Have you ever seen a hummingbird hawk moth? When people encounter this moth for the first time, they are usually intrigued: Looking like a cross between a butterfly and a bird - hence the name - this animal has the amazing ability to hover like a helicopter for long periods.They discovered that the animals use their sense of sight to move and, if necessary, correct the movement of the proboscis using visual feedback on the way to the nectary, much like we humans do when grasping something with our hands.

To demonstrate that this appendage control also occurs in insects, the researchers conducted sophisticated behavioural experiments in which hummingbird hawk moths were recorded with high-speed cameras as they approached artificial flowers. This way they could determine the exact positions of the moths' bodies, heads and proboscis with high temporal resolution while the animals were searching for nectar. To control the rough positioning of the proboscis in the flower, the animals move their entire bodies in flight, while the smaller movements of the proboscis itself are used to precisely target the flower pattern.

The fact that the moths use visual feedback for the fine control of their proboscis was somewhat surprising, because such a real-time coordination between what they see and the movement of their proboscis is computationally complex. Insects have a comparatively simple nervous system with less than one million nerve cells, compared to nearly 90 billion in the human brain. These small brains and their efficient way of working are also great models for applied research, for example in robotics. They can learn a lot from hummingbird hawk moths.