Biodiversity Pattern Species: Definition, Types, Patterns, Relationship, examples

What are Biodiversity Patterns?

Biodiversity refers to the sum total of all living organisms present on the Earth. Patterns of biodiversity refers to non-uniform distribution of life on Earth There are two main trends observed called Latitudinal Gradient and Species-Area Relationship. In latitude gradient the diversity decreases from the equator to the poles while in the Species-Area Relationship shows more species in larger areas

Global and Local Biodiversity Variation

Global Variation

Since they share many traits, creatures from different parts of the world may be distantly related according to one biodiversity pattern. In terms of appearance and behaviour, emus, rheas, and ostriches are all comparable. They are all unable to fly.

Local Variation

A range of habitats for different species within a constrained area defines this biodiversity pattern. The temperatures of the Galapagos Islands are incredibly diverse despite their proximity. The biological conditions and tortoise shells on the various islands vary. The high peaks of Isabela Island receive more rainfall than the rest of the island and are covered in luxuriant vegetation. A short neck and a canopy shell characterise the tortoise on this island. Hood Island has a drier climate, lower elevations, and fewer trees and bushes. This tortoise can be distinguished from other species by its thick neck and saddle-backed shell. Researchers have also noted that the mockingbird species found on various islands are distinct.

Types of Biodiversity Patterns

The ecosystems contain diversity in the living organism. The evolution of biodiversity is influenced by both the passage of time and variations in distance from the equator. It is unquestionably the most precisely defined pattern in all of nature.Diversity develops in accordance with two distinct patterns, each of which has its unique way:

Latitudinal gradients

The variety of species increases as we move closer to the equator and decreases as we move closer to the pole. The equator contains more biodiversity than the poles. A few species represent an exception to this rule. India is home to a diverse range of animals due to its position in a tropical area.

The Amazon jungles are the most biologically diverse in the world regarding the number of species. The climate in the Tropics (latitudinal range of 23.50 N to 23.50 S) is steady in contrast to temperate regions. In this area, species don't have to adapt to the changing seasons sparingly. Therefore, we might see a broader range of species.

Tropical latitudes have stayed mostly unmodified for millions of years, giving enough chance for biological diversity, in contrast to temperate regions that have periodically endured glacial.

Species-Area Relationships

There is a correlation between species richness and region size. Alexander von Humboldt made this discovery. If the area increases, the number of species also increases, but not proportionally, it rises at a slower rate. The connection is shown as a straight line on a logarithmic scale.

log S = log C + Z log A

where,

S = richness of species

C = Y-intercept

Z = regression coefficient

A = Area

Biodiversity Pattern Over Time

Evolutionary Pattern: As a result of animal evolution, biodiversity has risen over the past 600 million years in every regime and epoch. While other species are extinct but may still be found as living fossils, others are depicted as missing or extant connections on the evolutionary timeline.

Successional Pattern: Following a disturbance, plants and animals start to retake the region in a successional pattern. When another species replaces them, they go extinct. Success describes this pattern of changing species composition over time.

Seasonal Pattern: Species diversity changes as the seasons' change. The number of bug species fluctuates over the wet season. The number of birds in the area is influenced by the migratory and breeding seasons.

Importance of Studying Biodiversity Pattern

Studying biodiversity patterns is important because it helps us understand how life is distributed on Earth and why some regions are richer in species than others. This knowledge is crucial for conservation, sustainable use of resources, and predicting the impact of climate change.

Conservation Planning: It helps to identify biodiversity “hotspots” like the Himalayas and Indo-Burma region where urgent protection is needed.

Sustainable Use of Resources: It guides humans in using biodiversity without exhausting it.

Understanding Ecosystem Services: It shows how species contribute to food, oxygen production, pollination, and nutrient cycling.

Predicting Impacts of Climate Change: The patterns help scientists forecast how global warming may shift species distributions.

Biodiversity Pattern NEET MCQs

Q1. Select the incorrect statement

1. Tropical areas have more species as compared to polar or temperate areas.

2. Diversity increases as we move away from the equator.

3. Columbia, located near the equator, has 1400 species of birds.

4. None of these are incorrect.

Correct answer: 2) Diversity increases as we move away from the equator.

Explanation:

The diversity is not uniform, rather it is present in the form of uneven distribution. For the majority of groups and animals, a latitudinal gradient pattern can be observed. Usually, the diversity of species decreases as we move away from the equator, toward the poles. Therefore, the tropics harbor has more species as compared to polar or temperate areas.

Colombia, located near the equator, has around 1400 species, while New York at 41 degrees north has 105 species, and Greenland, at 71 degrees north has 56 species.

Hence, the correct answer is option 2) Diversity increases as we move away from the equator.

Q2. Which of the following regions of the globe exhibits the highest species diversity?

1. Western Ghats of India

2. Madagascar

3. Himalayas

4. Amazon Forests

Correct answer: 4) Amazon Forests

Explanation:

Amazon forests have the highest diversity of plants and animals on the earth. The Amazon rainforest is the most biodiverse ecosystem on Earth, hosting millions of plant, animal, and microbial species. Its warm, humid climate and vast expanse provide ideal conditions for a wide range of flora and fauna to thrive. The dense forest canopy supports numerous unique species, including jaguars, macaws, and anacondas, many of which are found nowhere else. This rich biodiversity plays a crucial role in maintaining global ecological balance and climate regulation.

Hence, the correct answer is option 4) Amazon Forests

Q3. The relationship between species richness and area is a straight line as per the equation. However, on the logarithmic scale it can be defined as

1. logS = logC + logZ

2. logS = logZ + logA

3. logS = logC + ZlogA

4. logS = logA + ClogA

Correct answer: 3) logS = logC + ZlogA

Explanation:

As learned in Patterns of Biodiversity - Species-Area relationships -

The species-area relationship (SAR) is expressed as log⁡S=log⁡C+Zlog⁡A\log S = \log C + Z \log A, where S is species richness, A is area, Z is the slope (indicating how richness changes with area), and CC is the y-intercept (richness at a unit area). This equation, derived from S=C⋅AZS = C \cdot A^Z, linearizes the relationship on a logarithmic scale, showing that species richness increases predictably with area. It’s a key ecological concept, with Z typically ranging between 0.2 and 0.4, reflecting greater habitat diversity and reduced extinction risk in larger areas.

Hence, the correct answer is option 3) logS = logC + ZlogA.

Also Read:

• MCQs on Patterns of Biodiversity

• Biodiversity Loss and Causes

• Ecosystem Services

FAQs on Biodiversity Pattern

What are biodiversity patterns?

Biodiversity patterns describe how species are distributed across the Earth. These patterns include differences in the number of species across latitudes, regions, and habitats. The two most studied patterns are the latitudinal gradient and the species–area relationship.

What is the latitudinal gradient of biodiversity?

The diversity of plants and animals is not uniform throughout the world but shows a rather uneven distribution. Generally, biodiversity increases from the poles to the equator. This pattern is known as the latitudinal gradient. It is due to factors like higher energy input, more stable climate, and longer evolutionary time in tropical regions compared to temperate and polar areas..

What is the species–area relationship?

German naturalist and geographer Alexander von Humboldt observed that within a region, species richness increased with increasing explored area, but only up to a limit. It follows a predictable pattern. If the area increases, the number of species also increases, but not proportionally, it rises at a slower rate. The relationship is described by the equation:

log S = log C + Z log A

where,

S= Species richness A= Area

Z = slope of the line (regression coefficient)

C = Y-intercept (unit of measurement of area)

Why are the tropics rich in biodiversity?

Tropical environments, unlike temperate ones, are less seasonal, relatively more constant and predictable. Such constant environments promote niche specialization and lead to greater species diversity. There is more solar energy available in the tropics, which contributes to higher productivity. This in turn might contribute indirectly to greater diversity. Long evolutionary history without drastic climatic changes allowed species to diversify.