Biodiversity Patterns in Species and Their Distribution

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.