1. Humans are born physically, socially, and cognitively immature compared to other species.
a. Describe why a lengthened juvenile period in our species is helpful for gains in all three areas.
b. Why do you think this immaturity has evolved?
Humans are unique in that they are born physically, socially and cognitively immature compared to other species, which in turn is an advantage for them. When describing the evolution of humans, a term that is commonly heard is neoteny. Neoteny simply means “holding youth” (pg. 88), which is describing the slow development from childhood into adulthood. Compared to chimpanzees, human’s physical features develop slower and humans tend to keep their youthful characteristics well into adulthood. Bjorklund and Pellegrini (2002) claim an advantage of being physically immature is that adults find these younger characteristics appealing and find babies to be adorable, even though they cry and keep adults up all night. In other words “it is hard not to love them” (Bjorklund & Pellegrini, 2002, p. 89). Therefore it has been suggested that these young features are what provoke caretaking behaviors (Lorenz, 1965 as cited in Bjorklund & Pellegrini, 2002).
Cognitively speaking, humans’ brains develop while they are in the womb, but continue to develop after they are born. This extended time to allow the brain to grow and to create more neurons produces a larger brain (Finlay & Darlington, 1995 as cited in Bjorklund & Pellegrini, 2002). Due to the slow maturation of the brain, the brain is able to allow synapses and dendrites to grow for a longer period of time, which in turn develops more connections (Gibson, 1991 as cited in Bjorklund & Pellegrini, 2002). A larger brain means more plasticity when it comes to learning and memory and a longer life.
A larger brain also helps humans socially. Due to the fact that the brain developed more connections, it was able to help them work together with other members of the group, yet be able to compete with them as well. This ability was ultimately seen as the cause of human’s intelligence (Alexander, 1989; Bjorklund & Harnishfeger, 1995; Byrne & Whiten, 1988; Geary & Flinn, 2001; Humphrey, 1976 as cited in Bjorklund & Pellegrini, 2002). Additionally, this longer period of youthfulness allows humans to put into practice adult roles (Bjorklund & Pellegrini, 2002).
I believe this immaturity has evolved to essentially help us to become a better species overall. If we did not have an extended juvenile period, it seems as though humans would not be prepared to be adults. It is important to have the periods of childhood and adolescence because it helps with the transition into adulthood. Additionally, if our brain did not have more time to grow, we would not have the large brain we have today. Therefore I would assume the average human would not live as long as we do today. Also, if our brain did not develop the many neuron connections it has today, we may not have the ability...