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How do bugs cling onto things without falling off? – Carmen, 7, Washington state

May 8, 2025 melissamayer

Dear Carmen,

Right now, there’s a fly walking on the window in my office. I asked my friend Rich Zack how it does that. He’s an insect scientist at Washington State University.

It turns out my window isn’t as smooth as it looks. If we zoomed in on the glass, we’d see bumps and dips. It’s kind of like a rock face or a climbing wall.

“Surfaces look pretty smooth,” Zack said. “But if you get really, really close, you see there are all kinds of little indentations and crevasses. Even a pane of glass is not perfectly smooth. It’s got little nicks and … » More …

Why do all insects have six legs? – Charlie, 10, Ohio

July 13, 2023 melissamayer

Dear Charlie,

There are about 40 kinds of cats out there—like me. There’s only one kind of human on Earth now. But there are more than a million kinds of insects. That’s just the insect species we know about.

Every single one of those insects has six legs.

I talked about why that is with my friend Allan Felsot. He’s an insect scientist at Washington State University.

He told me there must be some evolutionary reason insects have six legs—like better stability when walking.

“In biology, every ‘why’ question has the same answer,” Felsot said. “Things are the way they are because of adaptations that have allowed organisms to live longer.”