Final answer:
The primary danger of allowing an encroachment is the destruction and disruption of natural habitats, as it can lead to the transmission of pathogens and negatively impact human health.
Step-by-step explanation:
When it comes to allowing encroachment, the primary danger is the potential destruction and disruption of natural habitats. This can occur through residential development, mining, farming, or logging activities, which bring humans into contact with previously unknown microorganisms that can be pathogenic to people. Additionally, uncontrolled urbanization can lead to overcrowded areas with poor sanitation, facilitating the transmission of pathogens. Ultimately, encroachment can have negative effects on both the environment and human health.