In natural philosophy, he asserted Charles Darwin’s theory of evolution unswervingly and set about to test Darwin’s hypothesis that humans arose in Africa. Was also a devout Christian.
In their seminal paper in 1967 in Science, they estimated the divergence time of humans and apes as four to five million years ago, at a time when standard interpretations of the fossil record gave this divergence as at least 10 to as much as 30 million years.
some level of gene flow between geographically separated populations prevented speciation, after the dispersal
all living humans derive from the species Homo erectus that left Africa nearly two million-years-ago
natural selection in regional populations, ever since their original dispersal, is responsible for the regional variants (sometimes called races) we see today
the emergence of Homo sapiens was not restricted to any one area, but was a phenomenon that occurred throughout the entire geographic range where humans lived
homo sapiens arose in Africa and migrated to other parts of the world to replace other hominid species, including homo erectus.
after Homo erectus migrated out of Africa the different populations became reproductively isolated, evolving independently, and in some cases like the Neanderthals, into separate species
Homo sapiens arose in one place, probably Africa (geographically this includes the Middle East)
Homo sapiens ultimately migrated out of Africa and replaced all other human populations, without interbreeding
modern human variation is a relatively recent phenomenon
• Scientific (at least systematic)
4. • Physical/biological
o Some are just interested in human anatomy. Just interested in physiology and osteology. Based upon what kinds of genes we have.
2. Happen through time-perhaps mostly on the past
3. Analogy, inference: to reach a logical conclusion based upon the observation of facts and the application of reason.
4. History, Geology, Archaeology
a. Collection of Data- Induction and Deducation
b. Developing Hypotheses
c. Providing explanations (Proximate and Ultimate)
2. Science is Self Correcting and also Probabilistic
a. Conclusions in knowledge are contingent upon states of knowledge
b. many processes in science are probabilistic
c. There are exceptions to generalizations
3. Science is Parsimonious
a. The principle of parsimony/Occam’s Razor: is a principle of parsimony, economy, or succinctness used in problem-solving. It states that among competing hypotheses, the hypothesis with the fewest assumptions should be selected.
b. This is a rule of thumb only
a. An investigator needs one in order to know what to expect upon beginning a project.
b. It is the source of questions that a researcher will investigate
c. It makes it possible to predict the possible results of a project
Data Generation in the Lab
Testing Hypotheses with statistics