31 Years NEET Previous Year Questions: Biodiversity & Conservation Free

Zoos and botanical gardens: These are examples of ex-situ conservation. They involve the preservation of species outside their natural habitats. Here, animals and plants are provided with a controlled environment that mimics their natural surroundings as much as possible. These facilities play a crucial role in breeding programs, research, public education, and reintroducing species into the wild when conditions permit.

• Zoos: Focus on preserving and breeding animal species.
• Botanical gardens: Aim to conserve diverse plant species, including rare and endangered ones.

A. The Evil Quartet - III. Causes of biodiversity losses:

• The "Evil Quartet" refers to four major causes of biodiversity loss: habitat destruction, overexploitation, invasive species, and co-extinctions.
• These factors collectively threaten the survival of various species and ecosystems globally.

B. Ex situ conservation - I. Cryopreservation:

• Ex situ conservation involves conserving biodiversity outside their natural habitats, such as in seed banks, botanical gardens, or through cryopreservation.
• Cryopreservation is a technique used for freezing and storing genetic material (like seeds or embryos) at very low temperatures for future use.

C. Lantana camara - II. Alien species invasion:

• Lantana camara is an invasive alien species that disrupts native ecosystems by competing with native flora and causing ecological imbalances.
• Alien species invasions are a major contributor to biodiversity loss and ecosystem degradation.
• The environmental damage caused and threat posed to our native species by invasive weed species like carrot grass (Parthenium), Lantana and water hyacinth (Eicchornia).

D. Dodo - IV. Extinction:

• The Dodo is an example of a species that has gone extinct due to human activities such as hunting and habitat destruction.
• Extinction is the complete loss of a species, often driven by factors like overexploitation, invasive species, and habitat destruction.

To match the correct individual with their contribution or hypothesis, let's review each person listed along with the contributions mentioned:
Robert May is best known for his pioneering work in theoretical ecology, particularly in the areas of population dynamics and stability in ecological communities. However, none of the choices directly mention these specific contributions. Among the options, the closest (though indirect) could be his theoretical work that touch upon aspects like species diversity estimations.
Alexander von Humboldt, known for his extensive work in biogeography, made critical observations on the geographic distributions of species. His work best correlates with the "Species-Area relationship," which describes how the number of species increases with the area surveyed.
Paul Ehrlich is famous for his work on population studies and environmental issues facing humanity. His statement about the planet's carrying capacity and potential biodiversity loss is widely known. The "Global species diversity at about 7 million" might closely relate to his biodiversity and population studies, though it's not his primary known work.
David Tilman is well-acclaimed for his experimental work on biodiversity and ecosystem productivity. The "Long term ecosystem experiment using outdoor plots" directly correlates with his experimental approach to studying the relationship between biodiversity and ecosystem functioning using field experiments.

Given these associations:
A (Robert May) might best fit with "Global species diversity at about 7 million" (III) though it's a rough fit.
B (Alexander von Humboldt) correlating with "Species-Area relationship" (I) is a much clearer connection.
C (Paul Ehrlich) and the "Global species diversity at about 7 million" (II) matches if we consider his general scope in biodiversity and population dynamics.
D (David Tilman) with "Long term ecosystem experiment using out door plots" (II) is an exact match for his field of work.

Looking at the options provided,
Option B: A-III, B-I, C-IV, D-II
This option aligns correctly as per the reasoning.
Therefore, the correct answer is Option B.
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importance of species diversity to the ecosystem

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The major causes of biodiversity loss primarily involve the negative impacts human activities have on ecosystems, with some of the most critical factors being:
Overexploitation: This refers to the unsustainable use of wildlife and plant species for food, medicine, or other human needs which leads to the reduction in numbers of these species to dangerously low levels.
Co-extinction: This occurs when the extinction of one species leads to the extinction of another species that depend on it for survival, such as a predator and its prey or a plant and its pollinator.
Habitat loss and fragmentation: This is the process whereby a large, continuous area of habitat is both reduced in area and divided into smaller, more isolated fragments due to activities like logging, agriculture, and urban development. This disrupts ecosystems and decreases the viability of populations.

Regarding the listed options:

• Mutation: While mutations (genetic changes) are not generally a direct cause of biodiversity loss, they can influence the adaptability and survival of species. However, they are not typically regarded as a major driver of biodiversity loss.
• Migration: Normal species migrations are natural phenomena and not a direct cause of biodiversity loss. Instead, barriers to migration created by human activities can contribute to biodiversity loss by preventing species from reaching essential habitats for their survival and reproduction.

Therefore, the correct option that lists recognized major causes of biodiversity loss is: Option D: A, B, and D only (Overexploitation, Co-extinction, and Habitat loss and fragmentation).