Many butterflies and moths have colors that show a metallic sheen. That sheen occurs because the refracting material in their wings and bodies is spread out in layers precisely as thin as the wavelengths of the light they refract.

Workers expanding a highway in 2010 found fossils of 80 huge whales in desert sandstones in Chile, prompting questions of how they died and why they were so well preserved.

Cuttlefish are mollusks that look somewhat like squid. They have an internal, hard, supportive structure with soft organs around and inside it. This resilient "cuttlebone" is made of cleverly woven strands of a biochemical material called chitin and mixed with a hard biomineral called aragonite.

Cambrian rock layers contain many strange animal fossils, and very few fossils appear in layers below them. Called the "Cambrian explosion of life," the creatures in these layers come from all the major groups of animals alive today (including fish, which represent the vertebrates), plus many more that later became extinct.

A new fossil was uncovered in China with bird bones in its ribcage—right where its stomach must have been. Researchers consider it to be a predatory dinosaur that ate an adult bird just before it died. But was it really a dinosaur?