Hummingbirds are great subjects for evolutionary biologists because they are so extreme. They live at a fast pace, wings a blur, tongue darting in and out of flowers at a frenetic pace, often 15 or 20 times a second.

And, according to Alejandro Rico-Guevara at the University of Connecticut: “They’re just fascinating. They are so bold.”

Dr. Rico-Guevara, who just published in Proceedings of the Royal Society B a description of how the hummingbird’s tongue works to draw up nectar, said that when working in the middle of the forest, he has often had hummingbirds approach him. “They just come to hover right in front of your face.” He said it is as if they are asking, “Why are you here?”

Dr. Rico-Guevara could have explained that he had reasons beyond his delight in the birds, which he said were everywhere when he was growing up in Colombia.