How do animals detect food texture?
Food texture such as hardness play a very important role in regulating food preferences in animals. In the fruit fly, food texture sensation depends on a mechanosensory neuron (green) located in its tongue (red).
The forces produced during food chewing activate this neuron, which in turn transmits food texture information to the brain. The green shows the sensory neuron responsible for detecting food texture, and the red shows the spring-like structures of the fly tongue.