What type of ecosystem indicator signifies biodiversity?

The presence of a diverse range of wildlife is a strong indicator of biodiversity within an ecosystem. Biodiversity refers to the variety of life forms in a particular habitat or ecosystem, encompassing differences in species, genetic variations, and ecological roles. A high diversity of wildlife suggests a healthy and resilient ecosystem, as it typically indicates that various species are thriving and that ecological interactions (such as predation, competition, and symbiosis) are functioning effectively.

In contrast, the other options indicate aspects of an ecosystem that do not reflect its overall health or biodiversity. For example, the presence of a single species may suggest dominance or a lack of competition, which could lead to an unhealthy ecosystem. Similarly, an absence of natural predators may lead to overpopulation of certain species, destabilizing the ecosystem. Lastly, a high density of invasive plants usually signifies a disruption of the native ecosystems and can lead to reduced biodiversity, as invasive species often outcompete native species for resources. Therefore, diversity of wildlife is the most direct and positive indicator of biodiversity.