Equine

Whistle while you whinny: researchers identify two sounds straight from the horse's mouth

• Horses produce whinny via simultaneous low-frequency nickering and high-pitched whistle. • This biphonation enables complex social messages across distances and emotional states.

Horses with over 30 minutes of REM sleep show better persistence in learning tasks

• Horses with ≥30 minutes REM sleep daily outperform peers in field learning tasks. • Short REM periods reduce perseverance and performance during demanding training. • New field‑a