Snakes control blood flow in their 'spectacles'

[Martijn]

Snakes can control blood flow in their "spectacles", scientists have found.

The animals are known for their lack of eyelids, and instead have a transparent scale covering their eyes for protection.
These "spectacles" contain blood vessels, and researchers investigated how this arrangement does not obscure vision.
They found blood flow changed when the snakes perceived a threat, allowing for optimal vision.

Bron/lees verder: BBC Nature