For the night excursion, we take flashlights and headlamps. Our guide shines his light to the top of a very tall tree and shows us a slow-moving sloth that's apparently been there all week. Looking down at our feet, we see a long millipede, and a moving 'carpet' of leaf-cutter ants carrying leaves much larger than themselves back to their underground nest. "Careful, don't step on them", he says.

Bats flutter overhead as we sweat in the humid darkness. Stopping at some small holes along the trail, our guide wiggles a little stick in the hole, and a large tarantula leaps out to attack it. We see several 'ground tarantulas' this way -- plus smaller 'pink-footed' tree tarantulas on nearby tree trunks. Switching to an ultraviolet flashlight, we also find small tree scorpions (their exoskeletons glow under UV light).

Wrapping up our walk through the dark forest, it's time for bed. It was an interesting excursion, but somehow even under the mosquito netting that covers the bed, I can't help feeling like maybe things are crawling on me -- but it's probably just my imagination (I'm hoping). Tomorrow, an extra-early 4:30am birdwatching excursion, and then the flight home.