The jungle is a place where Mother Nature can, if allowed, kill you in a short period of time.

I learned the following: To have two sets of clothes, one dry, one wet. Wear the wet, sleep in the dry. You can't have too many socks. Never sleep on the ground, the ants will carry you off. Mosquito netting is mandatory. Have a backup to your backup packed in a plastic bag, with dessicant, tightly sealed, in another plastic bag - that way there is a 25% chance that backup will work and not be wet. Black palm trees - they have spikes on them- grow right where you need to grab to pull yourself up, over, or through - wear gloves with leather palms. Daily maintenance of boots, feet, knives, radios, weapons is a must. Guesstimate the distance you are going, guesstimate the time it will take you, add 25% minimum, then add a day to guess how long it will take you - as in 10 miles will take 1 day, 8 hours, maybe if you are lucky. Stop at least an hour before sunset to make camp, sooner if you are tired. And finally - freaking howler monkeys will scare the snot out of you, and literally throw poo at you too.