BIOL 2081C Lecture Notes - Lecture 36: Homo Heidelbergensis, Y Chromosome, Zygosity
Document Summary
Learning objectives: differentiate between a derived and an ancestral trait, indicating which of the traits described are derived compared to chimpanzees. Derived traits are traits that are present in an organism, but were absent in the last common ancestor of the group being considered. Ancestral traits are traits shared by a group of organisms as a result of descent from a common ancestor in history. Comparison of chimps & derived traits refer to lecture 36 notes: during recent human evolution, there are three major examples of genes under positive selection. The forces causing these selection events include climate (pigmentation genes), disease (hemoglobin genes), and dietary changes (lactase and amylase). Describe the following terms using the above forces and genes/traits as examples where appropriate: Derived traits: since the advent of agriculture about 10,000 years ago and the resultant increase in population density, infectious diseases have been a health burden on human populations.
