3. Biodiversity Makes Ecosystems More Resilient

Biodiversity means variety in living systems. It includes genetic diversity within a species, species diversity within a community, and ecosystem diversity across a region. A meadow with many grasses, flowers, insects, birds, and decomposers has more biodiversity than a field planted with one crop.

Biodiversity matters because species do jobs. Some pollinate, some decompose, some filter water, some hold soil in place, and some control prey populations. When several species can perform similar jobs, the ecosystem has backup. If one species suffers from a disease or heat wave, another may keep the function going.

This is why a diverse ecosystem is often more resilient, meaning it can recover after stress. Low-diversity systems can be productive, but they are vulnerable. A single pest or drought can damage a monoculture because nearly every plant responds the same way.

The GED® may ask why biodiversity loss matters to humans. The answer is not only "animals are nice." Biodiversity supports food production, clean water, soil formation, pollination, medicines, flood control, and climate regulation.