The development of the human form
Since it is based on evolutionary stories at the heart of scientific findings, the film's interpretation of the human body is plausible. This describes how species adapted to environmental selection pressures to survive. However, because of the narrator's contradictory accounts, the film's interpretation is somewhat self-defeating.
Contradictory accounts of limb origin and evolution
The narrator speculates, for example, that primitive limbs originated in the earliest species as a result of their struggle to survive and that mammals akin to humans evolved approximately 125 million years ago (Youtube/Gaffney web). The narrator then states that the human shape never changed once established, which could be understood to imply that the struggle for survival has ended in humans.
Inconclusive explanation and comparison to other mammals
Further, the film's explanation about the human shape is dissatisfying because generally it likens their form to other mammals while also claiming human shape is unique. It is beyond doubt that such an explanation is inconclusive and perhaps loses its meaning because viewers of the film would expect to know how adaptation to selective pressures could have led to the unique human shape.
Veering off-topic and lack of explanation
It can be said that the intended message to teach viewers about the humans shape is lost and the narrator is unconvincing. Rather, the explanation in the film veers off as the narrator focuses on different organisms and their adaptation to selective pressures in different environments. The narrator only fleetingly claims the human shape may have evolved due to increased need to free the front limbs to feed their offspring. For this reason, the film's explanation about the human shape because of selective pressures in their environment is missing. Altogether, the explanation in the film about the shape of humans due to adaptation to selective pressures is unconvincing.
Work cited
Gaffney, Sam. Evolution: The Evolution of humans documentary 2014.
