These scientists made 2,879 tiny clay caterpillars and hid them all over the world

The fake caterpillars revealed that, indeed, predation is highest near the equator and lowest near the poles; for every 1 degree of latitude north or south of the equator, the odds of a caterpillar getting attacked decreased by 2.7 percent. So a caterpillar in Zackenberg, Greenland was about 87 percent less likely to get bitten than a caterpillar at the equator.