Biological anthropology Humans have: 1. an evolutionary history: phylogeny All heritable changes that have brought humans to present form Biological evolution is not progressive e.g., not always simple to complex 2. an individual life history: ontogeny Phenotypic expression of traits & attributes Based on genetic and environment factors

Two Basic Ways of explaining natural phenomena 1. Supernatural – Immune from evidence – Immune from hypothesis testing – Explanations can’t be proved or disproved Belief systems – Accepted on faith. superstitions, myths, religions, philosophies – Important in social structuring ethics, morals, laws – Affect the way individuals behave toward one another Can hold groups of individuals together OR – can keep groups of individuals apart. – enhance the psychological well-being of individuals. provide hope and purpose to life – Beliefs are transmitted by teaching

Ca. 42,000 religions

2. Scientific explanations Science = a process for acquiring information about the natural world Gotten through our senses – Empirical evidence – Observations and experiments are repeatable – Facts are supported by evidence.

Scientific investigations 1. Something unusual is observed. 2. Leads to a question: does this skull represent a biped? 3. One or more hypotheses are developed. – hypothesis: a testable tentative explanation for a phenomenon. – A null hypothesis: (H 0 ) – An alternative hypothesIs (H 1 ) Approach: collect data (evidence) and attempt to reject (refute, falsify) each hypothesis. Bias is removed by attempting to reject hypotheses. They can’t be proven.

Accumulations of verifiable facts lead to the discovery of fundamental truths = theories Theory: means something different to different groups of people. Science: willing to modify conclusions if new evidence falsifies previous evidence.

Effects of isolation on diversity Cultural anthropology

Cultural vs. biological evolution Culture: non-biological adaptations Sum total of learned traditions, beliefs, values, and inventions used by a particular society. Transmission between generations is non-genetic: teaching Cultural evolution is progressive Predictable, sequential improvements in a particular direction can be made through time.

Reconstructing the recent past Olsen-Chubbuck site Discovered in 1957

Cross-section of an ancient arroyo Long-buried by wind-borne deposits.

Part of the excavated arroyo. Arroyo was 170 feet long Remains of 193 bison Bison occidentalis not Bison bison Bones in three layers: Bottom: complete skeletons of 13 individual bison. Middle: bones of partially butchered individuals Top layer: individual bones and partially articulated bones in similar piles. Dated at 8,500 ybp Holocene epoch

Projectile points associated with the bison bones. Material culture

The reconstruction of events 1. Time of year. 2. Wind direction 3. The stampede.

75% of the bison were completely burchered. Based on numbers of mature bulls, immature bulls, mature cows, immature cows, and calves The butchered bison estimated to have produiced 56,640 pounds of fresh meat 4,000 pounds of edible internal organs 5,400 pounds of fat. 100 people could have completed the butchering in half a day. Enough meat, internal organs, and fat to feed a group of 150 for 23 days.

Example of Prehistoric cultural evolution e.g. projectile points Stone industry – traditions ca. 11,200 years ago – Dent site - 43 miles NE of Denver – Mammoth hunters: Clovis points ca. 7,000 years ago – E Colorado: Scottsbluff points – SE New Mexico: Plainview points – Bison hunters

Plainview point Clovis point