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!
An interesting observation made by an American biologist H.C. Bumpus (1899) provides a good explanation for normalising selection. Bumpus collected some 136 injured house sparrows after a severe snow and sleet storm with high winds at Woods hole. Of these birds 64 died, resulting in two groups of sparrows, those that were killed by the storm and the ones that survived. Bumpus, made measurements of a number of randomly chosen traits such as wing length, wing span, tarsus length etc and found that those that were killed by the storm had measurements which fell at the ends of the bell shaped curve. In other words, birds which had either mean or close to the rnean measurements were the ones to survive. Normalising selection generally eliminates during a catastrophe or a stressful situation individuals whose traits vary markedly from the mean values. By way of interpreting Bumpus's observations, it could be said that the birds which were blown down easily by the winds had either their wings too long for their body weight and therefore presented a larger surface area or they had too short wings for their body size and therefore could not fly against strong winds. Prjor to the catastrophe the range of individual measurements was larger as compared to the range of measurements that survived the catastroihe. Every catastrophe may narrow down the variability of the population thereby weeding out suboptimal genotypes.
What is Sex-linked Traits in genetics? The X-chromosomes carry genes for traits other than sex characteristics. Morgan discovered these sex-linked traits while observing the in
characteristics of the Nematoda
what are viruses
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
identify structural modifiactions of the stomach and small intestine walls that enhance the digestive processes in these regions
Q. Can you explain about Ventriculography? Cardiac ventriculography is a diagnostic test, i.e., used to define the anatomy and function of the ventricles (left and right) and r
Yabapox Yabapox is a disease affecting mangabeys, rhesus, cynos, vervets, stumptails, and patas monkeys. It is caused by the Yaba-like disease virus (YLDV) and Yaba monkey tumor v
Define the Public Nutrition Public nutrition is concerned with improving nutrition in populations in both poor and industrialized countries, linking with continuity and public
Define Criteria for Assessment of Niacin Status? Niacin status can be monitored by daily urinary excretion of methylated metabolites, especially the ratio of the 2-pyridone to
What is Large Intestine in human biology? Food undigested in the small intestine is passed on by peristalsis into the large intestine, or colon. The intestine is composed of ci
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