You walk past your fish tank and suddenly notice one of your fish floating strangely near the surface or maybe even upside down. Your heart skips a beat. Is it dead? But wait its gills are still ...

Dams provide energy, water, and protection. But they also block the ancient migration paths of salmon and other fish. Fish ladders are the surprising solution — carefully engineered stair-like ...

Scientists are uncovering new clues that a cosmic explosion may have rocked Earth at the end of the last ice age. At major Clovis-era sites, researchers found shocked quartz—evidence of intense heat ...