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Earth's shadow and full moon rising via Birgit Boden.

When can you see Earth’s shadow?

You can see it any clear evening …

A rare fossil find from Messel Pit in Germany. See the annotated image below. Image via Springer Heidelberg/ Alpha Galileo.

Snake eats lizard eats beetle

Scientists have discovered a 48-million-year-old fossil food chain in Germany. It’s a snake with a lizard in its stomach, which in turn had eaten a beetle.

Canela (left) and Blanquita (right) don’t need symbols to express their opinions. Image credit: Dominique Brand.

How to ask a horse what it wants

Do you want a blanket? Norwegian researchers recently described how they trained horses to use symbols to answer that question.

Hermit crab colonised by zoanthid. Image via Robinson ROV-ERC

Microplastics found in deep-sea animals

Scientists were astonished to discover tiny bits of plastic inside the bodies of animals in the deep ocean.

Jim Grant caught this fogbow over Sunset Cliffs in San Diego. He wrote: "The skies were sunny and clear, and then the fog rolled in, and with it this beautiful fogbow."

What is a fogbow?

Fogbows are rainbows’ cousins – made in much the same process – but with the small water droplets inside a fog instead of larger raindrops.

A comet may have hit Earth 56 million years ago, leaving behind telltale glassy spheres in sediment cores. Image and caption via Science.

Comet strike after dinosaur extinction?

An extraterrestrial impact likely caused the dinosaur extinction 65 million years ago. Did a comet strike 10 million years later cause a global warming?

Donnehue's Cave in Indiana. Image Credit: Sam Frushour.

Clues to ancient earthquakes in caves

Stalagmites on the floors of caves in southern Indiana contain evidence of past earthquakes, scientists say.

Autumn 2016 in the Colorado Rocky Mountains. Photo via Jessi Leigh Photography.  Thanks Jessi!

Why do leaves change color in fall?

In the fall, the leaves of some trees turn yellow, orange or red. The bright colors are wonderful to behold. But do they have some hidden purpose?


Are we in a sixth mass extinction?

This short video puts modern extinctions in context by comparing them with Earth’s 5 previous mass extinctions.

Great white shark and bluefin tuna, at Monterey Bay Aquarium. Courtesy of Niall Kennedy via Flickr.com

Shark and tuna convergent evolution

Lamnid sharks and tuna have similar physical traits that make them top ocean predators. But, a new study says, they took very different evolutionary paths.