Biology 115 (Spring 2006) - Lab 11. Ecology and Diversity
Topics
Dissecting Owl Pellets
 Using a dichotomous key
 Constructing a food web
 Diversity and stability
Biological Diversity and Environmental Awareness
 The three domains
 The six kingdoms
 Individual responsibility for the environment
Dissecting Barn Owl Pellets
In lab today we will be using a handout developed by Ward’s, which will be given
out in lab. We will dissect barn owl pellets from different regions of the US. We will
then compare the contents of the pellets from each region. Pellets consist of the
undigested portions of prey such as bones, beaks, claws, scales, and insect exoskeletons.
These materials are orally expelled from the digestive tract as a pellet. Owls are not very
selective feeders, therefore by examining the contents of owl pellets, scientists can
estimate the diversity of available prey.
After we have dissected the pellets we will identify their contents using a
dichotomous key and will compare the contents from the different regions. We will then
construct food webs with the barn owl at the highest trophic (feeding) level and grass and
seeds at the lowest tropic level. The intermediate organisms will be those found in the
dissected pellets. We will construct a food web for each region.
Finally, we will determine which region of the US has the greater diversity and
therefore greater stability.
Biological Diversity and Environmental Awareness
It would be impossible to cover all aspects of the environment in a three-hour lab,
however this is an opportunity to help you get to know some of the great variety of
organisms that share the planet with Homo sapiens. Humans seem unquestionably to be
the dominant form of life on earth today. The impact of human activities on all life forms
though, is not all positive. We need to examine what direction we are heading in or we
will certainly ensure our own doom as well as the demise of our fellow earthlings. There
is much we as individuals can do to redirect energy, money, and power in ways that will
maintain air and water quality, and best use available resources for the good of all. As
human population increases, each of us must accept the role of caretaker, or risk the
quality of life as we know it.
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A Survey of Life: The Three Domains
There is still a great deal of discussion amongst biologists regarding the taxonomy
of life. However, most biologists now accept the three domain system. There are two
prokaryotic domains, the Archaea and the Bacteria and one eukaryotic domain, the
Eukarya. As you examine the kingdoms on display in the lab, determine to which domain
they belong.
 Fill in the table of differences between the prokaryotes and eukaryotes below:
Structure
Prokaryotes
Eukaryotes
A survey of Life: The Six Kingdoms
There is still a great deal of debate amongst biologists about the classification of
organisms at the kingdom level. Basically, it is a work in progress. Until recently, most
biologists accepted the five kingdom system. However, new methods such as comparing
DNA sequences between organisms, have revolutionized the field. Many biologists now
follow the six kingdom system of Woese. We will use this system in lab today. As you
observe the kingdoms on display, pay attention to the diversity of life on the planet. Over
1 million species have been identified, and it is possible that there may be up to 10
million different species alive today. Within each kingdom, organisms are further classed
into phyla (Protista and Animalia) or Divisions (Fungi and Plantae). Answer the
questions at each station. Take your time. Walk around and learn about some of the
organisms that share the biosphere (earth) with you.
 Name the six kingdoms, and include the basic characteristics that define the members
of each.
Kingdom Name
Characteristics
a.___________________
________________________________________
b.___________________
________________________________________
c.___________________
________________________________________
d.___________________
________________________________________
e.___________________
________________________________________
f.___________________
________________________________________
 List four members (common names OK) of each of the kingdoms (except
Archaebacteria) in the order listed above.
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a. _________________ ________________ _______________ ________________
b. _________________ ________________ _______________ ________________
c. _________________ ________________ _______________ ________________
d. _________________ ________________ _______________ ________________
e. _________________ ________________ _______________ ________________
f. _________________ _________________ _______________ _________________
 To what kingdom does Homo sapiens belong? ___________________________
 List four phyla within Kingdom Animalia, and give a member (common names OK)
of each phylum.
Phylum
Organism
a. ___________________
______________________
b. ___________________
______________________
c. ___________________
______________________
d. ___________________
______________________
 Let’s say you were an alien that just landed on Earth, and you knew about our 6
Kingdom classification system. You encounter an organism that produces its own
food, and is multicellular. In what kingdom would you classify it? _______________
 In what kingdom would you classify a unicellular organism that made its own food?
_________________________
 In what kingdom(s) would you classify a multicellular organism, if you had no idea as
to how it got its nutrition? _________________________________
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What the Individual (YOU) Can Do
a. Bike or walk to places if possible
b. Carpool or use public transportation
c. When driving, don’t speed, and keep your tires inflated properly. This saves gas.
Also, avoid cars with air conditioners - the refrigerants used in them are a major
source of chlorofluorocarbons in the atmosphere if they leak when the cars are
eventually junked.
d. RECYCLE! Take the time to separate your waste, and recycle it properly. Also, buy
recycled products. That completes the cycle. You haven’t truly recycled until you
have bought recycled products.
e. When going to the store, take your own bags, or ask for paper rather than plastic bags.
f. Buy products (juices, eggs, etc.) that are in cardboard cartons or glass rather than
Styrofoam or plastic. You should probably stick to plastic for milk though. Dioxin, a
toxic substance, has been found in milk from cardboard cartons.
g. When going to fast food places, keep and re-use the plastic silverware. Also, ask for
orders without the Styrofoam if you have a little extra time. If enough people do this,
the restaurants will have to change their packaging. This would be very good,
Styrofoam production and burning both damage the ozone layer.
h. Aerosols are not good, even if they do not contain fluorocarbons.
i. In the kitchen, use sponges rather than paper towels to wipe up spills. Also, cloth
rather than paper napkins will not only impress your guests, they save trees!
j. You’ve heard this one, TURN OFF LIGHTS, RADIOS, AND TV when you aren’t
using them. A major source of pollution is the burning of fossil fuels (especially coal)
to generate electricity. Plus, it will cut your electric bill.
k. Reduce the amount of junk mail you get. Write to Direct Marketing Association, 6
East 43rd St., New York, NY 10017 and ask to be eliminated from the lists they sell to
companies.
l. Plant trees. They use carbon dioxide for photosynthesis and in the process, produce
oxygen.
m. Get involved in ecology clubs, associations, or recycling committees.
n. Vote for politicians who are environmentally oriented.
Got any others??? Let me know.
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