Feb 08, 2025

Exploring the world of animals that don't need oxygen to live

Siddhartha Jana

Certain species have adapted to live without oxygen, flourishing in hostile habitats such as muddy swamps and deep seas.

Source: Canva

Despite normally requiring oxygen for respiration, the little freshwater animal Hydra can transition to anaerobic respiration in low-oxygen situations.

Source: Canva

Spiny-headed worms are parasitic and live in oxygen-free intestines, collecting nutrition straight from their hosts, allowing them to thrive in unusual environments.

Source: Canva

The microscopic creature Loricifera, which lives on the deep ocean floor, breathes using hydrogen rather than oxygen and can survive in harsh environments.

Source: Wikimedia commons

Tardigrades (water bears) can survive in space and underwater because they can "pause" their body processes in harsh conditions.

Source: Canva

The salmon parasite Henneguya salminicola does not have mitochondria; instead, it takes nutrition straight from its host and survives without oxygen.

Source: Wikimedia commons

Creatures that can swallow humans whole