Dozens of times over the eons, rove beetles have made complex, independent adaptations to live inside the nests of ants — the phenomenon of convergent evolution. Biologists want to know if this shows patterns at work in natural selection.
For decades, genetics and biochemistry have formed the bedrock of developmental biology. But it turns out that physical forces — the way cells push, pull and squeeze each other — play a huge role, too.
Despite the triumph of Einstein's general relativity physicists still wonder whether it will someday face the same fate as Newton's law. While Einstein's gravity has passed every test so far, nobody knows for sure that it applies everywhere, under all conditions.
Despite weighing less than half an ounce, mountain chickadees are able to survive harsh winters. How do they do it? By spending the fall hiding as many as 80,000 individual seeds, which they then retrieve — by memory — during the winter.