Thyroid Function in Fish

The role of thyroid hormones in fish - especially critical for metamorphosis in flatfish, salmon smoltification, and eel life-history transitions.

System: Endocrine Level: Advanced Discipline: Endocrinology

📖 Overview

Thyroid hormones drive some of the most dramatic transitions in fish biology. Flatfish larvae undergo eye migration under thyroid hormone control. Salmon smoltification - the freshwater to saltwater physiological switch - is thyroid-mediated. Eel silvering (from freshwater yellow eel to marine silver eel) is another thyroid-driven metamorphosis.

✨ Fun Fact

The eye migration of flatfish - one of the strangest developmental transitions in vertebrates - is controlled by thyroid hormone. Block thyroid function experimentally and the eye stays put.