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

Water reuse and recycling, Water Reuse And Recycling Are Becoming   Much Mo...

Water Reuse And Recycling Are Becoming   Much More Common As Demands For Water Exceed Supply. Unplanned reuse occurs as the result of waste effluents entering receiving waters or g

Enumerate the number of converging developments, Enumerate the Number of co...

Enumerate the Number of converging developments These include: 1) A better definition of the unique developmental concepts that are applicable to infants and young children,

Explain the issues related to food production, Explain the issues related t...

Explain the issues related to food production? Let us now understand some issues related to food production, these are: Factors influencing food production, Analysi

Causes of gerd, In addition, pregnancy or constipation may worsen GERD by i...

In addition, pregnancy or constipation may worsen GERD by increasing intra-abdominal pressure. Secondary causes of GERD include reflux caused by acid hypersecretory states, connec

Explain the menopausal symptoms, Explain the Menopausal symptoms Menopa...

Explain the Menopausal symptoms Menopausal symptoms include: (i) hormone-related gynaecological problems that occur around the menopause, and (ii) post-menopausal uterine

Define briefly about the cereal proteins, Define briefly about the Cereal P...

Define briefly about the Cereal Proteins? Cereal grains, properly ripened and dried for optimum storage stability, have protein content ranging from 6-20%. Proteins are found i

How cells are studied, How cells are studied We learnt about the evolut...

How cells are studied We learnt about the evolution of the cell and a historical account of the growth of cell biology. In this section, you will study about the various tools

Define influence of polyphenols on proteins, Define Influence of Polyphenol...

Define Influence of Polyphenols on Proteins? You know that tannins are considered as anti-nutritional because their presence is usually accompanied by a reduced protein digesti

Genetics, name a disorder of human blood that is caused by mutation

name a disorder of human blood that is caused by mutation

Types of cells in phloem, Types of cells in Phloem The phloem consists...

Types of cells in Phloem The phloem consists of 4 types of cells: i).sieve elements, ii) companion cells, iii) phloem parenchyma and sometimes iv) phloem fibres. The metabolit

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