The snake that lunges at Yossi as he climbs the tree is a fanged venomous snake. However, the snake that he throws to the ground is a constrictor.
After Yossi cuts the worm out of his head, for most of the rest of the movie the cut is no longer there.
When Yossi is removing the botfly larvae from his head, Daniel Radcliffe instead pulls out an earthworm.
(at around 14 min) The Cessna 208 Caravan does not carry a registration number, only a Bolivian flag on the tail fin.
Yossi was apparently planning his trip through the wild Bolivian jungle for weeks or months. He knew how dangerous and unpredictable things might get, yet he neglected to take along even the most basic supplies, including a first aid kit, bug repellent, foot powder, water purification tablets, a mosquito net, food, extra socks, a knife, etc. Even a Boy Scout would have had the foresight to include these items in his backpack. The fact that he had none of these very nearly cost him his life.
Yossi spends about two weeks alone in the hot, humid jungle trying to survive and reach safety. Yet despite the fact that his journey gets more and more arduous, and that he is utterly exhausted at the end of each day, not once is he shown to be sweating.
Marcus's feet are shown as being cut and blistered to the point where they are bleeding, preventing him from walking more than a few steps.
Building the raft, launching it and travelling down the rapids probably took less than a day, yet when the group are back on dry land again Marcus's feet have miraculously healed and show no damage at all.
Building the raft, launching it and travelling down the rapids probably took less than a day, yet when the group are back on dry land again Marcus's feet have miraculously healed and show no damage at all.
When Kevin approaches the boat operator to help find Yossi, the clear outline of a modern day cellphone is visible in Kevin's right pocket. This period was well before smartphones.
Opening scenes feature a blue 1991 Dodge Ram D/W-Series Cabina Simple, produced ten years after the events.
The aircraft used for the flight scenes is a Cessna 208 Caravan. The first flight of this aircraft type was not until December 1982, a year after the events.
(at around 8 min 30 s) When Marcus, Yossi and Kevin are walking up the street, just before entering Comunidad Israelita Macabi De La Paz, they pass a 1984 Renault 18 Break Série 2 parked to the left side of view. A car produced three years after the events took place.
The plane used to fly to the jungle at around 15 minutes is a Cessna Caravan. This aircraft was first certified by the FAA in late 1984.
At 1:04 and for a fraction of second only, just after the blue truck disappears at the bottom of the screen, one can see a drone hovering above the trail road.
At 1:01, after he leaves a pack of supplies for his friend and walks down a stone embankment, you can see a crew member move through a gap in the stone.
When the raft is washed off the rock and back into the river, some kind of wooden frame is visible on the far bank.
About 15 minutes in, as they first embark into the Bolivian jungle, they see a pair of Oriental Pied Hornbill (Anthracoceros albirostris) birds which are native to Asia.
When Yossi makes it to the river bank, after being tossed into the rapids, the river behind him is flowing to the left of the screen. After spending days lost in the jungle, he finally makes his way back to the river, but it's flowing to the right of the screen. Having never crossed it between those two sequences, that is impossible.
After Kevin swims to safety and the raft is destroyed, Yossi is washed down the river. At one point, a slow motion sequence shows him suffering a head injury underwater as a reddish burst of blood spills in the water. In subsequent scenes, however, whatever the shooting angle, his scalp appears to be intact, without any visible wound or bleeding.
When Yossi take a bath in the river he looks like he was straight from the gym, but after a few weeks he lost a lot of pounds, his arms are skinny to the bone. Also, his beard never grow, no matter what...