User:Cornyon/Walking/Eric Heldt Peer Review

General info

 * Whose work are you reviewing?

Cornyon


 * Link to draft you're reviewing
 * https://en.wikipedia.org/wiki/User:Cornyon/Walking?veaction=edit&preload=Template%3ADashboard.wikiedu.org_draft_template


 * Link to the current version of the article (if it exists)
 * Walking

Evaluate the drafted changes
The content added is relevant to the topic. The content added is very detailed and someone who is interested in the topic of walking and its origins and biomechanics would most likely be happy with the information they are left with. I really liked how the stuff you added to the biomechanics part ties into the energy saving narrative of the origins part. Overall I think the content added is pretty good and adds good details about walking for humans,

I think my one main change would to keep first part of origins from the main article that's about the non human origins and just replace the bottom part with your new information. looking somewhat like this.

It is theorized that "walking" among tetrapods originated underwater with air-breathing fish that could "walk" underwater, giving rise (potentially with vertebrates like Tiktaalik) to the plethora of land-dwelling life that walk on four or two limbs. While terrestrial tetrapods are theorised to have a single origin, arthropods and their relatives are thought to have independently evolved walking several times, specifically in insects, myriapods, chelicerates, tardigrades, onychophorans, and crustaceans. Little skates, members of the demersal fish community, can propel themselves by pushing off the ocean floor with their pelvic fins, using neural mechanisms which evolved as early as 420 million years ago, before vertebrates set foot on land.

Data in the fossil record indicate that among hominid ancestors, bipedal walking was one of the first defining characteristics to emerge, predating other defining characteristics of Hominidae. [Judging from footprints discovered on a former shore in Kenya, it is thought possible that ancestors of modern humans were walking in ways very similar to the present activity as many as 3 million years ago.]

Today, the walking gait of humans is unique and differs significantly from bipedal or quadrupedal walking gaits of other primates, like chimpanzees, and it is believed to have been selectively advantageous in hominid ancestors in the Miocene due to metabolic energy efficiency. Human walking has been found to be slightly more energy efficient than travel of a quadrupedal mammal of similar size. Further, comparing chimpanzee quadrupedal travel to that of true quadrupedal animals has indicated that chimpanzees used one-hundred and fifty percent of energy compared to true quadrupeds. In 2007, anthropologists Michael D. Sockol, David A. Raichlen, and Herman Pontzer conducted an experiment further exploring the origin of human bipedalism, using chimpanzee and human energetic costs of locomotion. They found that the mass-specific energy costs expected for human walking travel is less than what would be expected for an animal of similar size and approximately seventy-five percent less costly than that of chimpanzees. Chimpanzee quadrupedal and bipedal energy costs are found to be relatively equal, with chimpanzee bipedalism costing roughly ten percent more than quadrupedal. The energy efficiency of human locomotion can be accounted for by the reduced use of muscle in walking, due to an upright posture which places ground reaction forces at the hip and knee. Interestingly, the same study found that among chimpanzee individuals, the energy costs for bipedal and quadrupedal walking varied significantly, and those that flexed their knees and hips to a greater degree and took a more upright posture were able to save more energy than chimpanzees that did not. Further, compared to other apes, humans have longer legs and dorsally oriented ischia, which result in longer hamstring extensor moments. Further, humans have long femoral necks, meaning that while walking, hip muscles do not require as much energy to flex while moving. These slight kinematic and anatomic differences demonstrate how bipedal walking may have developed as the dominant means of locomotion among early hominins based off of energy savings.