Adaptations of Evolutionary Environments Article : Infant and Child Death in the Environment of Evolutionary Adaptation Haley McCormick Joey Hoy Kira Rohrer

Environment of Evolutionary Adaptedness (EEA)  This term refers to the environment in which an species is adapted to live in. Referring to the way this species is adapted to find food, reproduce, etc.  The EEA is comprised of a combination of different environments that were present during or directly proceeding the Paleolithic period of time.

Infant Mortality Rate and Child Mortality Rate  Infant Mortality Rate (IMR) is the rate at which an infant will not survive to the age of 1  Child Mortality Rate is the rate at which a child will not survive to the reproductive age of 15  Infant and Child Mortality Rate may be one of the strongest forces of evolutionary selection  Before modern civilizations, not many children and infants survived in the environment they were raised

Hunter-gatherer Data  Article used modern hunter-gatherer societies to study IMR and CMR due to their demographic being similar to ancestral societies  Archaeological data was also used as a check against modern hunter-gatherer societies. The sample only included societies that were not influenced by modern resources. These influence affect mortality rates.  IMR and CMR are high in hunter-gatherer societies showing an almost even odd to surviving versus dying  Those that did not survive did not pass on their genes

Historical Data  Within the past 10,000 years of the present human EEA, there is a possibility of complex new adaptations or alteration of previous adaptations  Historical data can show a continuation of the new adaptations that alter infant and child survival  Data can be lost due to smaller remains decaying quicker, low record of child deaths, and no life stories recorded  Reason for decline in IMR and CMR may be due to education, food supply, new medicines, and modern technology

Agriculturist Data  Lowest IMR and CMR of all groups analyzed  Results of positive exposure to modernization  Likely had lower mortality due to modernized medicine and technology

Non-Human Primate Data  Phylogenetic relationship with IMR and CMR as species more closely related to humans have more similar mortality rates  The pattern of human infant mortality appears to be similar to that of Neanderthals, chimps, and gorillas, but not to orangutans or bonobos (lower) and other primates (higher)

Causes of Infant and Child Mortality  Interesting that humans have a higher CMR than any other ape species  Lengthier childhoods (importance)  Resources, Socio-economic status, food access  Maternal care is strongest predictor of mortality  Family size and hygienic practices  Competing Theory increased fertility

Critical Review  Agreement  Using isolated tribes with no modern influence  Interesting humans have higher CMR than great apes  Lengthier childhoods=more opportunities to die  We are still evolving  Disagreement  Reliability of data  Didn’t matter if potential to be genetically fit if they didn’t overcome dangers of childhood  What mediating factors are there that impact the IMR and CMR and how do they impact the EEA?