Christopher Joyce

First of a two-part series. Read Part 2.

Modern architecture loves glass. Glass makes interiors brighter and adds sparkle to cityscapes. But glass also kills millions of birds every year when they collide with windows. Biologists say as more glass buildings go up, more birds are dying.

The famous paintings on the walls of caves in Europe mark the beginning of figurative art and a great leap forward for human culture.

But now a novel method of determining the age of some of those cave paintings questions their provenance. Not that they're fakes — only that it might not have been modern humans who made them.

The first European cave paintings are thought to have been made over 30,000 years ago. Most depict animals and hunters. Some of the eeriest are stencils of human hands, apparently made by blowing a spray of pigment over a hand held up to a wall.

A bizarre event has drawn scientists to a beach in Oregon — a floating concrete dock from Japan has washed ashore. It had been ripped from its moorings by last year's tsunami and floated across the Pacific.

The dock is encrusted with mussels, barnacles and other marine life from Asia. Scientists are amazed these organisms survived the 14-month voyage, but they're also worried some of these organisms could become pests in U.S. waters.

Fossil-hunting scientists are coming to grips with a new discovery that could change forever how we think of dinosaurs. What they've found is that dinosaurs may well have been tortured by large, flealike bloodsucking insects.

Yes, it appears that the greatest predators that ever roamed Earth suffered just as we mammals did — and as we still do. Fleas were thought to have evolved along with mammals — they like our soft skins and a diet of warm blood.

Scientists who watch for earthquakes have discovered a big increase in the number of small quakes in the middle of the country. It's an area that's usually pretty quiet geologically.

The scientists suspect the quakes are caused by wastewater wells. They plan to discuss their findings later this month at a seismology conference, but they've shared the basics with NPR.

Bill Ellsworth, a seismologist at the U.S. Geological Survey, says new technology over the past decade has given scientists a much better feel for when the Earth shakes.