Out: Darwin. In: Lamarck!

The existence of this parallel means of inheritance, in which something a parent experiences alters the DNA he or she passes on to children, suggests that evolution might happen much faster than the Darwinian model implies. “Darwinian evolution is quite slow,” says Whitelaw. But if children can inherit DNA that bears the physical marks of their parents’ experiences, they are likely to be much better adapted to the world they’re born into, all in a single generation. Water fleas pop out helmets immediately if mom lived in a world of predators; by Darwin’s lights, a population of helmeted fleas would take many generations to emerge through random variation and natural selection. The new Lamarckism promises to “reveal how the environment affects the genome to determine the ultimate traits of an individual,” says Whitelaw.