Biodiversity & Environmental Issues Test - 18

Genetic variation is advantageous to a population because it enables some individuals to adapt to the environment while maintaining the survival of the population.
Speciation occurs from standing genetic variation when reproductive isolation between 2 or more populations evolves from alleles already present within the common ancestral population, rather than from new mutations. This seasonal difference contributes to strong (although still incomplete) reproductive isolation.
Mutations are changes to an organism 's DNA and are an important driver of diversity in populations. Species evolve because of the accumulation of mutations that occur over time.
This mutation has introduce a new allele into the population that increases genetic variation and may be passed on to the next generation.

 

• Paul Ehrlich, a Stanford ecologist gave the ‘Rivet popper hypothesis ’.
• In this hypothesis, he considered species as a rivet.
• This hypothesis provides a perspective on what might happen if a few species of the planet are extinct.

The Deccan Plateau is famous for its biodiversity. The area is home to an exotic range of flora and fauna. Two of India ’s most significant elephant conservation regions, the Anamalais-Nelliampathis and the Nilgiris-Eastern Ghats are located in this area.

Tropical latitudes receive more solar energy than temperate regions, which leads to high productivity and high species diversity.
Tropical regions have less seasonal variations and have a more or less constant environment. This promotes the niche specialization and thus, high species richness.
Temperate regions were subjected to glaciations during the ice age, while tropical regions remained undisturbed which led to an increase in the species diversity in this region.
 

Threats to Biodiversity:
There are several threats to biodiversity, including:
Habitat loss:
- Destruction of natural habitats due to human activities, such as deforestation, urbanization, and conversion of land for agriculture or infrastructure development.
- Fragmentation of habitats, which reduces the availability of suitable living spaces for many species.
- Pollution and contamination of ecosystems, which can render habitats uninhabitable for various organisms.
Over exploitation:
- Over-harvesting of species for economic purposes, such as hunting, fishing, and logging.
- Illegal wildlife trade, which leads to the unsustainable removal of numerous species from their natural habitats.
- Unsustainable fishing practices, including overfishing and destructive fishing methods, which deplete fish populations and disrupt marine ecosystems.
Intensive agriculture:
- Conversion of natural landscapes into agricultural areas, resulting in the loss of biodiversity-rich habitats.
- Use of chemical fertilizers, pesticides, and herbicides, which can contaminate ecosystems and harm non-target species.
- Monoculture practices, where large areas are dominated by a single crop, leading to a loss of biodiversity and increased vulnerability to pests and diseases.
All of these:
- All the factors mentioned above (habitat loss, over exploitation, and intensive agriculture) collectively contribute to the threats faced by biodiversity.
- The combination of these threats exacerbates the loss of species, disrupts ecosystems, and reduces overall biodiversity.
In conclusion, the threats to biodiversity are multifaceted and interconnected. Habitat loss, over exploitation, and intensive agriculture all play significant roles in the decline of biodiversity. Addressing these threats requires a holistic approach that includes conservation efforts, sustainable resource management, and policy interventions to protect and restore habitats, regulate exploitation, and promote sustainable agricultural practices.

The disappearance of cheetah from India and its exist- ence in other parts of the world is an example of expirtation.
Cheetahs face habitat loss driven by conversion of wilderness areas into managed land dedicated to agriculture or livestock. People will then sometimes kill cheetahs if they perceive the animals as a threat to their livestock, even though cheetahs rarely take domesticated animals.

The solar energy contributes to higher productivity in the tropical regions. This leads to more food production that in turn leads to specialization in the niche and leads to a greater diversification of species.

• An ecosystem consists of biotic and abiotic components that interact within a system.
• The components are linked together with various nutrient cycles and energy flows.
• The ecosystem might become unsafe and will collapse if the key species that drive major ecosystem functions are lost.

A  vulnerable species  is a  species  of  animals  or  plants  which are likely to become  endangered  unless something changes. Something has to be done to remove the things that are harmful to their survival, and their rate of  reproduction  needs to increase.

Tropical environments have remained undisturbed for millions of years that are a long evolutionary time. Due to such environmental consistency, they promote specialization in the niche and lead to a greater diversification of species.