Of BIO110's three student learning objectives--
you can find these in the syllabus--two of
them directly concern the ability of students
to connect experimentation with conclusions
as a pathway to building scientific knowledge.
It's not that we expect every BIO110 student
to become career scientific researchers--some
of you will, but this is not a class to train
students for academic research careers.
Every student, however, needs to have the
same basic tools of inductive and deductive
logic that are employed by professional scientists.
Given several pieces of information what can
be legitimately concluded, and--maybe even
more importantly--what kinds of things would
not be unequivocally supported by the information
provided?
What is it about certain results that constitute
unequivocal support for a given conclusion?
This is science.
It's also what thinking citizens do as they
process the flow of information that comes
into their awareness through the media as
well as by direct observation.
The opposite of processing information and
reaching defensible and well-thought out conclusions
would be to accept statements without requiring
validation by facts--this is non-science,
and it involves no thinking at all.
A demonstrably false statement is not made
any more valid if it is repeated loudly and
often.
In fact, this is the opposite of science,
and to the extent that our knowledge of the
true nature of the universe is a good thing
in the sense that it informs and speeds our
progress towards greater well-being or some
other generally agreed-upon goal, that would
mean logically that it's a truly bad thing
for people to accept unsupported claims.
"Thinking like a scientist" is thus a worthy
aspiration for every person.
Period.
It's not the easiest thing you'll ever do--it
requires discipline and effort, and having
a bit of training doesn't hurt either.
And here is where this lab comes in.
As in the previous lab's video, there will
be points here where the playback will pause
for you to answer questions, and this will
constitute your pre-lab quiz.
Some of the questions will be drawn from information
in the handout--not necessarily content that
is spoken or shown in this video.
You should read through the handout before
moving onward with this video.
The need for "discipline" might have been
evident as you read through the introduction.
How are an observation of a phenomenon, a
question asked about the phenomenon, and a
hypothesis to explain the phenomenon--how
are these three things both related and different?
One person may find the distinction between
these things to be "pointless attention to
detail," while another person considers this
to be "discipline."
And for understanding the scientific method,
you're better off erring toward the latter.
Differences that might seem trivial when viewed
casually actually turn out to be salient when
there is a need for greater rigor, and this
is an example of that extra effort required
in order to think like a scientist.
You'll have the opportunity to practice your
skills in this area at various points in our
lab exercise.
But more than what you're doing in class this
week, you might be practicing these skills
on your own based on the things you encounter
within your own orbit.
What is the observation?
What is the question?
What is the hypothesized explanation for the
phenomenon?
Is the hypothesis testable?
What kind of experiment would be useful for
evaluating the validity of the hypothesis?
What kind of result is needed to support the
hypothesis?
What kind of result would clearly refute the
hypothesis?
Can you describe an experiment with manipulated
variables that would be able to support the
hypothesis with some results and refute the
hypothesis with different results?
What kinds of confounding variables might
be problematic for your experimental design?
How might those confounding variables be controlled?
The main focus of this lab is to develop your
ability to address all of the questions I
just listed.
But really the task at hand requires nothing
more than what you carry around with you at
all times.
You certainly don't need to restrict this
kind of thinking to just when you're in a
science lab--this is an exercise that you
should continue on your own time, outside
of class, for the remainder of the semester
and the remainder of your life.
But for now your immediate goal is to be able
to take any real-world phenomenon that your
instructor gives you and identify a potential
explanation--and this would be your hypothesis.
For instance, I could tell you that the 1,000
young fish put into a lake were all the same
size initially, but they have been growing
at different rates.
This would be the observation.
You should be able to come up with a hypothesized
explanation for the observation such as, "the
fish are getting unequal amounts of food because
some are more aggressive than others," or
"the two sexes of the fish grow at different
rates" or ... come up with your own idea here.
And then you should be able to follow that
up with an experimental protocol for evaluating
your hypothesis, delineating what results
would support the hypothesis as well as what
results would refute the hypothesis.
The next task in this week's lab activity
is to generate and to interpret graphical
representations of data.
We'll start with the data we gathered last
week-- the volume accuracy results and the
human measurements data set.
As we're thinking about graphing, one issue
that stands out front and center is the determination
of which variable is "independent" and which
is "dependent."
Identifying which is which is important especially
now because you almost always want to have
the independent variable on the horizontal
axis.
Graphs are used to visually depict a pattern
(or an absence of a pattern) in the data.
By looking at a graph with a horizontal and
a vertical axis, you should be able to say
first of all whether or not there is a pattern
or relationship between the two variables.
If there is a pattern evident, what is it,
and what does it suggest?
A lot of this week's activities will require
collaboration with the other members in your
work group.
Ideally everyone in your group will have done
their part in diligently preparing for the
lab--having completed this video and having
read through the written instructions of the
lab carefully.
Even under such ideal conditions, there will
likely still be some differences in perspective
between the members of your group.
If you think one way about a particular answer
and other people in your group have different
ideas from yours, you should discuss.
Is it possible for different answers to be
correct?
Why, yes.
When it comes to experimental design there
are usually several different ways to approach
any given question, and it's a good thing
to see other ideas and to consider the merits
they might have.
Given this kind of flexibility, is it even
possible to have a bad suggestion?
Oh yeah.
There are many, many more ways to be wrong
than right.
If there is a bad idea being aired in your
group, you don't need to shout anyone down,
but the misguided person needs to be redirected,
and in the context of a group discussion that
responsibility falls to those members of the
group who can explain where the faults are
in that misguided person's thinking.
You should also remain open to the possibility
that this person is actually the one with
the correct picture.
If they can validate their thinking with sound
reasoning, it might be that you end up deciding
that you were the one in need of some re-direction!
If all of the questions I gave you were going
to be easy and with one obvious answer, there
would be no need for group discussion.
Don't expect a lot of those easy questions
in this lab class.
The greater the challenge, the more the group
needs to work together with substantive contributions
from all of its members.
BTW, don't get too attached to your lab partner
or your lab group.
I'll be re-assigning students to new groups
every few weeks.
Over the semester you'll be working closely
with most everybody that we have in class.
The last thing we do this week is to work
through an entire experimental sequence starting
with an observation which is provided to you,
and from which you and your group move through
all the steps of experimental design, the
actual experimentation, and ending up with
graphical representations of your results
and conclusions.
As always, everything we do should be recorded
in your lab notes.
