Speciation, Biology

Assignment Help:

Ernst Mayr, for whom, species and species problem have been the main concern of research, points out that speciation, the multiplication of species, that is division of one parent species into several daughter species is one process responsible for the evolutionary diversity of organic world. Darwin no where in his book Origin of Species defined the word species precisely although he interpreted speciation in terrns of reproductive isolation (Darwin again did not use the term reproductive isolation in his book.) Darwin did en~phasise that occupation of an unique ecological niche by each species could be a major characteristic of speciation. In this unit we shall briefly analyse the species concept laying emphasis on biological species and discuss in detail different types of mechanisms of speciation. Further we shall briefly look into how isolation brings about genetic repatterning and proceed to discuss the mechanisms of isolation with well chosen examples. As an illustration of how isolating mechanisms develop gradually, we shall explain the concept of ring species - the evolution of distinct new species. Finally there will also be a discussion on a phenomenon called genetic drift which however has no causal connection with speciation process but explains that in peripheral isolates gene frequencies drift due smapling error.


Related Discussions:- Speciation

Lysosomes, Lysosomes Lysosomes are small vesicles which are bounded ...

Lysosomes Lysosomes are small vesicles which are bounded by a single membrane & contain hydrolytic enzymes in the form of minute crystalline or semi crystalline granules of

How is urea formed in the human body, Q. How is urea formed in the human bo...

Q. How is urea formed in the human body? Urea is a product of the degradation of amino acids, in the process amino acids lose their amine group which is then transformed into

Green glands of crustaceans, Normal 0 false false false ...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Development and differentiation of a flowering plant, Development and Diffe...

Development and Differentiation of a flowering plant The developmental phases of a flowering plant involve seed germination, vegetative growth, flowering, fruiting and senesce

Transcription factors have multiple domains, In most cases, the transcripti...

In most cases, the transcription factors in eukaryotes which bind to promoter   or enhancer sequences   are activator   proteins   which induce   transcription.   That proteins gen

Name some standard activation energy, The standard free energy change and s...

The standard free energy change and standard activation energy for four biochemical reactions are listed in the table below: A few interpretations are given below. Between thes

Detritus food chains, Detritus Food Chains Detritus food chains begin ...

Detritus Food Chains Detritus food chains begin with dead organic matter which is an important source of energy. A large amount of organic matter is contributed by the death o

Report writing, tell me how to write a report in molecular biology?

tell me how to write a report in molecular biology?

PROTOZOA, WHAT IS THE CLASSIFICATION OF PROTOZOA ..

WHAT IS THE CLASSIFICATION OF PROTOZOA ..

What kind of exoskeleton do some molluscs present, Q. What kind of exoskele...

Q. What kind of exoskeleton do some molluscs present? Some molluscs, like gastropods and bivalves secrete an external calcareous carapace (the shell). Calcium carbonate is a fo

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