Why Biodiversity Patterns Matter in Biology
Biodiversity is the variety of life forms that exist on the earth. Several patterns of biodiversity can occur within various species, communities, regions, habitats, biomes, ecosystems and the entire Earth. We can get species-area relationships with the study of biodiversity. Vedantu provides a detailed and easy to grasp explanation, check out its app or download the app.
What is Biodiversity?
Any area or ecosystem rich in Biodiversity ensures a rich gene pool. It is the variety in organisms (plants/animals/microorganisms) that are found at every level of biological organization in the environment. Ecologists have studied and observed a regular pattern in which diversity was distributed over the environment.
Importance of Studying Biodiversity
Biodiversity is an important field of study in Biology. Here is why the study of Biodiversity patterns across different ecosystems and regions is crucial:
It is extremely crucial to have varying life forms in different ecosystems. Rich biodiversity ensures a rich gene pool.
Biodiversity is also important to maintain healthy ecosystems and in turn produce healthy and pure surroundings for us to live in.
With a greater and rich Biodiversity, animals and plants get a variety of food and resources.
Biodiversity thus also contributes to enhancing the economy of a country.
When varying species of animals and plants are studied, they can help in crucial discoveries for the planet earth. Even in the past several important discoveries like vaccinations, antibiotics, medicines, etc were discovered by studying varying life forms on earth.
Studying Biodiversity patterns at different levels helps to keep a check on species that may be on the verge of extinction.
Rich flora and fauna ensure more oxygen in the ecosystem.
It helps in providing clean water and also helps ecosystems to adapt and adjust to natural disasters like forest fires, floods, avalanches, etc.
As can be understood, the richer the Biodiversity, the more important the role it plays for the environment. Thus, the study of Biodiversity can open doors to several important discoveries for our planet. It also helps to be equipped to prevent any further harm to the environment and ensure species can be preserved.
Ecologists observed that species vary at a global level as well as locally; also, species vary over time.
Species Varying Globally - Global pattern of biodiversity has been observed; here, species living in similar habitats are found in different parts of the world are distantly related and act similarly. Examples are Emus that are found in Australia, Rheas found in South America, Ostriches found in Africa, all are flightless birds.
Species Varying Locally - An example is the Galapagos islands that consist of a group of islands that are relatively close to each other but comprise different atmospheres with different climates. So, each island comprises its own species of tortoise and finch that adapt to respective islands.
Species Varying Over Time - An example that we can cite is the modern-day armadillo and the fossil remains of glyptodont that resemble each other.
Latitudinal Gradients Describing Biodiversity Pattern in Species
Latitude: It is a determinant of the angular distance of a place concerning the equator, which ranges from 0° at the Equator to 90° (North or South) at the poles.
Gradient: "direction and rate of fastest increase".
Latitudinal gradients in species diversity explain the diverse existence of species on Earth (Biodiversity) and it varies with change in altitude or latitude. And we can observe an increase in biodiversity when we move from high latitude to low latitude.
We can also say that the diversity of species decreases when we move from the equator towards the poles.
The temperate regions having severe climates will have short growing periods for plants whereas the tropical regions will have a favourable climate for the plants' growth throughout the year. Therefore, rich biodiversity exists in tropical regions because of the favourable environmental conditions that support speciation and enables a larger number of species to grow and flourish.
For example, in tropical rainforests, the vascular species per 0.1 ha sample area or the mean number ranges from 118-236 whereas it is only in the range of 21-28 for the temperate regions.
This type of correlation that exists between diversity and latitude can be observed in a number of taxonomic groups such as butterflies, ants, moths and birds.
Why Latitudinal Biodiversity Gradient Exists?
Tropical latitudes (near the equator) were undisturbed for areas as compared to temperate latitudes (near the poles) i.e. they have a higher collection of species of living organisms whereas the latter is disturbed by glaciers.
Tropical latitudes have a suitable environment for niche and living organisms. In polar or temperate regions, climate changes are unpredictable and the atmosphere is not suitable for living organisms to adapt to the changes. As a result, organisms migrate from those places or die.
Tropical regions organisms will sustain high because of the high availability of more solar energy as compared to the temperate zones.
Species-Areas Relationships
A relationship between species diversity and the area.
Species diversity is the richness of species, i.e. how many different species exist in one area. Also, it describes species evenness, i.e. how evenly the species are distributed in one particular area. Species richness and species evenness constitute species biodiversity. It increases with an increase in explored areas. When species explore other areas than initially found one, they expand their habitat and thus, biodiversity increases. However, other factors govern it such as climatic factors and availability of food to sustain organisms.
Therefore, species diversity will be directly proportional to the explored area. It can be represented in the form of an equation:
logS= log C + Z logA
Where,
S is species richness/evenness.
C is a constant.
Z is the regression coefficient or slope of the curve (can be understood with the help of a graph drawn below).
A is Explored or Particular Area.
Importance of Latitudinal Gradient and Species-Area Relations
Latitudinal gradient and Species area relationships are two integral concepts in the field of Biodiversity. These help us in determining various ecological patterns that exist on earth. One can easily observe through these concepts that species richness increases as one moves from polar regions to tropical climates. As has been mentioned before, determining Biodiversity patterns across the globe is an essential requirement to understand the ecosystems and also take benefit from them. Latitudinal gradient and species-area relationships are two important tools that help in determining such Biodiverosty patterns.
FAQs on Biodiversity Pattern in Species Explained
1. What do we mean by patterns of biodiversity as per the CBSE syllabus for 2025-26?
Patterns of biodiversity refer to the non-random, systematic distribution of species and genetic diversity across different geographical areas on Earth. Instead of being uniform, biodiversity shows clear trends. For instance, the number and types of species change as we move from the equator towards the poles (latitudinal gradient) or from lower to higher altitudes (altitudinal gradient). It also changes with the size of the explored area (species-area relationship). Studying these patterns helps ecologists understand the factors that promote or limit the richness of life in an ecosystem.
2. What are the key patterns that describe the distribution of biodiversity on Earth?
Ecologists have identified two primary patterns that explain the distribution of species diversity, which are fundamental concepts in the NCERT curriculum:
Latitudinal Gradients: This is the most well-documented pattern, showing that species diversity generally decreases as we move away from the equator (0° latitude) towards the poles (90° latitude). The tropical regions near the equator are exceptionally rich in species compared to temperate or polar regions.
Species-Area Relationships: This pattern, proposed by the geographer Alexander von Humboldt, states that, within a region, the number of species found increases with the size of the area explored, but only up to a certain limit. This relationship can be visualised and mathematically described using a species-area curve.
3. How does the species-area relationship explain a pattern in biodiversity?
The species-area relationship explains that larger areas tend to contain a greater number of species. This is because larger areas typically offer a wider range of habitats, more resources, and can support larger population sizes, which reduces the risk of local extinction. This relationship is mathematically expressed by the equation S = CAZ, where 'S' is species richness, 'A' is the area, 'C' is the Y-intercept, and 'Z' is the slope of the line (regression coefficient). On a logarithmic scale, this equation becomes a straight line: log S = log C + Z log A, making it a predictable pattern for ecologists.
4. What is the significance of the slope of regression (Z value) in the species-area relationship?
The slope of the line, or the regression coefficient 'Z', is highly significant as it indicates how rapidly species richness increases with area. For most taxonomic groups and regions, the Z value typically lies in the range of 0.1 to 0.2. However, if the analysis covers very large areas, such as entire continents, the slope becomes much steeper, with Z values ranging from 0.6 to 1.2. A steeper slope means that the number of species increases more rapidly with an increase in area, which is characteristic of continent-wide biodiversity patterns.
5. Why is tropical biodiversity significantly higher than in temperate or polar regions?
There are several hypotheses explaining why the tropics are richer in species:
Greater Solar Energy: Tropical regions receive more direct and intense solar energy, which leads to higher productivity and can support a greater diversity of life.
Stable Climate: Tropical environments are less seasonal and more constant compared to temperate zones. This predictability promotes niche specialisation and the evolution of a greater number of species.
Longer Evolutionary Time: Temperate regions have experienced frequent glaciations in the past, disrupting the evolution and survival of species. The tropics have remained relatively undisturbed for longer periods, allowing more time for speciation (the formation of new species).
6. How is the knowledge of biodiversity patterns applied in real-world conservation?
Understanding biodiversity patterns is crucial for conservation planning. For example, the species-area relationship helps conservation biologists predict the number of species that might go extinct if a habitat is reduced in size due to deforestation or urbanisation. This knowledge is used to design protected areas like national parks and wildlife sanctuaries. By knowing that larger areas can support more species, conservationists can argue for the preservation of large, contiguous tracts of habitat to maximise the protection of biodiversity and minimise extinction rates.
7. Can the patterns of biodiversity, like the latitudinal gradient, have exceptions?
Yes, while the latitudinal gradient is a strong general rule, there are exceptions. Some taxonomic groups show different patterns. For example, while most groups are more diverse in the tropics, certain groups like penguins are concentrated in the Southern Hemisphere, including Antarctica. Similarly, coniferous forests (taiga) in temperate regions have a lower diversity of trees but host a unique community of organisms adapted to that environment. Deep-sea hydrothermal vents are another example of ecosystems with high biodiversity in otherwise low-diversity deep-ocean environments, independent of latitude.
8. How do the biodiversity patterns in India align with global trends?
India's biodiversity patterns align well with global trends while also showcasing unique features. Due to its vast range of climates (from tropical in the south to temperate and alpine in the Himalayas) and diverse landforms, India is a megadiverse country. It demonstrates both latitudinal and altitudinal gradients clearly. For instance, the Western Ghats and the Eastern Himalayas are global biodiversity hotspots, exhibiting immense species richness characteristic of tropical and subtropical regions. The decrease in species diversity as one moves up the Himalayan slopes is a classic example of an altitudinal gradient.
