When the top spotty fish in a tank disappears, the runner-up turns aggressive within minutes, rushing and nipping rivals ...

Remove the top male spotty fish and, within minutes, the next-in-line female morphs into the tank s new tyrant charging and nipping rivals while her body quietly begins a weeks-long transition to male ...

Fossils offer a glimpse into Earth's ancient life, revealing the origins and evolution of complex organisms. Discoveries like ...

At Mission Science Workshop, San Francisco kids take apart whale skeletons, and use power tools and play with snakes — for ...

One of the highlights of this bleak period in US history, known so far as 2025, is the generous cleavage of Lauren Sánchez, ...

Key Takeaways on the First Mammal According to most experts, the first mammal was Morganucodon, a small, shrew-like rodent that appeared during the Jurassic Period, approximately 200 million years ...

Sushi options in San Francisco are abundant. There are casual joints with novel-length sushi menus, neighborhood staples that go above and beyond, and extravagant omakase counters perfect for big-deal ...

The river roars in the heat of the summer. The water is clear and cool, and a respite from the high sun. An angler leans back ...

In 2015, two members of the Blue Beach Fossil Museum in Nova Scotia found a long, curved fossil jaw, bristling with teeth.