LIFESCI 1 Lecture Notes - Lecture 5: Radiocarbon Dating, Molecular Clock, Hard Tissue
Document Summary
Answer: 4 (count number of nodes besides og) Clicker question: character states that are similar because of descent from a common ancestor are: Synamphormorphy is always homology but not vice versa. Look at what traits are most common so they are the next one to have evolved. Tree 1 is the better tree because it is the more parsimonious (more straightforward and simpler), less number of changes. When they diverge, they have changes in gene sequence. We can look at changes in gene sequence and see how long ago they share the common ancestor by looking at molecular clock. Hard tissues form fossils, soft tissues do not. Temporal bias: volcanic activity (big release of ash/particles that bury organisms-leave a better fossil record) Abundance: only a small percentage of individuals within a species forms fossils. Lower chance of rare organisms to leave a fossil record.
