What is a significant risk of decreased genetic diversity in a species?

Decreased genetic diversity in a species poses a significant risk because it can lead to higher chances of extinction. Genetic diversity is essential for the health and resilience of populations; it provides a wider range of traits that can enhance a species' ability to adapt to changing environments, recover from stresses such as disease or climate change, and respond to natural selection.

When genetic diversity is low, a population becomes more homogenous, meaning the individuals are more similar genetically. This can limit the overall adaptability of the population, making it more vulnerable to environmental changes or threats. A lack of variation means that if a disease emerges or if the environment changes rapidly, the entire population may be susceptible to those challenges, potentially leading to population decline and increased extinction risk.

Moreover, low genetic diversity can also lead to inbreeding, which often results in a higher incidence of genetic disorders and reduced fertility, further exacerbating the vulnerabilities of the population. Hence, the correct answer highlights a crucial concern in conservation biology, emphasizing the importance of maintaining genetic diversity for the survival of species.