extinctspecies

Extinct species are organisms that no longer have any living individuals anywhere on Earth. Extinction denotes the end of a species’ lineages and is considered permanent in its taxonomic sense. In addition to global extinction, some species persist in parts of their range but are locally extinct (extirpated) in others, or survive only in captivity or cultivation as extinct in the wild. Extinction can occur gradually over long periods or via rapid events such as disasters or mass die-offs, and the pace varies across taxa and eras.

Causes of extinction range from natural ecological and environmental changes to human-driven pressures. Natural factors include climate shifts, volcanic activity, and asteroid impacts. In recent times, human activities have accelerated losses through habitat destruction, overexploitation, pollution, introduction of invasive species, and climate change. Small populations face higher risks from demographic fluctuations, genetic inbreeding, and environmental catastrophes. Modern analyses indicate that current extinction rates exceed the long-term background rate, underscoring an ongoing biodiversity crisis linked to human influence.

Notable extinct species include the dodo (Raphus cucullatus), the passenger pigeon (Ectopistes migratorius), the woolly mammoth (Mammuthus primigenius), the Steller’s sea cow (Hydrodamalis gigas), the Tasmanian tiger (Thylacinus cynocephalus), and various moa species of New Zealand. The loss of species can alter ecosystem processes such as seed dispersal, pollination, and trophic dynamics, with cascading effects on communities and habitats.

Study methods involve fossils, subfossils, radiometric dating, and ancient DNA analysis to reconstruct past ecologies. Conservation biology uses these insights to prioritize protection, manage captive populations, and preserve genetic resources in seed banks and other repositories to reduce future losses.