Using hand trowels, students can start slowly removing
the overburden in the area to determine the extent of the area
that contains bones. When the students reach the harder material in
your matrix, they should use whisk brooms to clear the remaining loose
material.
The next step involves exposing, but not removing, the bones
contained in the matrix. Awls and whisk brooms will be necessary for
this step. As the matrix reveals more of its hidden "treasure" one or more students should
draw a detailed sketch/map of the location of each bone
contained in the matrix. Work should continue on revealing the bones
and determining the boundaries of the find.
Once this has all
been completed, the students should dig a trench approximately 16 inches wide
and a foot deep around the matrix. This allows the matrix containing the
bones to be isolated from the surrounding material. Students should then
undercut material from around and beneath the sides of the matrix. This is
referred to as pedestaling. What remains should resemble a squat, flat-topped mushroom.
Have the students, under the supervision of an adult prepare
the plaster. Soak the strips of burlap in the plaster mix and spread them out on
the top of the matrix. The plaster-covered strips should be added until
the entire top and sides of the matrix are covered. The idea is to build a
jacket for the matrix that will provide protection and allow the specimen to be
safely transported. Students should wash off the plaster from their
skin at the site. Allow the jacket to harden.
Lunch and a
recreational activity should provide the necessary time needed for the plaster
to set. Once the plaster has set, the matrix encased in its plaster jacket
should carefully be flipped over so that it can be lifted and transported.
Once all the teams have removed their finds the process of making a
display of each begins. Using the sketch/site map, students will be able
to expose the entire specimen in the classroom. The use of awls and old
dental tools will be helpful. The final product will be the bone(s)
displayed in the matrix. The surface displayed will actually be the underside of
each bone found and exposed at the field site.
Teacher
Notes: This is a detailed lesson and requires a good deal
of preparation on the part of the teacher. Collection and preparation
of bones, locating a good site (a local quarry would be ideal), preparing
a matrix with bones, enlisting capable and reliable parents/supervisors,
and all the other normal effort and planning that goes into a successful
field trip are necessary for this activity. However, the opportunity
for students to do some "real science" and gain insights into what is required of paleontologists in order to further study prehistoric life are
well worth the effort and the planning!
If you put the word out
to students early in the year that you are looking for animal bones, they'll
start arriving in your classroom shortly. Stress the fact that these
should be old or you may end up with bones complete with odoriferous material
attached. In this case some preparation will be necessary.
Your choice of site will dictate how you plant your specimens. You will need to spend time burying the major portion of each specimen, but avoid burying the entire matrix. The exposed bones should take some work finding, but should not be impossible. Prior knowledge of your age group and specific students will dictate the level of difficulty for this activity. Remind students that prospecting takes time. The bones are there to be found. In an actual paleontology field experience there are no assurances.
Vocabulary:
A.8.6
B.8.4
E.8.5
Interdisciplinary Connections:
Wisconsin State Science Standards:
A.8.4
http://www.dpi.state.wi.us/dpi/standards/scia8.html
Collect evidence to show that models developed as explanations for events were (and are) based on
the evidence available to scientists at the time
http://www.dpi.state.wi.us/dpi/standards/scia8.html
Use models and
explanations to predict actions and events in the natural world
B.8.3
http://www.dpi.state.wi.us/dpi/standards/scib8.html
Explain how the
general rules of science apply to the development and use of evidence in
science investigations, model-making, and applications
http://www.dpi.state.wi.us/dpi/standards/scib8.html
Describe types of
reasoning and evidence used outside of science to draw conclusions about the
natural world
C.8.1
http://www.dpi.state.wi.us/dpi/standards/scic8.html
Identify questions
they can investigate using resources and equipment they have
available
C.8.2
http://www.dpi.state.wi.us/dpi/standards/scic8.html
Identify data and
locate sources of information including their own records to answer the
questions being investigated
C.8.3
http://www.dpi.state.wi.us/dpi/standards/scic8.html
Design and safely
conduct investigations that provide reliable quantitative or qualitative
data, as appropriate, to answer their questions
C.8.4
http://www.dpi.state.wi.us/dpi/standards/scic8.html
Use inferences to
help decide possible results of their investigations, use observations to
check their inferences
C.8.5
http://www.dpi.state.wi.us/dpi/standards/scic8.html
Use accepted
scientific knowledge, models, and theories to explain their results and to
raise further questions about their investigations
C.8.6
http://www.dpi.state.wi.us/dpi/standards/scic8.html
State what they have
learned from investigations, relating their inferences to scientific
knowledge and to data they have collected
C.8.7
http://www.dpi.state.wi.us/dpi/standards/scic8.html
Explain their data
and conclusions in ways that allow an audience to understand questions they
selected for investigation and the answers they have developed
C.8.8
http://www.dpi.state.wi.us/dpi/standards/scic8.html
Use computer software
and other technologies to organize, process, and present their data
C.8.9
http://www.dpi.state.wi.us/dpi/standards/scic8.html
Evaluate, explain,
and defend the validity of questions, hypothesis, and conclusions to their investigations
C.8.10
http://www.dpi.state.wi.us/dpi/standards/scic8.html
Discuss the
importance of their results and implications of their work with peers,
teachers and other adults
C.8.11
http://www.dpi.state.wi.us/dpi/standards/scic8.html
Raise further
questions which still need to be answered
http://www.dpi.state.wi.us/dpi/standards/scie8.html
Analyze the geologic
and life history of the earth, including change over time, using various
forms of scientific evidence
G.8.1
http://www.dpi.state.wi.us/dpi/standards/scig8.html
Identify and
investigate the skills people need for a career in science or technology and
identify the academic courses that a person pursuing such a career would
need