How does biodiversity loss and habitat fragmentation affect ecosystem resilience?

• A. Reduces genetic diversity and isolates populations.
• B. Increases genetic diversity and connectivity.
• C. Has no effect on resilience.
• D. Strengthens ecosystem recovery after disturbances.

Answer: (A)

Biodiversity loss and habitat fragmentation weaken how ecosystems cope with change by reducing genetic diversity within populations and limiting movement between them. When genetic diversity is lower, populations have fewer genetic options to adapt to new pests, diseases, or climate shifts, making them more vulnerable. Fragmentation creates small, isolated patches, which cuts gene flow and increases the chances of inbreeding. This erodes adaptive capacity and can lead to local extinctions, making recovery after disturbances slower or less likely. Because resilience relies on a mix of diverse species, robust interactions, and the ability of communities to rebound, losing species diversity and breaking connectivity directly undermines that buffering capacity.

The idea that diversity would increase or that fragmentation would boost connectivity doesn't fit real-world patterns, and claims that there’s no effect or that recovery is strengthened after disturbances run opposite to what we observe in most ecosystems.