What does extinction signify?

Extinction signifies that a species no longer exists anywhere on Earth, marking the complete disappearance of that species from all habitats and environments. When a species goes extinct, it means that there are no surviving individuals left, and it cannot be found in wild or captive populations. This concept of extinction is critical in wildlife ecology as it has profound implications for biodiversity, ecosystem health, and conservation efforts. Understanding extinction helps in recognizing the urgency of conservation strategies to protect threatened species and prevent further loss of biodiversity.

The other choices, while related to the status of species, do not accurately capture the definition of extinction itself. A species thriving in its habitat indicates robust population levels and successful reproduction, while a species existing only in captivity refers to those that have no wild populations left but can still be found in zoos or conservation programs. A species on the verge of extinction refers to those that are critically endangered but have not yet been lost entirely, making it a separate situation from extinction.