enough to be seen with naked eye. Microscopic organisms such as these have numerous advantages, one of which is that they
A woman who is heterozygous for a particular X-linked recessive trait marries a phenotypically normal man. What percentage of their sons will show the recessive phenotype?
What is the meaning of Visuoperceptive disorders It relates to the way in which brain damage impairs people's ability to adapt to the visual world and the concepts used to trea
Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4
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