Costa Rica is chockablock with interesting critters, but the ones that impressed me most were leafcutter ants. Once you start looking you see them everywhere, dutifully hauling chunks of greenery to their nests, leaving perforated foliage behind.
I assumed leafcutter ants eat the leaves once they get home, but no, they farm them. Or rather, they use the leaves as fertilizer to grow fungus which feeds the colony, the population of which can be up to 8 million. That’s a lot of fungus.
Here’s video I took of these ants. Just look at these ambitious fellows.