Dodos, Dinos, and Deinococcus History of A Habitable Planet Discussion CHAPTER 17: Questions 1) What kinds of landscape features are characteristic of gla

Dodos, Dinos, and Deinococcus History of A Habitable Planet Discussion CHAPTER 17: Questions

1) What kinds of landscape features are characteristic of glacial erosion?

2) What kinds of landscape features are characteristic of glacial deposition?

3) Consider a lecture hall filled with 100 students, 50 men and 50 women.
When we say that the ratio of men to women (men/women) is 1:1 we mean that there are the same number of men as there are women.

Now, if 25 women leave the room, then there are only 75 people left and the ratio of men to women would be 50/25, or 2:1. Now there are twice as many men as there are women in the room.
OK, get ready to think!
Consider an OCEAN that is filled with two different kinds of water molecules—
H216O and H218O
(This is because there are two kinds of oxygen, heavy and light, known as 16O and 18O)

Answer the following questions:

A) Which is heavier, H216O or H218O?
B) Which is more likely to leave the ocean during evaporation. H216O or H218O?
C) If the evaporated molecule gets trapped in glacial ice during cold time periods, i.e. not allowed to return to the sea, THEN which kind of water molecule becomes enriched in the remaining ocean water? H216O or H218O?

4) A particular level in a deep-sea core has an unusually high ratio of 18O relative to 16O—does this portion of the core represent a global warm-period or a global cool-period?

5) Look at Fig 17.6 (titled “Climate Changes During the Cenozoic”) and compare it to Figure 18.5 (“Cenozoic Vegetation/Climate”) in the next chapter. Both plots of temperature (one based on O-isotopes and one based on types of fossil plants) mark a significant cooling even in the Cenozoic. When does this cooling occur? Be as specific as possible.

6) Not all climate change occurs on the scale of Milankovitch Cycles. Shorter term changes (10’s to 100’s of years) can involve big temperature fluctuations (1-5 degrees).

What do you think could cause short-term climate change on the order of decades or centuries?

CHAPTER 18: Questions

A couple of nice web sites to accompany your textbook chapter—
http://www.ucmp.berkeley.edu/mammal/mammal.html (Links to an external site.)Links to an external site.

(In particular, the site above is worth poking around. It will help prepare you for the exam.)

http://www.ultimateungulate.com/ (Links to an external site.)Links to an external site.

1) Mammals first appear in the Mesozoic Era, which is the so-called “age of dinosaurs.”
If they first appear in the Mesozoic, then why is the Cenozoic so often referred to as the “Age of Mammals”??

2) Of the four mammal groups–Marsupials/Multituberculates/Monotremes/Eutheria—

A) Which group do humans belong to?
B) Which group no longer exists (i.e. is extinct)

3) Consider an ecological setting where we have certain predators and prey.

If the prey become faster—literally faster runners—then what would you expect of the predators? Would they, over time, become faster or slower?

4) Look at Table 18.1 which details some trends in mammalian evolution during the Cenozoic. Associated with the lengthening of limbs, there is a trend towards “digitigrade” locomotion.

What is digitigrade locomotion and is it related to your answer to the previous question?

5) Ungulates come in two general types (artio- and perrisodactyls). What are ungulates?

Did the ratio of these two types remain constant through the Cenozoic?

6) Compared to reptiles, WHY do mammals need to eat more frequently?

CHAPTER 19: Questions

1) They sound so similar—hominid and hominoid—but they’re different!

What is a hominid?
What is a hominoid?

2) How far back in the fossil record do we find the very broad group of animals known as “Primates”?

How far back do we find the more specific group called hominids?

3) Go on-line and do a search in order to learn about the famous Piltdown Hoax—a rather cruel trick in which a chimpanzee jaw was crudely attached to a relatively modern human skull, and then touted as an actual early human fossil!

Some historians of science have pointed out that “Piltdown Man” remained in the scientific literature for an unusually long period of time, even though evidence demonstrating the absurdity of the “fossil” was quickly established.

Here’s the QUESTION–
Why were scientists resistant to giving up on Piltdown? Why did it take them so long to say “yeah, this stupid thing is not real, it is nothing more than a hoax!” ?

(Hint: They had thought that the Piltdown fossil supported an important feature of human evolultion….which turned out to be wrong!)

4) Homo sapiens refers to both genus and species. Genus=Homo, species=sapiens.

Lots of different critters within the genus Homo.

For example: Homo habilis, Homo ergaster, Homo heidelbergensis, Homo neanderthalensis, etc.!

Today, there is only us (H. sapiens), but how far back in the geologic record does one have to go in order to find multiple co-existing species within the genus Homo? Explain.

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The textbook is Historical Geology, Evolution of Earth and Life Through Time, 7th Edition, by Wicander and Monroe.