Variability in populations, Biology

Assignment Help:

Variability refers to the differences in heritable traits exhibited by the individuals of a species. One of the major contributions of Darwin to the study of evolution was his book of 1868, 'The Variation of Animals and Plants under Doxnestication'. Danyin pointed out that populations of living organisms are not composed of identical individuals.

It is indeed true that even monozygotic twins may express differences between them. Onecan cite a number of examples to indicate the differences in different traits in a population. Certain traits are continuously varying such as the height or colour, and certain other traits exhibit two or a few distinct, different categories of individuals with no intermediates. For example in human population, there are P'C tasters and non-tasters; individuals with blood groups A or B or AB or 0, individuals with black or brown or blue eyes, individuals suffering from sickle cell anaemia and individuals who are normal, so on and so forth. Sweet peas may have either red flowers or white ones; Drosophila may have normal or vestigial wings, red or white eyes etc. Essentially the major source of variability in organisms is the genetic variability caused by mutations of all kinds and genetic recombination. Also the subtle effects of environment add another dimension to the variability of traits in natural populations. An oft cited example is the differences exhibited in a number of traits of monozygotic quadruplets of a nine-banded armadillo.


Related Discussions:- Variability in populations

The basics of dna cloning, There  are a broad  range  of various  process  ...

There  are a broad  range  of various  process  for cloning  DNA  into  either viral  or plasmid vectors  but the basic  scheme  of events  is frequently  same.  To clone into a pl

Which term describes study of animal behaviour, Which of the below terms de...

Which of the below terms describes study of animal behavior based on comparisons, observation of patterns, and consideration of environmental adaptations? Is it: a) Ethology (p

Define the clinical success for the root canal treatment, Define the Clinic...

Define the Clinical success for the Root Canal Treatment a) Absence of pain and swelling. b) Disappearance of sinus tract. c) No evidence of soft tissue destruction, incl

Process of asexual reproduction, What name is given to the population of ge...

What name is given to the population of genetically identical offspring which result from a process of asexual (vegetative) reproduction?   The population of genetically id

Explain the relaxing incision - endodontic surgery, Explain the Relaxing In...

Explain the Relaxing Incision - Endodontic Surgery A short vertical incision placed in the marginal and attached gingival, and located at the extent of the Horizontal incision

What type of feedback loop is, The client was admitted to the hospital with...

The client was admitted to the hospital with hypertension (high blood pressure). The development of arteriosclerosis (plaque buildup in the arteries) has increased peripheral resis

Pathophysiology and assessment of purpura, Pathophysiolog y   Normal...

Pathophysiolog y   Normally the platelets are formed from megakaryocytes (stem cells) in the.  bone marrow. These cells mature, fragment and are released in  the blood strea

How mineral salts participate in osmotic regulation, Q. How mineral salts p...

Q. How mineral salts participate in osmotic regulation? Osmotic pressure depends not on the nature of such particles and on the number of particles dissolved in a solution. Min

Oestrous cycle, OESTROU S CYCLE - Also known as heat period. Common in...

OESTROU S CYCLE - Also known as heat period. Common in rabbit, cat, dog, sheeps. In this period desire for copulation occur. Possibility of fertilization is 100%.

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd