Goofs

When Keda falls during the hunt, he hits two ledges on the way down (and tries to grab a third, smaller ridge) before landing on the ledge below. But a few seconds later, when the camera travels from the tribe above to the unconscious Keda below, no other ledges protrude between the top and the ledge on which he is lying.

There is a double rainbow shown but the colors of the outer one are wrong. The primary (inner) rainbow is blue to red, but the secondary should be red to blue.

The beards are all nicely groomed and one person has no beard and a partially shaved head, also it appears there was a metal blade knife. Implements to do this would not have been available 20,000 years ago.

The big cat in the movie is supposed to be a Machairodus. However, its teeth are far too large for this genus, looking more like the sabres of Smilodon (which was only ever found in the Americas).

The dominance hierarchy among wolves presented in the film is only exhibited in the real world by captive wolves.

According to this film, after you break your leg ( and reset it) you can walk unaided after a few hours and within days climb trees and run .

In the first cave scene, Kedi is kneeling to approach the wolf, and the bottom of his boot clearly shows a rubber lugged sole.

When Keda descends from a tree to check on injured Alpha, his shoes have black colored rubber soles. Later in a cave, when he stood up, his soles were white in color.

Keda falls through the ice with all his possessions, presumably soaking all of them. A few moments later he is shown to have started a fire.

To start a fire with a two piece wood drill, everything, including the drill, tinder and fuel has to be bone dry.

The presence of the slightest moisture on anything, even in ideal conditions, would make it impossible to start a fire like this.

Keda uses two pieces of wood, usually called a drill, to create fire, consisting of a spindle (the spinning part) and a hearth (the static part that sits on the ground).

He is using his hands to spin the spindle, however, it is way too short and thick for a hand drill. To use your hands to make fire the spindle must be thin and long so as your hands rub together it rotates faster and the length enables more rotations as your hands move down its length.

The setup shown is actually for a bow drill where the length of the spindle doesn't matter as the necessary pressure is maintained from above using a third piece of wood and the speed is generated from the bowstring.

13 minutes in, the double rainbow in the waterfall has colors in the same order; actual double rainbows have red butted against red.

The hunting party is supposed to be in Europe, but are shown hunting American buffalo/bison.

Keda falls and lands on a rock ledge hundreds of metres from the ground, sustaining injuries (perhaps even breaking his leg at this point).

He then climbs downwards, perhaps 50 to 100 meters (certainly far enough to survive a fall into the water,) despite being injured, on an overhanging face with tiny foot and hand holds, having no apparent experience, no rope and no protection or climbing shoes.

Even the top rock climbers in the world today would be unable to climb up such a face in these circumstances, let alone downwards as is shown.

After having fallen in the water, Keda is shown completely wet, lying on thin skins, on ice, in the wind, almost naked, next to a tiny fire at least six feet away with his back to it.

As shown, all the heat from the fire would go straight up and Keda would feel none of it, and in these circumstances he would die from exposure within minutes.