Lecture 2 - What is Paleobiology?

Fossils provide

the only direct record of the history of life

Body fossils look like

Trace fossils look like

Terrestrial vertebrates look like

Flying vertebrates look like

Swimming vertebrates look like

Hallucigenia looks like

What are birds

Dinosaurs

Macroevolution

examining patterns and hypothesizing mechanisms of evolutionary change over long period of time

fossils are good for macroevolution

Can studies of population genetics alone explain long-term patterns we see in the fossil record?

Highly unlikely

Species longevity

• a long-term evolutionary pattern that is KNOWN in fossil record but NOT predictable from living world alone

• species can exist for long and variable times

Taxonomic turnover

• a long-term evolutionary pattern that is KNOWN in fossil record but NOT predictable from living world alone

• higher taxa turn over at a higher rate over geological time

Explosive diversification

• a long-term evolutionary pattern that is KNOWN in fossil record but NOT predictable from living world alone

• episodes of increased rate of diversification have occurred more than once

Mass extinctions

• a long-term evolutionary pattern that is KNOWN in fossil record but NOT predictable from living world alone

• episodes of increased extinction rates have occurred more than once