NPR在线收听:'Butterfly Tongues' Are More Ancient Than Flowers, Fossil Study Finds



We usually see butterflies hanging out around flowers and drinking nectar, but scientists have made the startling discovery that there were butterflies long before there were many flowers. NPR's Rebecca Hersher reports that scientists found this out by studying fossilized bits of butterfly from millions of years ago.

REBECCA HERSHER, BYLINE: Butterflies are really delicate creatures, so they don't preserve well, which means there aren't that many complete fossils. But a team looking at soil from Germany stumbled upon fossils of tiny butterfly scales. Scales give butterfly wings their colors.

TIMO VAN ELDIJK: If you, like, touch the wing of a butterfly, you will very often see that the color tends to fade, and that's actually the scales coming off the wing.

HERSHER: This is Timo van Eldijk over Skype. He's a master's student in the Netherlands and one of the authors of a new study published today in the journal Science Advances. He says these are the oldest butterfly fossils ever discovered, from the Jurassic period about 200 million years ago. But the most exciting thing was what van Eldijk saw when he looked at the scales under a microscope. Some of them were hollow, and that can only mean one thing - that prehistoric butterflies had proboscises. That's basically a butterfly's trunk.

ELDIJK: If you find the hollow scales, you know that this innovation of the proboscis must have already occurred before that.

HERSHER: There's no way to have hollow scales if you don't have a proboscis.

ELDIJK: No, no.

HERSHER: But here's what's weird about that - modern butterflies only use their proboscises to suck up nectar from deep inside flowers.

ELDIJK: The traditional idea is always butterfly tongue is your standard adaptation that you have when you feed on flowers, right?

HERSHER: But that can't be right because the ancient butterflies with the hollows scales and the proboscises were flying around long before there were any flowering plants on Earth. So what were butterflies using their tongues for - hard to know. They might have still used them to eat, maybe droplets on the surface of cones instead of flower nectar. Or maybe the tongue helped them stay hydrated. The Jurassic, after all, was a pretty dry time. Rebecca Hersher, NPR News.

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