Readings:
E-reserves: “Dinosaur endothermy: Some like it hot”, from Fastovsky & Weishampel.
Go to http://ereserves.library.arizona.edu/ers_search/OSCRsrchform.php3
Select Geos 308 from pull-down menu. The password is: fossil
1. The record of diversity through time
Possible biases/error in estimating trends in diversity
Early evolution on the earth
Starting environmental conditions and why the record is incomplete
Types of life: autotroph vs. heterotroph; aerobic vs anerobic; procaryotic vs
eucaryotic.
Role of life in affecting the global environment; stromatolites, oxygen and bif.
Timing of major innovations: the first fossils, eucaryotic cells, metazoans and the
Ediacara fauna, small shellies, trace fossils, hard parts.
The Cambrian “big bang” or “explosion”
Dating the base of the Cambrian
External vs internal triggers for the diversification
The possible functions of hard parts
Lessons of the Burgess Shale: diversity, disparity, extinction.
Three evolutionary faunas – what are they, what’s in ‘em
Terrestrialization
The three invasions of the land: plants, arthropods, vertebrates.
Major vertebrate groups
Unjawed (agnathan) vertebrates, jawed vertebrates, tetrapod vertebrates,
amniote vertebrates.
Why is the traditional group “reptiles” such a problem in a cladistic
system?
The major groups of dinosaurs and their evolutionary relations: theropods,
sauropods, ankylosaurs, stegosaurs, pachycephalosaurs, ceratopsians, ornithopods.
2. How to reconstruct fossils as once-living, functioning, interacting organisms when you only have fossil remains to work with.
Approaches:
a) Analogy with living representatives (teeth, correlation of posture with metabolism; comparison of sauropod morphology with morphology of terrestrial and semi-aquatic vertebrates).
b) b) Model-making (both physical models -- for example, vocalization in hadrosaurs, bite strength in T. rex —and mathematical models, for example how wingspan in Quetzalcoatalus was estimated.
c) Direct analysis of remains:, Condition of dinosaur bones and teeth in nest sites,
bite strength in T. rex, Evidence from the rocks and paleogeography (analyzing
trackways for dino speed, herding, posture - with implications for dino metabolism, behavior geographic distribution of dino fossils, dinosaur nest sites.)
What are the strengths and weakness of each approach? How can approaches be combined? Examples?
3. Endothermy vs ecothermy in dinosaurs. What’s the difference and why does it matter?
Pro and con evidence for endothermy in dinosaurs; approaches employed, evidence used. Relative strengths and weaknesses of evidence. What do you find most convincing and why?
Some general tips:
Notes are also now posted for Richard Thompson’s lecture and for the
video.
Class handouts are likely to have important information on them.
The notes posted on the web are not a substitute for actually being at the lecture and taking your own supplementary notes.
I did not get to “Sue’s Tale” in lecture: read the Web notes (at the end of the notes on dinosaurs) on this issue. I will ask a question about it.
If I can figure out a way to have you do some calculations or work from graphs, I will do so. I can be like that.
When major events in the history of life occurred is important.
You should be developing critical skills so that you can distinguish a strong hypothesis from a weak one. Although I like dinosaurs, I’m mostly using them to illustrate the lines of evidence and reasoning that goes into making interpretations about fossils. Some dino interpretations are unsupported speculation, others are based on good evidence and are well-reasoned. Can you tell the difference?
And don’t forget the geologic time scale....