BBC Science Focus
WHERE’S THE EVIDENCE THAT EVOLUTION IS HAPPENING TODAY?
There’s plenty of evidence. A good example came to light in 2016, when biologists in Japan announced they had discovered a new species of bacteria, Ideonella sakaiensis, that had evolved to eat PET plastic. This plastic has only been manufactured since the 1940s, so the bacteria have evolved to eat it in under a century.
Larger organisms can evolve rapidly, too. In the early 1990s, one species of cricket (Teleogryllus oceanicus) living on the Hawaiian island of Kauai became the target of lethal parasitic flies. The parasites located their victims by listening out for the crickets’ chirps. By 2003, the crickets had evolved: a new genetic mutation that left males physically unable to use their wings to chirp had swept across the island. What had been a population of chirping crickets became a population of mostly silent ones.