How do lice cling? - briefly
Lice secure themselves to hair by using six hooked claws on each leg to grasp the shaft, and by secreting a proteinaceous cement from their salivary glands that hardens to lock the egg or adult in place. This dual mechanism ensures a firm attachment despite movement or grooming.
How do lice cling? - in detail
Lice remain attached to their hosts through a combination of specialized anatomical structures and biochemical adaptations.
The anterior legs end in robust, sharply curved tarsal claws that interlock with the cuticle ridges of hair shafts. These claws fit into the triangular or oval cross‑section of each strand, creating a mechanical lock that resists displacement by friction or movement.
The middle and posterior legs possess smaller, hook‑like claws that assist in stabilizing the insect on the hair surface and in maneuvering between strands.
A thin layer of waxy secretion coats the ventral surface of the louse’s body. This hydrophobic film reduces slippage on the hair shaft and helps maintain a seal against the host’s skin, preventing desiccation and enhancing grip.
Sensory setae on the legs detect the texture and angle of the hair, allowing the insect to adjust claw pressure continuously.
Key points of attachment:
- Curved tarsal claws on the front legs engage hair cuticle ridges.
- Secondary claws on the other legs provide additional anchorage.
- Waxy cuticular coating increases friction and prevents water loss.
- Sensory hairs guide precise positioning and force modulation.
Together, these features enable lice to cling securely for the duration of their life cycle, despite host grooming or environmental disturbances.