concepts of extinction

Extinction occurs when a species or group of organisms disappears entirely from Earth, meaning no individuals remain alive. It can happen when environmental conditions change, making survival impossible, or when threats like habitat destruction, pollution, or invasive species reduce their numbers significantly. Extinction is a natural part of evolution, but human activities have accelerated it dramatically. Once extinct, a species cannot be brought back, highlighting the importance of conservation efforts to protect endangered species before they vanish entirely.