extinktioa

Extinktioa is the permanent disappearance of all individuals of a taxon, such as a species or subspecies, resulting in the end of that group. In scientific use, extinction means there are no living members left anywhere on Earth. The term can also be used in cultural contexts to describe the loss of languages, traditions, or practices, though this usage is metaphorical.

In biology, extinction is contrasted with extirpation, the local disappearance of a population without global end, and with ongoing processes of speciation and diversification. Entirely extinct groups are typically known from the fossil record or from historical accounts.

Most extinctions occur through a combination of factors including habitat destruction, climate change, overexploitation, invasive species, pollution, and disease. Human activity has accelerated extinction rates, particularly in recent centuries, contributing to loss of biodiversity and disruption of ecosystems.

Detection relies on field surveys, taxonomic studies, and paleontological data. Conservation status schemes such as the IUCN Red List classify species with categories like Endangered, Vulnerable, and Extinct when appropriate. An extinct designation is given when exhaustive surveys fail to locate individuals.

Effects of extinction extend beyond the loss of individual species; they can alter ecosystem structure, functions, and resilience. Conservation aims to prevent extinctions through habitat protection, restoration, captive breeding, reintroduction, controlled use, and international policy measures.

Examples commonly cited include the Dodo (Raphus cucullatus), the Passenger Pigeon (Ectopistes migratorius), and the Tasmanian Tiger (Thylacinus cynocephalus). These cases illustrate how human activities and ecological change can push lineages toward extinction and how conservation science seeks to prevent such losses.