Speciation, Biology

Assignment Help:

SPECIATION -

  • Origin of new species: An isolated population of a species independently develops different types of mutations.
  • The later accumulate in its gene pool. After several generations, the isolated population becomes genetically and reproductively different from others so as to constitute a new species.
  • The million of different species that exist today did not emerge by any single sequence of events but have come into existence by following types different paths of speciation.

1.       PHYLECTIC SPECIATION -

  • Darwin entitled his great book.
  • For Darwin, speciation was the simple, gradual accumulation of changes in a lineage throughout time, until the group was distinct enough to be considered a new species. This process is now called phyletic speciation.

2.       ALLOPATRIC SPECIATION -

  • It is considered as the most common type of speciation.
  • Allopatric speciation typically occurs when a physical barrier i. e., a mountain range, a river, or an oil pipeline, geographically separates a population from its parental population.
  • E.g., Different species of Darwin finches in the Galapagos Island.

3.       SYMPATRIC SPECIATION -

  • Sympatric speciation occurs in populations where individuals continue to live among one another, even though some type of biological difference, such as the time of the year when gonads mature, has divided the members into different reproductive groups.
  • The best accepted cases of sympatric speciation occur in plants as a result of polyploidy, an increase in the number of sets of chromosomes per cell occurs.

4.       PARAPATRIC SPECIATION -

  • Parapatric speciation is thought to occur in populations that lie adjacent to one another.
  • Gene pools diverge because the environment varies sufficiently in the different localities.
  • As a result, different traits are selected in each population.

Related Discussions:- Speciation

Interior of the left atrium - heart, The left atrium is a thin walled cavit...

The left atrium is a thin walled cavity. Most of the wall is smooth. Musculi pectinati are present only in the auricle of the atrium. The interatrial septum separates the cavity of

Define nutrition support in postoperative nutritional care, Define Nutritio...

Define Nutrition Support in Postoperative Nutritional Care? Aggressive nutritional support is important to avoid postoperative complications and mortality. Routine postoperativ

Determine majority of segregation errors in human patients, Which of the fo...

Which of the following defines why the vast majority of segregation errors in human patients include the two sex chromosomes (XXY, XO, XYY) or chromosome 21 (triple 21)? A. The

Infective endocarditis, Despite improvements in health care, the incidence ...

Despite improvements in health care, the incidence of infective endocarditis has not decreased over the past decades. Infective endocarditis is lethal if not aggressively treated w

How to measure a quality of water sample, various parameters which are used...

various parameters which are used in water quality measurement

Which responds to electrical signals, You have identified a protein in a ce...

You have identified a protein in a cell that you know that comes from the human body. With respect to that protein you have also determined that it allows sodium ions to go through

Determine the statement- the evolution of color vision, Based on your readi...

Based on your reading of the article entitled "The Evolution of Color Vision", which of the following is a false statement? A. Trichomatic vision is found in all male and femal

Primitive nervous system - nerve net, Primitive Nervous System - Nerve Net ...

Primitive Nervous System - Nerve Net A nervous system creates its appearance for the first time in the phylogeny among Cnidaria. In this group the nerve cells make an irregula

Determine nutritional requirements in hot environments, Determine Nutrition...

Determine Nutritional Requirements in Hot Environments? Hot environments may be of two types: dry hot, as in the case of deserts or hot and humid in tropical rain forests and c

Define altered glucose metabolism - nutrition during stress, Define Altered...

Define Altered Glucose Metabolism - Nutrition during Stress? Blood glucose levels are generally elevated in the infected patient but plasma insulin levels are normal or even hi

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