Even more effective than the Magna Carta.
In an effort to try to boost monarch numbers, many American gardeners began planting milkweed in their gardens to give the butterflies a place to eat and bang. But despite this altruistic planting of butterfly no-tell motels, monarch populations kept declining, sometimes at an even more rapid rate. What gives, weeds?
Well, these well-intentioned gardeners would have helped ... if they hadn't planted the wrong goddamn weed. Not all milkweed is created equal, and many gardeners planted tropical milkweed, a species which kills butterfly ambition. So rather than continue the migration (which is necessary to their life cycle), the monarchs would just settle down in their little milkweed patches and never leave, sort of like that star quarterback who ended up back in his parents' basement after dropping out of college.
"If it hadn't been for my bad knee and those 12 DUI arrests, I could've gone pro."
The most ridiculous part is that there are 20 different varieties of milkweed that are A-OK for monarchs, but humans still managed to find the one that's terrible for them, which could mean no more cool science projects. Think of the children!