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Jewel wings fly around like little helicopters until they see preys(猎物），usually smaller flying insects,"said Bellido, a biologist at the University of Minnesota."Then they dash at their meals in a burst of speed."

You might mistake jewel wings for their cousins, dragonflies. New research shows that these two insects share something more significant than their appearance, however. In a paper published in Current Biology, Dr. Bellido and the dragonfly colleagues reveal that the neural(神经的）systems behind jewel wings' vision are shared with dragonflies, with whom they have a common ancestor that lived before dinosaurs. But over the centuries, this brain wiring has adapted itself in different ways in each creature, enabling sharply different hunting strategies.

Jewel wings' behavior involves attacking what's directly in front of them, the team found. But recordings made in the lab by Dr. Gonzalez and her colleagues confirmed that dragonflies rise up in a straight line to seize unsuspecting insects from below. Researchers are particularly interested in the

neurons(神经元）that send visual information to the wings.

To look closer at the neurons linking vision and flight, the researchers equipped jewel wings with sensors and showed them a video of a moving dot, comparing it with earlier dragonfly research. When a neuron fired, a popping sound filled the researchers' ears, allowing them to tell exactly which

movements-left, right, up, down or some combination-each neuron responded to. Jewel wings best see what's right in front of them, they found, while dragonflies' clearest vision is just above them.

The team was interested to find that while jewel wings' neurons didn't always respond like those in dragonflies, the number of neurons and organization were similar. That suggests that the system that conveys this information from the eyes to the wing muscles did not evolve recently, but has roots that are millions of years older than the oldest dinosaurs. And that ancient common ancestor likely had already developed remarkable speed in both vision and flight. Then, in the following years, the system has evolved to suit individual insect species.

This shared neural system may be more than 250 million years old, but it is also flexible enough to transform itself to meet the needs of a variety of creatures in different eras and environments, the findings suggest.