Why is genetic homozygosity dangerous to the nearly extinct species?

Genetic homozygosity poses a danger to nearly extinct species because it reduces genetic diversity, which is crucial for a population's adaptability and resilience to environmental changes, diseases, and other threats. When individuals are genetically similar, they may share harmful mutations and have a decreased ability to adapt to new challenges. This lack of diversity can lead to inbreeding depression, resulting in reduced fertility, lower survival rates, and an overall decline in population health. Consequently, homozygosity can accelerate the extinction risk for already vulnerable species.