![]() ![]() The resulting selection for improved throwing and clubbing prowess, prolonged over millions of years, led to numerous anatomical changes throughout the body, including those that characterize the evolution of the human hand. It is suggested that the tools were hand-held weapons that were hurled or swung as bludgeons at adversaries during disputes, providing the aggressors with advantages that in various ways promoted reproductive success. However, basic questions remain: what kind of tools? In what manner and for what purpose were they used? How did such behaviour provide reproductive advantages sufficient to drive natural selection during the millions of years required to transform the ancestral ape hand into the human hand?Ĭhimpanzee hand, a model for the hand of the hominid ancestor (left), and the human hand.Ī proposal that offers an answer to these questions is provided in the following report. This approach is consistent with evidence that an early hominid (hominin) behaviour was bipedal gait, which would have ‘freed the hands’ for greater use of tools. Although no comprehensive account has been offered, there is general agreement that the anatomical reconstruction of the hand during human evolution was somehow linked with tool behaviour. This striking exception to the primate pattern clearly requires an evolutionary explanation ( Marzke & Marzke, 2000 Fig. In contrast, the human hand has a much larger, more muscular, mobile, and fully opposable thumb combined with fingers that have shortened and straightened. Modern Language Association, 8th ed., 2016.įor more info, see the MLA citation guide.The typical primate hand is characterized by a diminutive thumb in combination with long, curved fingers ( Midlo, 1934). February 4, 2019, /experiments/hand-made. Last modified January 23, 2020.įor more info, see the Chicago Manual citation guide. "Hand Made." ASU - Ask An Anthropologist. Retrieved May 27, 2023, from Īmerican Psychological Association, 6th ed., 2nd printing, 2009.įor more info, see the APA citation guide. ![]() Publisher: Arizona State University Institute of Human Origins Ask An AnthropologistĪPA Style Amy Peterson.They spend a lot time in trees, so they also have opposable toes (like thumbs) on their feet that let them easily climb and hold onto branches. So, chimps have thicker finger bones and stiffer wrists to support their weight. Chimps use their hands when they walk on the ground, which is called knuckle walking. Our closest living relatives, chimpanzees, have hands and feet that are similar to ours, but with some key differences. They’re much faster than we are, but they can’t do delicate work like we can. For example, dog paws and horse hooves are adapted for running quickly. They might have paws, hooves, or fins, which are better suited to the places they live and the things they do to survive. Many other animals don’t have hands like we do. The flexibility of our hands allows us to accomplish tasks that other animals can’t, like building this structure. Now, take off your mitts and try to build the structure again.įrom this experiment, we learned that our hands are very flexible-when not wearing mitts. Take the blocks and attempt to build the Lego structure in the pictures below.ģ. Put on the oven mitts or mittens, making sure that you cannot touch your thumb to your individual fingers.Ģ. ![]() Toy building bricks in large and regular sizes (Lego® and Duplo® or similar)ġ.The need for us to use tools is the reason our hands are so flexible. ![]() Tools provided our ancestors with a great advantage, and so human hands-and brains-continued to evolve to allow tool use. This left their arms and hands free to carry things and make tools. Before human hands evolved to their modern form, our hominin ancestors began walking upright. The human body has evolved through time in response to our environment. When you put on the mitts and try to build a structure, you will get a sense of how hard it would be to do things that we do every day if our hands were shaped differently. We can get food, make tools, and play with toys. Our fingers let us do many things easily and precisely. This experiment will test the dexterity and flexibility of our hands. ![]()
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