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

Chemicals responsible for imparting the sweetness, The chemicals responsibl...

The chemicals responsible for imparting the sweetness, classic salt taste and bitter and sour taste are summarized herewith.  A. Sweet Taste Sweetness is one of the most importa

Epidemiology, 9. A simple and inexpensive screening method has been develop...

9. A simple and inexpensive screening method has been developed to identify individuals with HIV infection at routine medical check-ups. To study the sensitivity and specificity, t

Draw format where carbon double bonded to an oxygen atom, How do you draw i...

How do you draw in organic chemistry format a carbon double bonded to an oxygen atom when this carbon is the first carbon on a carbon skeleton of a molecule?

What are the hormones that release of the female gamete, What are the hormo...

What are the hormones that promote the release of the female gamete from the follicle and at which day of the menstrual cycle does this phenomenon happen? What is this event called

Explain therapy of specific lipid disorders, Q. Explain Therapy of Specific...

Q. Explain Therapy of Specific Lipid Disorders? a) Very high LDL levels usually result from inherited disorders of lipoprotein metabolism and carry a high risk of premature at

What are the luria''s methods and theories, What are the Luria's methods an...

What are the Luria's methods and theories Adhering to our theory that the Luria Nebraska bears little resemblance to Luria's methods and theories, there seems little point in i

How do antibody-based tests detect how hiv infection work, Q. How do antibo...

Q. How do antibody-based tests detect how HIV infection works? Subsequent to the infection by the HIV the immune system begins the production of antibodies (primary immune resp

Explain direct microscopic count - measurement of microbes, Explain Direct ...

Explain Direct Microscopic Count - Measurement of Microbes? The most obvious way to determine microbial number is through direct counting under a microscope. In this method, a

Neuroglia - organisation of nervous system, Neuroglia - Organisation of Ner...

Neuroglia - Organisation of Nervous System We may refer neuroglia as the connective tissue of the nervous system. It involves all elements of the nervous system other than ne

Acupunture-osteopathy-herbal therapy, Alternative Therapies Assignment 1...

Alternative Therapies Assignment 1. A. Acupunture, B.  Osteopathy, C.  Herbal therapy For each one of alternative therapies above, answers the three questions below! 1. Th

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