Horses are known to use loud calls, called whinnies or neighs, to communicate during social activities such as greeting other horses or showing excitement. For many years, the exact process behind this sound remained elusive to researchers studying animal communication. A recent scientific study published in 2024 examined how horses produce this vocal phenomenon using modern imaging tools. The research was carried out by an international team working in European research centers that focus on animal biology. The study aimed to explain why horses, despite being large animals, can produce both low and high sounds at the same time. Understanding this behavior is important because vocal signals play a key role in horse social life and emotional expression.

The researchers used innovative methods, including tiny cameras placed inside the nasal passages, detailed scans, and airflow tests on preserved voice boxes. These tests showed that a horse whinny is created through two sound mechanisms working together. The low sound comes from vibrating tissues in the voice box, while the high sound is produced by a whistle formed when a small opening above the tissues narrows. Experts noted that this discovery is significant because horses are the largest known mammals to create a whistle inside the voice box. This ability may help horses send more detailed messages during social contact, which adds to the complexity of animal communication. The findings also raise new questions about how this vocal skill developed and whether it offers advantages in the wild or in domesticated settings.