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How do lice stay attached to feathers and hair?

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human head louse — louse Human head louse (*Pediculus humanus*).

Lice have evolved specialized physical adaptations to remain attached to their hosts. Their bodies are flattened dorsoventrally, which allows them to lie closely against feathers or hairs for secure attachment.1

The legs of lice are well developed and equipped with claws to facilitate this grip:
* Avian lice: These typically possess two claws to grasp feathers.1
* Mammalian lice: Some species have a single claw, while others, specifically the Anoplura (sucking lice), feature a single claw opposed to a tibial process, which functions as a specialized hair-clasping organ.1

Additionally, lice are behaviorally adapted to maintain this contact. They are attracted to body heat and repelled by light, which encourages them to remain within the warmth and darkness of the host's plumage or pelage. They are also sensitive to the specific characteristics of feathers and hairs, which helps them orient themselves on the host's body.2