Imagine making a list of all of the species you have ever heard of; it would be an enormous list! There are many different species on this planet. This lesson will explore the diversity of species, as well as the different types of diversity and how diversity of life is essential for maintaining healthy ecosystems.
What Is Biodiversity?
Did you know there are more than 10,000 species of birds, 200,000 species of flowering plants and almost one million species of insects in the world? The number of species identified has increased substantially in recent years, and there are over 1.
5 million species currently known. Although this number might seem large, it is thought that this number is actually only a fraction of the number of species that exist today. New species are being identified every day, and it is estimated that there are anywhere between three and fifty million different species living on Earth.When discussing the number of species on earth, the term biodiversity is often mentioned. Biodiversity, also known as biological diversity, is the variety of life on Earth across all of the different levels of biological organization. On a smaller scale, biodiversity can be used to describe the variety in the genetic makeup of a species, and on a larger scale, it can be used to describe the variety of ecosystem types.
Types of Biodiversity
Biodiversity is a very broad term and is often divided into three types.
The first type of biodiversity is species diversity, and this is the type of biodiversity most people are familiar with. Species diversity is defined as the number and abundance of different species that occupy a location. To accurately determine species diversity, both the species richness, which is the number of different species, and the relative abundance, which is the number of individuals within each species, must be considered. An example of species diversity would be the number and abundance of different types of mammals in a forest.
The second type of biodiversity is genetic diversity. Genetic diversity is the amount of variation in genetic material within a species or within a population. There is a high level of diversity among species, but there is an even higher level of diversity among the genetic material of the individuals of a specific species. An example of genetic diversity is the variation in the genes that encode for hair color in humans.The third type of biodiversity is ecological diversity, and this is the variation in the ecosystems found in a region or the variation in ecosystems over the whole planet.
Ecological diversity includes the variation in both terrestrial and aquatic ecosystems. Ecological diversity can also take into account the variation in the complexity of a biological community, including the number of different niches, the number of trophic levels and other ecological processes. An example of ecological diversity on a global scale would be the variation in ecosystems, such as deserts, forests, grasslands, wetlands and oceans. Ecological diversity is the largest scale of biodiversity, and within each ecosystem, there is a great deal of both species and genetic diversity.
Biodiversity and Ecosystem Stability
Now that you know what biodiversity is, why do you think it might be important? Biodiversity is important not only for the variety of beautiful and interesting species it offers us, but it is also very important (and vital) to the stability of an ecosystem and our entire planet. Ecosystem stability is the ability of an ecosystem to maintain a steady state, even after a stress or disturbance has occurred. In order for an ecosystem to be considered stable, it needs to have mechanisms in place that help it return to its original state after a disturbance occurs.It has been shown that biodiversity of an area has a large impact on the ecosystem stability of that area. Areas with high levels of species and genetic diversity are likely to have a more complex ecosystem, with a variety of food webs and biotic interactions. This increase in complexity makes it more likely that the ecosystem will return to a stable state after a disturbance, because the ecosystem has more ways to respond to a disturbance and fix problems.For example, let’s examine how two imaginary ecosystems with variations in biodiversity might respond to the same disturbance.
The first ecosystem has only three species of trees, and the second ecosystem has over 30 species of trees. Now imagine both of these ecosystems are in a region that has just experienced a large fire. In the ecosystem with the higher level of species diversity, you would expect that the ecosystem would recover more quickly after the fire. This is because the larger amount of diversity makes it more likely that some of the species are better adapted for fires and can recover more quickly.In the ecosystem with the lower species diversity, you are relying on only three different species to repopulate the area. If any of these species are not adapted to recover from fire, the ecosystem will have a harder time returning to a steady state after the disturbance, due to the lack of diversity.
With over 1.
5 million species already identified and potentially millions more awaiting discovery, our planet is a very diverse and mysterious place. Due to the large number of species found on earth, there is a great deal of diversity. Biodiversity is the term used to describe the variety of life on earth across all of the different levels of biological organization. Biodiversity is often divided into three types, including species diversity, genetic diversity and ecological diversity.Species diversity is the number and abundance of species that occupy a location. Genetic diversity is the amount of variation in genetic material within a species or within a population. The third type of biodiversity is ecological diversity, and that is the variation in the ecosystems found in a region or the variation in ecosystems over the whole planet.
Overall, biodiversity is very important, because it helps maintain ecosystem stability, which is the ability of an ecosystem to maintain a steady state, even after a stress or disturbance has occurred. With higher levels of biodiversity, ecosystems are more likely to recover after a disturbance, because their increased complexity gives them more opportunities and methods for recovering. Our planet is always changing, and it is important to maintain a high level of biodiversity throughout the whole planet, because it will make it more possible for species and ecosystems to adapt to, and survive, dramatic environmental changes of the future.
After this lesson, students should be able to:
- Define biodiversity
- Describe species, genetic and ecological diversity, and give examples of each
- Define species richness and relative abundance, and understand their importance in determining species diversity
- Explain the importance of biodiversity in maintaining ecosystem stability