Humans are causing evolution on a grand scale – and it is costing us hundreds of billions of dollars each year, says a Harvard biologist.Every time a strain of bacteria becomes resistant to an antibiotic, or a weed mutates so it can thrive after being sprayed with a herbicide, there is a financial cost to humankind, Stephen Palumbi points out. He estimates that cost to be at least $100 billion every year in the US alone.

He thinks humans must implement strategies to slow evolution down as a matter of urgency. Interspersing the use of one herbicide with another is one option. Another ploy is to withhold a powerful treatment as a last resort, to prevent resistance developing.