Biology – Conservation | e-Consult

Extinction is a complex process driven by a variety of factors, often acting in concert. Climate change, competition, human hunting, habitat degradation, and loss of habitat all contribute to population decline and, ultimately, extinction. These factors are often interconnected, exacerbating the negative impacts.

Climate Change: Alterations in global temperature and precipitation patterns can exceed a species' physiological tolerance. Species may be unable to adapt quickly enough, leading to reduced reproductive success, altered migration routes, and mismatches in predator-prey relationships. For example, rising ocean temperatures cause coral bleaching, destroying habitats for countless marine species. Changes in rainfall can lead to droughts or floods, impacting plant growth and food availability for herbivores, ultimately affecting the entire food chain. Species with limited dispersal abilities are particularly vulnerable.

Competition: When populations of different species occupy the same niche, they compete for limited resources such as food, water, and space. Increased competition can lead to the decline of one or both species. For example, the introduction of invasive species often outcompetes native species, pushing them towards extinction. This is because invasive species are often better adapted to the new environment and have fewer natural predators or diseases.

Hunting by Humans: Historically, overhunting has been a major driver of extinction. Humans have hunted species to extinction for food, fur, or sport. Even today, poaching remains a significant threat to many species, particularly those with low reproductive rates or specialized habitat requirements. The decline of the Dodo bird is a classic example of extinction caused by human hunting.

Habitat Degradation and Loss: This is arguably the most significant threat to biodiversity today. Habitat loss occurs when natural habitats are destroyed or fragmented due to human activities such as agriculture, urbanization, and deforestation. This reduces the amount of suitable habitat available for species to live and reproduce. Habitat fragmentation isolates populations, reducing genetic diversity and making them more vulnerable to environmental changes. For example, deforestation in the Amazon rainforest is driving many species towards extinction by destroying their homes and food sources.

Interconnectedness: These factors are often interconnected. Climate change can exacerbate habitat loss by altering vegetation patterns. Increased competition can be intensified by habitat fragmentation, as species are forced into smaller areas with limited resources. Human hunting can further reduce population sizes, making species more vulnerable to climate change and habitat loss. The combined effect of these factors can push a population beyond its ability to recover, leading to extinction. Conservation efforts must address all of these threats simultaneously to be effective.