Natality rate - natality, Biology

Assignment Help:

Natality Rate - Natality

Natality rate or birth rate is determined by dividing the number of individuals born by unit time and is expressed as follows:

Natality rate =  ΔNn / Δt

Δ Nn = production of new individuals in a population

Δ t = unit time

Natality rate can also be determined as the number of new individuals per unit of time per unit of population. This is called specific natality rate and can be expressed as:

Natality rate per unit of population = ΔNn / N Δ t

N may represent the total population or only the reproductive part of the population, i.e. females, for example, in higher organisms natality rate is per female. Natality rate is zero or positive but never negative. The measurement of natality or birth rate is highly dependent on the type of organism being studied. Some species breed once a year, some breed several times a year and others breed continuously. Some produce many seeds or eggs, and others few.

For example, a single oyster can produce 55 to 114 million eggs, whereas birds usually lay between 1 and 20 eggs. Also the specific natality rate differs for individuals of different age groups in the population. For example in a rabbit population for 1 to 2 year old females the specific natality rate is average 4 young ones per year per female, while for females of less than 1 year the rate is 1.5 on an average. Since natality is the concept referring to the population and not to the isolated individuals, the average reproductive capacity should be taken as the measure of natality, and not the capacity of the most productive or least productive individuals.

 


Related Discussions:- Natality rate - natality

Rules of nomenclature classification, Q. Rules of Nomenclature classificati...

Q. Rules of Nomenclature classification? The Rules of Nomenclature prescribed the categories into which plants should be classified. These categories constitute the units of cl

How mathematics and statistics related to biology, How mathematics and stat...

How mathematics and statistics related to Biology? This report emphasizes the benefits that the fields of mathematics and statistics can bring to biology, but there are recipro

Which are the plant tissues that cover the stem and leaves, Which are the p...

Which are the plant tissues that cover the stem and the leaves? The stem may be enclosed by epidermis (having stomata, cuticle and photosynthetic cells) as in monocots or, alte

Define regulation of water balance, Define Regulation of Water Balance? ...

Define Regulation of Water Balance? The input of water, as well as, its loss can be highly variable due to individual habits and environmental factors; in spite of this, the to

Medical management of chronic renal failure, Medical Management   In ch...

Medical Management   In chronic  renal failure  there  is irreversible renal failure. The goals of medical management are:   To promote maximal  renal  function  To ma

Symptoms of constipation, Q. show the Symptoms of constipation? Have yo...

Q. show the Symptoms of constipation? Have you ever suffered from constipation? Do you recall the symptoms associated with the problem? Yes, the symptoms were specific to havin

What are flavanols, What are Flavanols? Examples are catechin and epica...

What are Flavanols? Examples are catechin and epicatechin. You may have heard of the benefits of tea. Some of them are due to gallic acid, which is combined with epicatechin. F

Explain human cells that produce proteins for exportation, What are some ex...

What are some examples of human cells that produce proteins for exportation? Which cytoplasmic organelle is expected to be well-developed and abundant in those cells? Specializ

Cerebellum, why cerebellum more developed in mammals that jump or fly?

why cerebellum more developed in mammals that jump or fly?

How do you define normal pulmonary vasculature, Q. How do you define Normal...

Q. How do you define Normal Pulmonary Vasculature? Pulmonary vessels are seen in the medial 2/3 of the lung. Vessels are generally not identified in the lateral third. The rad

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