Question

List any three major causes of loss of biodiversity.

Discuss any three major causes of loss of biodiversity.

Discuss any four causes for the loss of biodiversity.

Answer 1

1. Habitat loss and fragmentation - The most significant factor contributing to the extinction of both plants and animals is the destruction of their habitats. Human activities that fragment large habitats into smaller pieces have a detrimental impact, particularly affecting mammals and birds that rely on expansive territories, as well as animals with migratory habits. This results in a decline in their populations.
2. Over-exploitation - Humans rely on nature for food and shelter, but greed often leads to the degradation and extinction of natural resources.
3. Co-extinction - When a species goes extinct, the plant and animal species linked to it also face inevitable extinction. For instance, in the scenario of a co-evolved plant pollinator, the extinction of one species inevitably results in the extinction of the other.

Answer 2

1. Loss of habitat or habitat alteration: A habitat is a place in which an organism lives. Habitats are an important component of an ecosystem. Loss of habitat is one of the greatest threats to biodiversity. Habitat loss is directly linked to human-induced pressures on land. Assemblages of species and their interactions with the ecosystems are critical for not only saving the species but also for their successful future evolution. In the event of alterations, either within species groups, or within the environment, entire ecosystem can begin to change. Alterations to ecosystems are a critical factor contributing to species and habitat loss. Habitat loss and degradation have affected 89% of all threatened birds, 83% of mammals, and 91 % of all threatened plants assessed globally. The main causes of habitat loss are agricultural activities, mining, development of human settlements, industry, etc.
2. Overharvesting: Overharvesting, i.e., overhunting, overfishing, or over-collecting a species, can quickly lead to its decline. Changing human consumption patterns is often cited as the key reason for the unsustainable exploitation of natural resources.
3. Introduction of alien species or invasive species: The introduction of exotic species that replace native and local species is cited as the second largest cause of biodiversity loss. Alien invasive species replace and often result in the extinction of the native species. The annual economic damage caused by invasive plant and animal species is very high.
4. Pollution: Biological systems respond slowly to changes in their surrounding environment. Pollution and contamination cause irreversible damage to the species.
5. Global climate change: Because many types of plants and animals have specific habitat requirements, climate change can cause disastrous loss to the species. A slight drop or rise in average rainfall can translate into large seasonal changes. Species may be harmed or disturbed by these changes. Both climate variability and climate change cause biodiversity loss. Species and populations may be lost permanently if they are not provided with enough time to adapt to changing climatic conditions.