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

Describe population and the frequency of the melanics, In one study of a he...

In one study of a heavily polluted area near Birmingham, England, a researcher observed a frequency of 87% melanic Biston betlularia. Calculate the frequency of the dominant allele

Zone of polarizing activity (zpa), Zone of Polarizing Activity (ZPA) T...

Zone of Polarizing Activity (ZPA) The A-P axis is the 1 st axis to be fixed in the presumptive limb mesoderm at a very early stage. On the basis of results of a series of cur

Describe retroviruses and how do they reproduce, Q What are the retroviruse...

Q What are the retroviruses? How do they reproduce and what is the role of the enzyme reverse transcriptase? Retroviruses are viruses whose genetic material is RNA, HIV and the

01.03 new technology, What is the best microscope to get a detailed view of...

What is the best microscope to get a detailed view of the parts inside of a preserved plant cell?

Explain adverse effects of efavirenz, Adverse effects of Efavirenz The ...

Adverse effects of Efavirenz The most common adverse effects have been rash, dizziness, headache, insomnia and inability to concentrate. Vivid dreams, nightmares and hallucinat

Rapport - building, Rapport-Building Here the Counsellor tries to esta...

Rapport-Building Here the Counsellor tries to establish a rapport and gain the client's trust. Let us see how we make friend? When we meet someone we take time to react, we ob

Determine the evaluation of the bone, Evaluation of the bone Evaluation...

Evaluation of the bone Evaluation of the bone -implant interface needs to be done by the following: Failures in Implant Dentistry 1) Implant mobility and discomfort 2)

Digestive system, which enzymes are required for digestion in cockroach?

which enzymes are required for digestion in cockroach?

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