Sexual selection, Biology

Assignment Help:

In this section you will be introduced to a variant of Darwinian concept of natural selection which he termed sexual selection. You may have observed very distinct and striking differences in appearance between opposite sexes of various animals groups, more prominently in birds and mammals. When differences in appearance occur between sexes, the animals are said to exhibit sexual dimorphism, the phrase simply meaning that themales and females are not uniform in appearance, but present two different forms. In general the males of the species are strikingly  different from females although there may be exceptions to this rule. The male of the species may be more aggressive, brilliantly coloured or possess elaborate combs or bright plumage or extensive horns or ornamental hooks, tusks, spurs etc. Why are the male members different from the females? Is it not that the possession of such extra structures easily identify them to the enemies and make them more susceptible to their attack? Can these characters therefore be regarded as disadvantageous or ill-adaptations? If that be the case, is not the theory of natural selection contradicted?

As an answer to these questions, Darwin proposed the theory of sexual selection. According to the theory, the females of the species select their males and therefore a male which is more attractive or stronger than the other members of its sex has better chances of mating and leaving behind its offspring. In males there'will be a constant evolution of such characters which are attractive to their female counterparts. Sexual selection can be regarded as competition among the members belonging to a sex to win the members of. the opposite sex.


Related Discussions:- Sexual selection

Integumentary system - various glands, OTHE R GLANDS - (i) Mammary gl...

OTHE R GLANDS - (i) Mammary glands - Study of mammary gland is mastology. Modified sweat gland. 4-5 pairs in rabbit. 1 pair in human. In opposum 25 pairs (max.).

Define peri-implantitis, What is peri-implantitis? Peri-implantitis as ...

What is peri-implantitis? Peri-implantitis as defined by Meffert is the progressive loss of peri-implant bone as well as soft tissue inflammatory changes. Bacterial invasion of

Explain disease dengue, Dengue Dengue fever is a viral disease transmi...

Dengue Dengue fever is a viral disease transmitted by mosquito bites that occurs worldwide in tropical and subtropical areas. Major epidemics have occurred in recent years in

Can you explain bacillus cereus poisoning, Q. Can you explain Bacillus Cere...

Q. Can you explain Bacillus Cereus Poisoning? Ans. Bacillus cereus poisoning is caused by the organism which is a large (3-5 pm long .and 1-4 pm wide), gram po%tive,

Explain about post-operative pain, Post-operative pain  There is some d...

Post-operative pain  There is some discomfort for about 24-48 hours. Persistent pain for a longer duration, with swelling, may indicate possible infection around the implant an

Total darkness and pea seedlings grown in the light, What differences would...

What differences would you expect to see among pea seedlings grown for 10 days in total darkness and pea seedlings grown in the light for the similar period of time?   The s

Acute glomerulonephritis - disorder of glomerulus, Acute Glomerulonephritis...

Acute Glomerulonephritis   If you review the anatomy of urinary system you will recall that nephron is the working unit of kidney and its number  exists  in millions. Within  t

What is genomics , We are living in an unprecedented age of biological ...

We are living in an unprecedented age of biological discovery and the application of biological knowledge.   Programmed DNA sequencing delivered, in the year of  2001 over the 2.6

Biological responses controlled by phytochrome, Biological Responses Contro...

Biological Responses Controlled by Phytochrome Phytochrome responses are those which are controlled reversibly by red and far-red light. These can be broadly categorised as:

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