who was the first researcher to suggest that facial expressions are pre-verbal
Facial expression The universality hypothesis is the assumption that certain facial expressions and face-related acts/ events are signals of specific emotions (happiness with laughter and smiling, sadness with tears, anger with a clenched jaw, fear with a grimace, surprise with raised eyebrows and wide eyes along with a slight retraction of the ears, and disgust with a wrinkled nose and squinted eyes— emotions which frequently lack the social component of those like shame, pride, jealousy, envy, deferance, etc.) and are recognized by people regardless of culture, language, or time. The belief in the evolutionary basis of these kinds of facial expressions can be traced back to Darwin’s The Expression of the Emotions in Man and Animals. Reviews of the universality hypothesis have been both supportive[18][19] and critical.[20][21] Work in 2013 by Nelson and Russell[22] and Jack et al.[23] has been especially critical.
Prehistory Human prehistory is the period between the use of the first stone tools c. 3.3 million years ago and the invention of writing systems. The earliest writing systems appeared c. 5,300 years ago, but writing was not used in some human cultures until the 19th century or even later. The end of prehistory therefore came at very different dates in different places, and the term is less often used in discussing societies where prehistory ended relatively recently.