Hagfish are slime-producing marine fish with a skull but no vertebral column, making them the only known living animal with rudimentary vertebrae.
Hagfish and lampreys are jawless vertebrates that are related to jawed vertebrates and similar to those found around 300 million years ago.
They are scavengers and predators that feed on dead or dying fish and also attack injured or weakened live fish.
They produce a lot of slime, which is a thick, milky mesh of proteins that can entangle and make predators difficult to swallow.
Despite their diverse nature, they are a fascinating yet understudied species that exhibit unique adaptations to survive in harsh ocean environments.
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