We’ve talked a lot of about how and what we know about the past. You should be able to answer to apply your knowledge on the following topics:
How organisms preserved as fossils
Why some organisms preserve better than others
Some special circumstances under which soft tissues may be preserved
How we know how old rocks and fossils are – relative to each other, and in years
What kinds of fossil organisms are especially useful for relative dating
Why in some cases we can date rocks and fossils more precisely than others
Where sediments tend to accumulate
Why the fossil record of some environments is better than others
How paleontologists use the present to study the past
Why sometimes it is difficult to reconstruct the past because modern examples are unknown
How one might use confluence of evidence to build support for a particular hypothesis
What peer review is, and what it has to do with science
If
you understanding these kinds of concepts,….
-- you would be able to understand why it would be unusual and interesting to find fossils of soft-bodied animals or fossils from dry upland habitats [because fossils of these types are rare, since soft-parts usually rot away and most fossils form in aquatic sedimentary habitats]
-- you would be able to understand why it is difficult to figure out what an organism looked like from the late Precambrian or to understand the ocean dynamics of a huge continental sea [because in both cases we don’t have any modern examples to study]
-- you would be able to understand why many forms of independent evidence are used to confirm a speculate hypothesis about, say, an extraterrestrial impact causing an extinction, or a fossil group being much more ancient than previously recognized [confluence of evidence; we can’t experiment on the past, so we must test all available information that relate to the truth of the hypothesis]
Outline
of overarching concepts:
The following outline will give you the essentials of the course as
I see it. This outline does not contain all the information, but it suggests
what is most important. In order to create a well-rounded exam, I will try to
make sure that there are questions relating to all of these points.
The outline is divided into three parts:
1) The actual interpretation of the history of life
2) The kind of evidence that is used to further our understanding of the history of life
3) The means by wish scientists do research and publish on it
1) Substantive (the actual
interpretation of the history of life)
What are the primary patterns in the history of life?
- includes major events
- includes important organisms
- general patterns that are repeated, and long-term trends
What are the primary processes that cause the patterns in
the history of life?
- plate tectonics
- evolution
- extinction
- climate and sea level fluctuation
- sedimentation and erosion
2) Methodological (the way in
which we study the history of nature)
How do
paleontologists knopw about the past? Always ask: “How do we know?”
- fossilization (information about the organism and its environment)
- sediments (information about the environment)
- radioisotopes (age)
What kinds
of things do we know little about due to lack of preservation?
- behavior
- soft parts
- color
What are
some basic conceptual assumptions when we study paleontology?
- physical laws operated in the past as they do today (physical uniformitarianism)
- sediments are deposited more or less horizontally, with the youngest on top
- we can interpret the nature of past organisms based on similar organisms today (biological uniformitarianism)
3) Doing research (the actual practice of study and
communication)
How do
scientists choose to do work and write a research paper?
- scientists want to contribute to understandings of important patterns and processes
- the corrolary is that not all fossils are equally interesting; good paleontologists do not study just any fossils, for no particular reason
- some interesting questions cannot be answered due to lack of data, so scientists much choose research projects that balance scientific significance with practical realities of the fossil record, time, funding, human resources, etc.
- to keep scientists publishing the highest quality scientific research, manuscripts are peer-reviewed; the vast majority are either rejected or accepted only if revisions are made (this is also how funding works)
How does scientific
work get into the public news media?
- although there are thousands of journals (=technical magazines), two journals provide the basis for most media news reports: Science and Nature
- when scientific literature is reported in the media, the content is simplified and put into context so lay audiences can understand why the research is important
- only topics of special significance and public interest are reported by the news media to the general public; dinosaurs and fossil hominids are relatively frequently reported upon due to the public’s fascination with these taxa, but the vast majority of paleontological research is never reported to the news media