Manatees use thousands of specialized hairs across their entire bodies to "see" their surroundings through touch.

Manatees possess approximately 3,000 to 5,000 specialized tactile hairs known as vibrissae. While most mammals restrict these hairs to the facial region, manatees are unique for having them distributed across their entire bodies. Research conducted by Dr. Diana Reiss and colleagues at the Mote Marine Laboratory has shown that these hairs are connected to a massive network of nerve fibers.Each individual hair is follicle-bound and serves as a sophisticated sensory organ. These hairs allow the manatee to detect hydrodynamic stimuli, which are subtle movements or pressure changes in the water column. This ability is so precise that they can sense the movement of a single fish from several meters away or detect the texture of seagrass before eating it.The manatee's brain is specially adapted to process this tactile information. A significant portion of their somatosensory cortex is dedicated to interpreting signals from these body hairs. This sensory adaptation is essential for survival in the sediment-heavy, low-visibility coastal waters and rivers of Florida and the Caribbean.Evolutionarily, this system functions similarly to the lateral line found in fish. It provides the manatee with a three-dimensional map of its environment without needing sight. This explains how these large marine mammals successfully navigate complex underwater structures and avoid obstacles during nighttime or in muddy estuaries.