Scientists have been tinkering with the genes of plants and animals for years to cure diseases, make fruits and vegetables heartier or tastier, produce crops that are resistant to pests, drought, and other scourges, or prompt fish to grow faster.
In recent years, however, thanks in part to the ravages of climate change, some researchers who manipulate genes have assumed a new focus: saving the planet. Among other things, they are making grass more palatable for cows and designing climate-friendly cattle that expel less heat-trapping methane. And now they have turned to pigs.
Globally, people consume more pork than any other meat. But there is a big environmental downside to raising pigs. Pigs can’t make three important enzymes they need to digest the nitrogen and phosphorus in their feed. So they poop most of it out, which ends up polluting the air and water. Pig farmers could add these enzymes to pig grain, but that would cost more money, so scientists have come up with another way to fix the problem.