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

What would be the flow rate, The physician orders 2 liters of lactated ring...

The physician orders 2 liters of lactated ringers over 16 hours. The drip factor of the tubing is 20 gtt/cc. What will be the flow rate? a. 33.33 or 34 gtt/min b. 41.66 or 42

Describe about aorto pulmonary window, Describe about Aorto Pulmonary Windo...

Describe about Aorto Pulmonary Window ? This uncommon malformation consists of communication usually non-restrictive between the adjacent walls of the ascending aorta and pulmo

What is wall resistance of plant cells, Q. What is wall resistance of plant...

Q. What is wall resistance of plant cells? Does this resistance make difficult the entrance of water into the cell or facilitate? Turgor Pressure TP, or Wall resistance, is the

Measurement of species diversity, The measurement of species diversity prov...

The measurement of species diversity provides an important preliminary assessment of overall biodiversity. There are many ways by which species diversity is measured i.e. species r

Locomotion in arthropoda, Locomotion in Arthropoda The Arthropods are...

Locomotion in Arthropoda The Arthropods are characterized by the existence of some special features which can be considered key to their success. These involve a rigid exoske

#title.zoology., #question.why obelia is considered of special interest in ...

#question.why obelia is considered of special interest in zoology.

What is the significance of axial skeleton, What is the significance of Axi...

What is the significance of Axial skeleton? The bones which make up skeleton of the main body axis of vertebrates. It comprise the cranium, vertebral column, and rib cages, How

What is flap tearing, What is Flap tearing Poor preoperative surgical p...

What is Flap tearing Poor preoperative surgical planning can result in flap of small size with inadequate exposure of the underlying bone. In an effort to increase the visibili

Skeleton, what are the biological significance of the skeleton?

what are the biological significance of the skeleton?

Test for starch, have any picture this expiriment at record?

have any picture this expiriment at record?

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