John Bates stands by accusations that 2015 study was rushed and biased, but says he only guessed that motivations were political.
Study estimates that without new "congestion pricing" policy, kids would have suffered 45 percent more asthma attacks.
Elephants bring tourists and tourists bring money.
A new study suggests the ecosystem -- and others like it -- can't be relied upon to remove excess carbon from the atmosphere.
Two gangs flow ivory from the wild to Mombasa, and then to the market.