We’ve discussed before how endangered species are at risk from the increased likelihood of inbreeding, which leads to unhealthy offspring. There’s another danger to letting the numbers of animals in a given species become too low. It’s called genetic drift. Learn more on this Moment of Science.
Genghis Khan is one of the greatest conquerors who ever lived. Learn about his long lasting "genetic empire" that's still going strong today.
Their descendants were even more vain, so in 16th century Venice mirror makers discovered the technique of backing a piece of glass with a reflecting metal composed of tin and mercury, producing a much clearer reflection.