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Biodiversity

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What is Biodiversity?

MVSAT 2024



Biological diversity or Biodiversity is the differences and variety between the living organisms of all sources. It includes all terrestrial (land-dwelling), marine (aquatic) and other different ecosystems and ecological complexes.


Biodiversity Definition

Biological diversity largely describes the change of life from genes to ecosystems, comprising their existences, genetic variations, their environment, populations and the ecosystem in which they are existing and other evolutionary developments that keep the system functioning, changing and adapting.

 

Biodiversity is distributed into different components based on the level of differences.

 

Types of Biodiversity

Genetic Diversity – It is the diversity expressed at the genetic level by every single person in a species. No two individuals of the same species are accurately similar. For instance, humans show a lot of biodiversity between themselves. People living in different areas show a great level of differences.

 

Species Diversity – It is the biodiversity seen within a community. It signifies the number and distribution of species. The number of species in an area varies broadly according to the environmental surroundings. For instance, it is usually observed that a human society living nearby the water bodies display more species than the one compared to the areas far from water bodies.

 

Ecological Diversity – It is the diversity seen between the ecosystems in a region. Several ecosystems like rainforests, deserts, mangroves, etc., show a vast diversity of life forms living in them.

 

Genetic Diversity: It is the diversity expressed at the genetic level by every single person in a species. It is distinguished from genetic inconsistency, which describes the tendency of genetic features to differ.

 

Genetic diversity works as a way for populations to adjust to changing environments. With more differences, it is more likely that certain individuals in a population will have variations of alleles that are right for the environment. Those individuals are more expected to survive to yield offspring bearing that allele. The population will continue for extra generations because of the success of these individuals.

 

The abstract field of population genetics contains some hypotheses and theories about genetic diversity. The neutral theory of evolution suggests that diversity is the outcome of the accumulation of neutral replacements. Varying selection is the hypothesis that two subpopulations of a species exist in different surroundings that select for different alleles at an exact locus. This might occur, for example, if a species has a wide range relative to the flexibility of individuals within it. Frequency-dependent selection is the hypothesis that as alleles become extra common, they become extra vulnerable. This occurs in interactions between host and pathogen, in that a high rate of a defensive allele between the hosts means that it is more likely that a pathogen will spread if it is capable of overcoming that allele.

 

Adaptation

The difference in the populations’ gene pool permits natural selection to act upon characters that allow the population to adjust to changing environments. Selection for or against a characteristic can happen with changing the environment – resulting in a rise in genetic diversity (if a new mutation is selected for and preserved) or a drop in genetic diversity (if a disadvantageous allele is selected against). Therefore, genetic diversity plays a vital role in the survival and adaptability of a species. The ability of the population to adjust to the changing environment will rest on the presence of essential genetic diversity. The more genetic variety a population has the more possibility or the chance of the population will be able to adapt and survive. Equally, the vulnerability of a population to changes, like novel diseases or climate change will increase with a fall in genetic diversity. For instance, the inability of koalas to adjust to fighting the koala retrovirus (KoRV) and Chlamydia has been connected to the koala’s low genetic diversity. This low genetic diversity also has geneticists worried about the koala's ability to adjust to climate change and human-induced environmental variations in the future.

 

Species Diversity 

It is the biodiversity seen within a community. It signifies the number and distribution of species. The effective number of species refers to the number of similar copious species needed to obtain the same mean proportional species abundance as that is seen in the dataset of interest. Species diversity contains three components: species taxonomic, richness or phylogenetic variety and species consistency. Species richness is a common count of species, taxonomic or phylogenetic diversity is the genetic relationship among different groups of species, whereas species consistency quantifies how equal the abundances of the species are.

 

Calculation of Diversity

The species diversity can be measured by first taking the weighted mean of species proportional plenty in the dataset, and then taking the opposite of this. The equation is:

 

\[ ^qD = \frac{1}{\sqrt[q-1]{\sum_{i=1}^{S} p_{i}p_{i}^{q-1}}} \]

 

The denominator equals average proportional species abundance in the dataset as measured with the weighted generalized mean with exponent q - 1. In the equation, S represents the total number of species (which is species richness) in the dataset, and the proportional abundance of the species is {\displaystyle p_{i}}pi. The proportional abundances themselves are considered as weights. The equation is often expressed in the equivalent form:

 

\[ ^qD = (\sum_{i}^{S}p_{i}^{q}) ^\frac{1}{(1-q)}\]

 

The value of q describes which kind of mean is used. q = 0 resembles the weighted harmonic mean, which is 1/S since the {\displaystyle p_{i}}Pivalues cancel out. q = 1 is undefined; excluding that the limit as x approaches 1 is well defined:

 

\[\lim_{{q }\rightarrow {1}}\] \[^{q}D = exp( - \sum_{i=1}^{S} p_{i }lnp_{i})\]

 

q=2 corresponds to the mathematics mean. As q reaches infinity, the generalized mean reaches the maximum Pi value. In practice, q modifies species weighting, such that increasing q raises the weight given to the most copious species, and less equally abundant species are therefore required to reach mean proportional abundance. As a result, large values of q will lead to minor species diversity than small values of q for a similar dataset. If all species are in the same way abundant in the dataset, altering the value of q has no effect, but species variety at any value of q is equal to species richness.

 

A similar equation can be used to measure the diversity with any taxonomy, not only species. If the persons are classified into functional types or general types, Pi is the proportional abundance of the genus or functional type, and qD is equal to genus variety or functional type variety, respectively.

 

Ecological Diversity

It is the diversity seen between the ecosystems in a region. Keeping both kinds of diversity is fundamental to the working of ecosystems and therefore to human welfare. India is one of the 12 centres of diversity and origin of numerous cultivated plants in the world. It is expected that 15,000 species of plants arise in India. The flowering plants contain 15,000 species of which some hundred (5000-7500) species are common to India. The region is also rich in fauna, holding about 65,000 species of animals.

 

Among them, more than 4,000 molluscs, 50,000 species of insects. 2,000 fish, 140 amphibians, 420 reptiles, 6,500 other invertebrates, 1,200 birds and 340 mammals are documented from India. This abundance in biological diversity is due to a huge variety of climatic and altitudinal conditions combined with diverse ecological habitats.

 

These differ from the cold desert of Ladakh and the icy mountains of the Himalayas to the warm coasts of peninsular India including the coastal region of Orissa, from the damp tropical Western Ghats to the hot desert of Rajasthan. Gandhamardan Hills of Sambalpur is rich in biodiversity. The Indian tradition teaches us that all types of life, human, animal, and plant are so closely related that disturbance in one gives rise to the imbalance to the other.

 

Importance of Biodiversity

All these diversities help in keeping the balance in nature. But, slowly there has been the loss of biodiversity. The loss of biodiversity can badly affect our environment as the balance is lost and the natural food chain is disturbed. So, as we realize its significance in our existence, biodiversity conservation has now become a matter of high significance.

 

We still have not branded all the species living on the earth but of all the ones known till now, several have now been marked as extinct. Recently, the rate of extinction has gone much higher and this is causing direct influence on our earth like overuse of resources at some portions, the overpopulation of some species, etc. This has produced a huge imbalance in nature. Thus, the importance of biodiversity has to be understood and steps have to be taken to preserve all three diversities.

 

Healthy Biodiversity delivers Many Natural Services for Everyone:

  • Ecosystem services, like

  • Soils formation and protection

  • Nutrient storage and recycling

  • Pollution breakdown and absorption

  • Protection of water resources

  • Contribution to climate stability

  • Maintenance of ecosystems

  • Recovery from unpredictable events

  • Biological resources

  • Food

  • Future resources

  • Medicinal resources and pharmaceutical drugs

  • Ornamental plants

  • Wood products

  • Diversity in genes, species, and ecosystems

  • Breeding stocks, population reservoirs

  • Social benefits,

  • Research, education, and monitoring

  • Recreation and tourism

  • Cultural values

 

That is pretty a lot of services we get for free!

 

The cost of replacing these (if possible) would be enormously expensive. It hence makes economic and development sense to move towards sustainability.

 

More about Biodiversity 

The term “biodiversity” usually refers to the broadest definition of the diverse array of living organisms found in an ecosystem. However, with many species becoming extinct, it is becoming increasingly important to consider the diversity of the world in ways other than just genetic diversity.

 

In the biological diversity, you'll find a rich array of living organisms from microscopic microorganisms and fungi to large animals and plants. Your biodiversity is a wonderful asset, for it provides you with several important benefits. By learning more about biodiversity and conserving it, you can improve your overall health and well-being.

 

Biodiversity is very important for you to be able to develop. It is important to remember that in nature there is always a balance between the food supply and the demand for it.

 

The food supply is what is called your food chain. When the food supply is greater than your demand, then there is plenty of food for the animals in the food chain. When the food supply is less than your demand, then the demand goes hungry. It is in your best interest to maintain a healthy and balanced food supply and demand.

 

Your food chain consists of plants, animals and soil. You should care for the soil because it is the base of the food chain. If there is a lack of a proper food chain it is very important to provide additional food in the form of plants.

 

The food supply of plants is very important and it is the base for all life. One of the major problems with biodiversity is that human beings are destroying it by its very presence.

 

It is important to remember that plants depend on the soil for their growth, not on the sun. Your soil is your biggest customer and it is what you must supply.

 

You cannot live without plants. There are so many that we never even notice them. Yet, they are an important part of your daily diet and of the environment that you live in. Plants convert your sunlight to energy for you. They absorb your toxins and give you the oxygen you breathe.

 

The soil is the only place where life begins. The soil also provides a living space for many animals to live on land. Without plants, we would not be able to grow any food. Many of our food items, even meat, come from plants.

 

Soil is the primary living component of your food chain. If you neglect the soil you will not have a healthy food chain. We live in an age where some people think of soil as something to move to get away from people. I believe that soil should be the first thing you protect. It is your first contact with nature. It is the only way to get a quality of life.

 

Some people are so removed from the soil that they never even notice it. It is a part of their existence and yet they have no idea of how important it is. The first place to start protecting your soil is to grow plants and to maintain the soil where you live.

 

The more organic matter you have in the soil, the more oxygen will be available for the microorganisms that live there. If you want to protect your soil you must have healthy soil. As you begin to understand the importance of soil you will have many health benefits. Let’s start with your lungs.

 

Plants and soil help to oxygenate our blood and as a result, they help to protect our lungs from the unhealthy air we breathe all the time. There are so many diseases associated with air pollution.

 

Your stomach will benefit from eating the soil you live in. The healthy microbes that live in the soil will help to create the microorganisms that protect your stomach lining and help to create an acidic balance in the stomach.

 

Plants absorb nutrients from the soil that help to feed them and in turn, the plants feed us. The plants do more for us than just keep us alive. They also have healing qualities as well.

 

Foods that contain plants help you to maintain a healthy digestive tract. Plants need light to live and the soil where you live protects you from the sunlight. Protecting the soil will help you to have a healthy immune system.

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FAQs on Biodiversity

1. What is the definition of biodiversity?

Biological diversity largely describes the change of life from genes to ecosystems, comprising their existences, genetic variations, their environment, populations and the ecosystem in which they are existing and other evolutionary developments that keep the system functioning, changing and adapting. Biodiversity is distributed into different components based on the level of differences.  Biodiversity – the entire collection of life forms on a particular planet – is a key component of a healthy environment. It is defined as the number and variety of species of all organisms, either living or once-living, present in a given area. It is also often referred to as biological diversity.


It is important to note that different forms of biodiversity, such as the genetic diversity of species or species diversity within an area, may or may not have the same biological significance. However, the scientific community is now generally agreed that measures of species diversity should be considered when assessing biodiversity.


The main sources of biodiversity are plants, animals and their offspring, which are in turn the sources of ecosystem goods and services, such as food production. So the value of these services is affected by the number and distribution of species. Although the diversity of a particular area may vary, overall diversity is thought to be fairly stable within a country but can be quite variable across continents.


Biodiversity is important for humans. While many studies have identified the benefits of biodiversity, there is no clear evidence that these benefits necessarily increase with the extent of biodiversity. We don’t know exactly why biodiversity is important, but it is almost certainly because of the way that biodiversity affects how life functions.

2. What is the formula for calculating the diversity?

The species diversity can be measured by first taking the weighted mean of species proportional plenty in the dataset, and then taking the opposite of this. The equation is


\[D = 1 - \frac{\sum n (n-1)}{N (N-1)}\]

Where : 

n = number of individuals of each species 

N = total number of individuals of all species

3. Where can I find the notes on Biodiversity - Definition, Types of Biodiversity and Its Importance?

Biodiversity is the variety and abundance of life, from the genetic level of a single cell to a whole ecosystem. Biodiversity includes many levels of biodiversity, including species, genetic diversity, genetic differences, gene pools, gene clusters, ecosystems, and communities. We are at a critical transition point in human history - one in which we face the greatest challenge in human history - the survival of the human species on this planet. Biodiversity is an invaluable element of our environment and an important element of our well-being. It is a key component of our sustainable future. Biodiversity provides the raw material for the natural selection process, the evolution of higher life forms, and the creation of new genes. Biodiversity provides a source of genetic resources, which is a key component of our future.


Biological diversity or Biodiversity is the differences and variety between the living organisms of all sources. It includes all terrestrial (land-dwelling), marine (aquatic) and other different ecosystems and ecological complexes. Vedantu is a platform that aims at making students well prepared for the final exams and therefore it provides answers to all the questions of previous year question papers obtained from expert teachers in the subject which can be downloaded either through the app or website.

4. What is the role of human beings in the Biodiversity conservation crisis? Explain with an example.

Around 1400 animal species and 15000 plant varieties have Borneo, an iconic southeast Asian island, as their only home. Wildlife varieties of rare breeds such as clouded leopard, rhinos, pygmy are found in abundance. It also houses some of the tallest southeast Asian tropical trees. Colour-changing frogs, a wide variety of slugs, orchids of rarest species are all present here. The island provides a wide treasure of hardwood trees, gold, rubber, coal, minerals, diamonds, which is continuously being exploited by us humans. Indirectly we humans are turning out to be the biggest threats to biodiversity. 


Several forests have been wiped out just to make palm oil plantations extract oil. Many animals are sold in the Black Market for a high rate, both alive and in parts. The largest known carnivore is on the verge of extinction, more than one-fourth of the forests are cleared, and almost 50% of Borneo orangutans are endangered. If we continue to pluck threads from the original web, the biodiversity chain is bound to collapse. 

5. What are Biodiversity and conservation?

Especially after answering questions like why is biodiversity important, or what is biodiversity and many more, we know clearly that all the different types of lives found in a particular area is the original definition of biodiversity. These lives consist of everything that is a part of nature, like even the bacteria and viruses you see around, fungi, plants, animals, various forms of creatures, and more. All these organisms work together as one to form an intricate web and support the basic essence of life or the ecosystem to maintain the balance of life. Biodiversity is something, which consists of everything that we need for survival, such as food, shelter, security, clothes and more. 


The main threats to biodiversity are due to climatic changes and extreme exploitation of the earth's natural resources. We have already initiated an initial loss of our ecosystem and biodiversity by clearing out forests and polluting natural resources like water, air, soil, and more. The houses in the urban area are not the main victims of such changes, but the remote areas are being affected. Hence, the study of different types of biodiversity conservation becomes extremely important. 


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