Population regulation, Biology

Assignment Help:

Population Regulation

The number of individuals in a natural population varies with time. If the size of a population declines too drastically due to some reason, it may become extinct, but may later be re-established by immigration from other populations. On the other hand, increase in size of a population is not infinite since the carrying capacity of the environment always imposes a restriction upon it. In spite of such fluctuations, however, an outstanding feature of most large populations is that their average size changes relatively little over the years and certainly less than is expected from their biotic potentials. This indicates that population sizes are regulated in such a way that small population grow fast, larger populations grow more slowly and still larger populations decline.

Let us see what brings about such ecological homeostasis. In low-diversity, physically stressed ecosystems or in those subjected to irregular or unpredictable external perturbations, populations tend to be regulated by physical components such as weather, water, chemical limiting factors, pollution etc. In high diversity ecosystems, or in those which are not physically stressed, populations tend to be biologically controlled. In all ecosystems there is a strong tendency for all populations to evolve through natural selection towards self-regulation such as failure of reproduction and self-inflicted mortality. Even though this is difficult to achieve under external stress. It is because over-population is not in best interests of any population. Thus it can be said that limitation of number in any population is brought about by the action and interaction of two basic regulatory processes namely density dependent and density independent factors. We will discuss these processes in the following subsections.


Related Discussions:- Population regulation

Will any cell verify the cell theory, Of the cell types observed (Parameci...

Of the cell types observed (Paramecium, Euglena, Yeast, Elodea, cheek cells), would any cell "verify" the cell theory? Explain your answer.

Pathogenesis of viruses, Pathogenesis of Viruses Viral diseases An...

Pathogenesis of Viruses Viral diseases An indicated before, viruses cause a number of infectious human diseases from minor ailments like common cold, to fatal disease, lik

Explain about the methods of food processing, Explain about the Methods of ...

Explain about the Methods of Food Processing? In the earlier unit we learnt about the principles and traditional methods of food processing. Now in the next two units we will f

What are the main types of waste, Q. What are the main types of waste? ...

Q. What are the main types of waste? The waste can be classified into many kinds, each of them carrying its own different environmental problem: recyclable waste, organic waste

Explain the canal obstruction - endodontic retreatment, Explain the Canal O...

Explain the Canal Obstruction File work shorter than the normal apical and feel a great resistance to reach true length. a. A retained instrument o Canal calcification b.

What is the importance of the glucose blood level, What is the importance o...

What is the importance of the glucose blood level for human health? The glucose blood level (glycemia) must be kept normal. If it is abnormally low there is not enough glucose

Predation, Think back to the patterns of predator-prey cycling from Section...

Think back to the patterns of predator-prey cycling from Sections 2 and 3. Which of the three predator functional responses would you expect to be most likely to give stable popula

What are the processes that autotrophic beings, What are the processes that...

What are the processes that autotrophic beings use to produce organic material from inorganic substances? The Autotrophic beings make organic material by photosynthesis or by c

Purchasing of service, Normal 0 false false false EN-IN...

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

What is mass transportation across the cell membrane, Mass transportation i...

Mass transportation is the access or the exiting of substances in or from the cell engulfed by portions of membrane. The fusion of internal substance-having membranous vesicles wit

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