Ecology And Environment

The task is to match the extinct animals listed in List-I with their corresponding places in List-II. We start by identifying each animal and the region it is known from:

1. Dodo - The Dodo was a flightless bird that lived on the island of Mauritius. Hence, (A) matches with (III).

2. Quagga - The Quagga was a subspecies of the plains zebra, found in South Africa. Therefore, (B) matches with (I).

3. Thylacine - Also known as the Tasmanian Tiger, it was native to Tasmania, Australia. Hence, (C) corresponds with (IV).

4. Steller’s Sea Cow - This marine mammal was found in the waters around the Commander Islands in the Bering Sea, near Russia, giving (D) a match with (II).

From this, the correct mapping is (A) - (III), (B) - (I), (C) - (IV), (D) - (II).

The Verhulst-Pearl Logistic Growth model is represented by the equation:

Where:

• represents the rate of change of the population size over time.
• is the intrinsic growth rate of the population.
• is the current population size.
• is the carrying capacity of the environment.

This equation describes how the growth rate is proportional to both the size of the population and the available resources, considering the environmental limitations (carrying capacity). As the population size approaches the carrying capacity , the growth rate slows down, leading to a sigmoid or S-shaped curve.

Therefore, the correct equation from the given options for Verhulst-Pearl Logistic Growth is:

Ex-situ conservation refers to the preservation of components of biological diversity outside their natural habitats. This approach is used to protect endangered species by removing part of the population from a threatened habitat and placing it in a new location, which can ensure better propagation and survival rates under controlled conditions. The options provided are as follows:

• Biosphere reserves: These are designated areas that promote the conservation of biodiversity, including plants, animals, and micro-organisms, in their natural environment. Therefore, this falls under in-situ conservation methods.
• National parks: These are protected areas aimed to conserve habitats and wildlife in their natural surroundings. As such, they represent an in-situ conservation strategy.
• Wildlife sanctuaries: These are areas designated for the protection of wild animal species in their natural habitat, making them a form of in-situ conservation.
• Seed banks: Seed banks involve the preservation of plant seeds to safeguard genetic diversity outside their natural environment, thereby categorizing them as an ex-situ conservation method. Seed banks play a crucial role in preventing plant extinction by storing seeds in controlled conditions where they can remain viable for extended periods.

From these options, Seed banks specifically represent ex-situ conservation because they store and maintain biological material outside its natural habitat.

The stratosphere is a layer of Earth's atmosphere situated above the troposphere and below the mesosphere. It plays a crucial role in protecting life on Earth by filtering out harmful ultraviolet (UV) radiation from the sun. The gas that is predominantly found in the stratosphere and responsible for this protection is:

• Ozone

Ozone is a form of oxygen with three atoms (O₃), distinct from the O₂ molecule we breathe. It forms the ozone layer, which effectively absorbs and scatters the ultraviolet solar radiation. This makes it critical for sustaining life and keeping ecological balance.

Thus, the correct answer to the question regarding which gas is found in the stratosphere is Ozone.

In an ecosystem, the biomass of primary consumers being greater than that of producers is a characteristic of certain environments. This situation primarily occurs in aquatic systems, such as the sea. Let's explore why this occurs:

• Productivity: In the sea, microscopic producers like phytoplankton reproduce and grow rapidly, but individual biomass remains small. Despite their rapid turnover, their standing biomass at any moment is relatively lower.
• Consumer Efficiency: Zooplankton, the primary consumers in marine ecosystems, have a high efficiency in consuming these producers. Because they have longer lifespans compared to phytoplankton, their cumulative biomass can exceed that of the producers they consume.
• Turnover Rate: The high turnover rate of phytoplankton ensures continuous availability of food for zooplankton, maintaining a higher biomass of consumers over producers.

Therefore, the ecosystem where the biomass of primary consumers is greater than that of producers is the sea.

Two closely related species can co-exist indefinitely and violate Gause’s ‘Competitive Exclusion Principle’ through a process called resource partitioning.

Gause's Principle states that two species competing for the exact resources cannot stably coexist if other ecological factors remain constant. However, species can avoid this direct competition by dividing resources and utilizing them in different ways. This strategy, known as resource partitioning, allows them to coexist without direct competition for the same resources.

Here's how resource partitioning works:

• Different Resources: Each species uses a different set of resources to reduce direct competition.
• Temporal Separation: Species utilize the same resource but at different times, avoiding overlap.
• Spatial Separation: Different species occupy separate habitats or areas to minimize direct competition.
• Morphological Adaptations: Physical adaptations can lead to different feeding techniques or preferences, allowing coexistence.

Thus, resource partitioning enables species to reduce direct competition and co-exist over a long period, overcoming the limitations of Gause’s Principle.