Transcript intro - hovanscience

Ecology
Introduction to Ecology
Why are you here?
Teaching children about the natural world should be treated
as one of the most important events in their lives.
--Thomas Berry
Global and Local Environmental Issues
• Human Population Growth
• Water Quality and Supply
– Surface
– Ground
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Degradation of Soils
Air Quality
Species Diversity
Invasive Species
Land Use
Post-911 Ecology
Hierarchy of Biological Systems
Krohne, D.T. General Ecology. 2nd
Edition.Pacific Grove, CA.
Brooks/Cole. 2001. p. 8
What is ecology?
• Ecology – a study of the interaction
between organisms and their
environment.
• Branches:
– Molecular
– Physiological
– Genetic
– Autoecology
– Population
– Community
– Ecosystem*
– Systems / Landscape
Allied Sciences
• Natural Science (qualitative
descriptions)
• Environmental Toxicology –
chemistry and physiology of
pollution
• Conservation biology – maintain
biodiversity
• Environmental Science – ecological
effects of human activities on the
environment
Allied Sciences
• Environmental Science involves
understanding:
– Ecology
– Chemistry
– Geology
– Physics
– Meteorology
– Cultural anthropology
– Sociology
– Psychology
– Cartography
– Economics
Objectives of Ecology
• Understand how the natural world
works
• Understand how human systems are
interacting with natural systems
• Accurately assess the status and
model the trends of crucial natural
systems
• Promote and follow a long-term,
sustainable relationship with the
natural world
Your WORLD
Your CHOICE
vs.
Conceptual Framework for Ecological Research
•Scientific Process
observ e
•(aka Scientific Method)
–There are various
ways to represent
the scientific method,
but all share these
basic characteristics:
Question
Hy pothesize
Research
Conduct
Experiments
Collect and
Analy ze Data
Draw
Conclusions
Conceptual Framework for Ecological Research
1. Garbage in—Garbage out
2. All Scientific Conclusions are
tentative (no vs. maybe)
3. Understanding how to do science
is far more important than
memorizing ephemeral facts.
Conceptual Framework for Ecological Research
• Science proceeds by the falsification
of alternate explanations of an
observed effect. (Krohne, 2001)
• One of these alternative
explanations (hypotheses) must be
the Null Hypothesis (H0) which states
that the observed effect is the result
of chance (No statistically significant
difference between data).
Conceptual Framework for Ecological Research
•Example: Do bats prefer to munch on a
certain size moth?
vs.
Moths
Conceptual Framework for Ecological Research
•Observations of the bats in the field show
that they prey more on big moths than little
moths.
Study of Bat Insectivory
Frequency
Conclusion?
Moths Eaten
1
2
3
Moth Size Ranking
4
Conceptual Framework for Ecological Research
•Now let’s gather some more data…
H1= Bats prefer smaller
moths
Interaction of Moth Demographics and Bat Insectivory
H2= Bats prefer large moths
Frequency
H0= Bat do not demonstrate
a moth size preference
Moths Present
Moths eaten by bats
Conclusion?
1
2
3
Moth Size Ranking
4
Reductionism vs. Holism
• Reductionism – a process in which a
system is reduced to its component
parts for the purpose of study.
• Holism – a process in which a
system is kept intact for the purpose
of studying the interaction of its
parts.
• The trick in ecological research is to
be as holistic as possible while
maintaining the reductionism
needed to be quantitative and
empirical.
Reductionism vs. Holism
•Example 1:
Wolf
predation
Deer
Reductionism vs. Holism
•Example 2:
Deer
predation
Wolf
predation
predation
competition
grazing
Moose
grazing
competition
grazing
Hares
Vegetation
Reductionism vs. Holism
• Most modern ecological research
attempts to be as quantitative as
possible.
• The higher up the hierarchy you go,
the more difficult it is to make
inferences.
• This is why comparative studies are
so valuable to ecologists.
Reductionism vs. Holism
•Emergent Properties – Phenomena that are
observable only in the complete, intact
system.
Statistical Analysis
• Various statistical tools are useful to
test the accuracy and validity of, and
correlation between collected data.
– Regression
– T-tests
– ANOVAs
• Lab: Stats and Data Sets.
• Discussion of Results
Mathematical Modeling
• Mathematical models are used in an
attempt to formulate equations that
reflect the operation of a system.
• These models are fueled by general
assumptions about the basic
operation of the system that affect
the validity of the final mathematical
model.