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

What is the dissociation and double dissociations, Dissociation and double ...

Dissociation and double dissociations Neuropsychologists typically try to design studies that provide evidence of the differential performance of brain damaged and control subj

Agro industrial-female reproductive disorders, Heifers As efficient reprod...

Heifers As efficient reproductive performance is essential for economic livestock production, the female calves must grow rapidly to attain sexual maturity, ovulate and be mated b

Marking regulations of honey, Q. Marking regulations of honey? The mar...

Q. Marking regulations of honey? The marking regulations indicate that each container of honey shall be suitably marked so as to give suitable information as follows: a) N

What are the two groups of defense mechanisms of the body, What are the two...

What are the two groups of defense mechanisms of the body against foreign or harmful agents? What is the difference between them? The body has many defense mechanisms against f

Types of stem cells-pulp tissue revascularization, Embryonic stem cells: c...

Embryonic stem cells: can differentiate into all cell types of the specialized embryonic tissues when given sufficient and necessary stimulation for a specific cell type, e.g. Plu

Poop, Where does poop come from?

Where does poop come from?

Nutrition, Why is holophytic nutrition a mode of autotrophic nutrition

Why is holophytic nutrition a mode of autotrophic nutrition

What is the cytoskeleton, Q What is the cytoskeleton? What are its major co...

Q What is the cytoskeleton? What are its major constituents in animal cells? Cytoskeleton is the cytoplasmic structure that supports the cell, keeps its fixates and shape and m

Explain deficiency diseases due to vitamin c, Explain Deficiency diseases d...

Explain Deficiency diseases due to vitamin C? Vitamin C deficiency in human's results in the disease called scurvy, whose symptoms include hemorrhaging (especially in the gums)

Describe what happens during activation of the lac operon, Describe what ha...

Describe what happens during activation of the lac operon. Lactose binds to the repressor protein, which causes the repressor protein to be released from the operator site. 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