Jeff Ayers

11/29/14

EASC 300

Prof Garcia

Earth Science Fossil SOL

For students entering middle or high school, it is common for them to take Earth

Science as a subject. The SOL’s for Earth science include many topics, including

everything from the Earth’s position in the solar system to what the Earth is made of.

For Virginia Standards of Learning, the ninth grade SOL states:

ES.9 The student will investigate and understand that many aspects of the history and

evolution of Earth and life can be inferred by studying rocks and fossils. Key concepts

include

a) traces and remains of ancient, often extinct, life are preserved by various

means in many sedimentary rocks;

b) superposition, cross-cutting relationships, index fossils, and radioactive

decay are methods of dating bodies of rock;

c) absolute and relative dating have different applications but can be used

together to determine the age of rocks and structures; and

d) rocks and fossils from many different geologic periods and epochs are

found in Virginia.

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I chose this SOL because it follows a topic of my interest. Fossils have always

been fascinating to me, and to be able to teach students about it would mean that I had

a deeper understanding of it as well. To better be able to teach these strategies, I came

up with two hands-on activities, as well as ten summaries of the topic from different

articles. To test these activities, I used my two roommates. Where one activity is based

on half-life and relative dating, the other is focused on the law of superposition. Before I

discuss the progress of my activities, I will summarize a few articles explaining more

about the SOL.

1."Mr. Eaton's Earth Science." Web log post. Mr. Eaton's Earth Science. N.p., Apr.-

May 2007. Web. 29 Nov. 2014.

This article summarizes that fossils are the mineralized or preserved remains or

traces of animals, plants, and other organisms. The study of fossils across geological

time, how they were formed, and the evolutionary relationships between taxa

(phylogeny) are some of the most important functions of the science of paleontology.

The relative geological time scale, as developed during the 19th century, is based

largely on the fossil content of the rock strata. The development of radiometric dating

techniques in the early 20th century allowed geologists to determine the absolute age of

the various strata and the included fossils.

2. "Evolution and the Fossil Record by John Pojeta, Jr. and Dale A.

Springer."Evolution and the Fossil Record by John Pojeta, Jr. and Dale A.

Springer. N.p., n.d. Web. 01 Dec. 2014.

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The discovery of radioactivity late in the 19th century enabled scientists to

develop techniques for accurately determining the ages of fossils, rocks, and events in

Earth's history in the distant past. For example, through isotopic dating we've learned

that Cambrian fossils are about 540-500 million years old, that the oldest known fossils

are found in rocks that are about 3.8 billion years old, and that planet Earth is about 4.6

billion years old.

3."Legendary Snowmastodon Fossil Site in Colorado." ScienceDaily.

ScienceDaily, n.d. Web. 01 Dec. 2014.

For this next article, I decided to check out a modern day example to see how fossils

help us understand what is happening today as well. Four years ago, a bulldozer turned

over some bones at Ziegler Reservoir near Snowmass Village, Colorado. Scientists

were called to the scene and confirmed the bones were those of a Columbian

mammoth, setting off a frenzy of excavation, scientific analysis, and international media

attention. This dramatic and unexpected discovery culminates this month with the

publication of the Snowmastodon Project Science Volume. It was unknown to them that

the Colorado Rockies were filled with American Mastadons, and it was stated that this

information may help them better understand climate change in the American West.

4. Wilford, John Noble. "Fossil Teeth Put Humans in Europe Earlier Than

Thought." The New York Times. The New York Times, 02 Nov. 2011. Web. 30 Nov.

2014.

This was another modern day example of how fossils better our understanding of

our environment and ourselves. For this particular article, the fossils gave information

on the human species. A group of scientists discovered the oldest known skeletal

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remains of anatomically modern humans in all of Europe. They found a part of a jaw

with three teeth, and two infant teeth separately. The age was set from 41,000 to 44,000

years old, leading to speculation that early humans might have coexisted with

Neanderthals in Europe, something that many other scientists have previously doubted.

5. "Geology of Virginia | Geology of VA." Geology of Virginia | Geology of VA.

N.p., n.d. Web. 01 Dec. 2014. http://web.wm.edu/geology/virginia/vafossils/

This is a summary of fossils in the state of Virginia, including information about our state

fossil. It summarizes that the state of Virginia boasts a spectacular array of fossils—

from 540 million year old burrows (Skolithos) to one million year old Mastodon teeth.

Our state fossil, Chesapecten jeffersonius, is a large extinct species of scallop that

dates to approximately 4.5 million years ago. It was the first fossil ever described in

North America and is named after Thomas Jefferson, one of our founding fathers, and

an amateur paleontologist. A number of fossil sites in Virginia would be York River State

Park in York County, VA, Lake Matoaka Spillway in Williamsburg, VA, and many more

in Surry County and York County.

6. "The Paleontology Portal." The Paleontology Portal. N.p., n.d. Web. 01 Dec.

2014. <http://www.paleoportal.org/index.php?

globalnav=time_space§ionnav=state&name=Virginia>.

This article gave information on the Precambrian, Paleozoic, Mesozoic, and

Cenozoic rock formation in Virginia. In the Precambrian, sedimentary rocks occur in the

Blue Ridge Province of Virginia, but no fossils have been positively identified from these

deposits. Paleozoic rocks are well represented in Virginia. Episodes of deposition in

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shallow seas were interrupted by mountain-building events and subsequent periods of

erosion. The retreat of the extensive shallow seas of the Paleozoic left much of the state

exposed during the Permian and Mesozoic. In central Virginia, fossils of dinosaur

footprints, freshwater fish, and insects are found in rift basin deposits of the Triassic. In

the Cenozoic, there were massive sea level changes. Amazing numbers of fossil clams,

snails, and sand dollars can be found in these marine rocks, along with fossilized whale

bones and shark teeth.

7. Kaplan, Matt. "DNA Half Life." Nature.com. Nature Publishing Group, n.d. Web.

01 Dec. 2014. <http://www.nature.com/news/dna-has-a-521-year-half-life-1.11555>.

I was intrigued to find an article that is about DNA half-life. As one of my activities

dealt with half-life, I decided to read up on it. Palaeogeneticists led by Morten Allentoft

at the University of Copenhagen and Michael Bunce at Murdoch University in Perth,

Australia, examined 158 DNA-containing leg bones belonging to three species of extinct

giant birds called moa. The bones, which were between 600 and 8,000 years old, had

been recovered from three sites within 5 kilometers of each other, with nearly identical

preservation conditions including temperature. The researchers calculated that DNA

has a half-life of 521 years, and predicted that even in a bone at an ideal preservation

temperature of −5 ºC, effectively every bond would be destroyed after a maximum of 6.8

million years. The DNA would be too short to give enough information at roughly 1.5

million years.

8. "RELATIVE AGE." RELATIVE AGE. N.p., n.d. Web. 01 Dec. 2014.

<http://academic.brooklyn.cuny.edu/geology/leveson/core/topics/time/

froshlec8.html>.

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The next article I read summarized about the Law of Superposition. This states

that in a layered, depositional sequence (such as a series of sedimentary beds or lava

flows), the material on which any layer is deposited is older than the layer itself.

Therefore, the layers are successively younger, going from bottom to top. The article

gave illustrations of layers that listed them in numbers and placed them on top of each

other. Numbered one through five, the layers gave an illustration of how the law works.

9. Castro, Joseph. "How Do Fossils Form?" LiveScience. TechMedia

Network, 26 June 2013. Web. 01 Dec. 2014. <http://www.livescience.com/37781-

how-do-fossils-form-rocks.html>.

This article shed light on a much simpler topic of this SOL: How fossils form.

When animals, plants and other organisms die, they typically decay completely. But

sometimes, when the conditions are just right, they're preserved as fossils.Several

different physical and chemical processes create fossils. Freezing, drying and

encasement, such as in tar or resin, can create whole-body fossils that preserve bodily

tissues. These fossils represent the organisms as they were when living, but they're

very rare. There are many other kinds of fossilization that this article describes, such as

replacement, permineralization, and carbonization.

10. "People May Get Place in Geologic Time Scale : DNews." DNews. N.p.,

n.d. Web. 01 Dec. 2014.

<http://news.discovery.com/earth/rocks-fossils/anthropocene-period-humanity-

effect-earth-130716.htm>.

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The Anthropocene is the name of a proposed new geological time period

(probably an epoch) that may soon enter the official Geologic Time Scale. The

Anthropocene is defined by the human influence on Earth, where we have become a

geological force shaping the global landscape and evolution of our planet. According to

this idea, the present epoch — still known as the Holocene, which started 11,000 years

ago — would have ended somewhere between the end of 18th century and the 1950s

(when the Anthropocene began). The earlier time limit considers the increasing amount

of carbon dioxide and other greenhouse gases in Earth’s atmosphere that is mostly due

to the burning of fossil fuels for energy to power our growing industrial technology.

Activities

The articles I went through helped me to get a better idea of what I wanted for my

activities. The first activity dealt with half-life, and was based off of a lab I did in my time

at Longwood. I took small pieces of paper, and on one half I marked them green. The

idea was to put them in a bag to represent an organism. I got my roommate to shake

the bag and dump it. He kept every marked one, and took out every one not marked.

The bag would typically divide in two each time, representing half-life of an organism,

and how many half-lives can be done before he ran out of paper. He made it to 8 half-

lives, which was more than what I got in mine, but still close to an accurate depiction of

how many can be done. We found that after so many half-lives, the data became

useless or little to none.

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My next activity involved a worksheet that I had made up. In it, I drew various

layers of sediments and labeled them with letters. Under that, I put the definition of

original horizontality and law of superposition. I gave the worksheet to my roommate

and asked him to put the layers of sediments in the correct order. He was able to do so

after reading what the laws were. With no help, he labeled them one after another.

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Doing both these activities helped me to better understand what it is like teaching

this material from a teacher’s point of view. Reading the articles also gave me further

insight to how this can be used in the present to help us know ourselves and our

surroundings better. This topic was important for me, because it was a fun topic for me

to learn, and I want to make it fun for others to learn as well.