Lesson 1 Flashcards
what is animal bahavior
any internally coordinated, externally visivle pattern of activity that responds to changing external internal conditions
Niko Tinbergen
- pointed out that behavioral biologists need to answer all kinds of questions
proximate questions
mechanistic questions and developmental questions
mechanistic questions
how does the animal accomplish the task? can also include physiological questions
developmental questions
how does the behavior develop over the animal’s lifetime - learned? innate?
ultimate questions
(evolutionary questions)
- surival value (adaptive value)
- how did it evolve? phylogenty
example of a proximate question for the mass-nesting of olive ridley sea turtles in costa rica
- how do you know that they are supposed to go to the particular beach?
- how do they know it is time to leave their feeding areas?
ultimate questions about the turtles
why do they do this crazy thing? what is the adaptive value?
research hypothesis - informal
Explanation that allows us to make a
testable prediction
formal hypothesis
alternate and null
alternate hypothesis
Statistical hypothesis that the
proposed explanation for observations
does have a significant effect
null hypothesis
Statistical hypothesis that observations
result from chance
Research hypothesis (the big idea) - turtles
Maybe turtles find the beach using
their sense of smell
Alternate hypothesis (something
testable)
Turtles will swim towards a source that
smells like that particular beach
null hypothesis ( what statistics actually test for)
Smells have no effect on the course
that turtles set
THE SCIENTIFIC
METHOD: A BRIEF WORD
ABOUT STATISTICS
In a statistical test, we usually
determine a probability or “p-
value” and by convention look
to see if p<0.05.
That is, is the chance of the
null hypothesis being true less
than 5%?
That would mean that the
chance of the ‘alternate
hypothesis’ being true is
greater than 95%!
ethogram
Formal description or inventory of an
animal’s behavior
time budget
A summary of the total time and
relative frequency of different behaviors
of an individual
Research question: – elephants
What
behaviors do captive Asian
elephants exhibit? (Rees 2009)
Elephant ethograms methods:
-Studied Asian elephants (Elephas
maximus) at zoo
- Recorded behavior every five
minutes for an entire day once a
week for 11 months
-This is one of the few sorts of studies
that don’t use statistics to test
hypotheses – but can lead to a
statistical analysis as we shall see
results: elephant
Elephants spent about one-quarter of their time feeding
Stereotypic behavior (thought to indicate boredom) negatively
correlated with feeding behavior – can demonstrate statistically
A series of experiments performed in the 1790s by
Spallanzani:
- how do night-flying owls and bats find their way in the dark
SPALLANZANI’S 1ST EXPERIMENT
(manipulation and result)
Manipulation: place owls in
complete darkness and test
flying ability
Result: owls could not fly well
compared to controls (owls
that had light for vision)
Conclusion: Conclusion: owls need sight
for flight
SPALLANZANI’S 2ND EXPERIMENT
- Manipulation: place bats in
complete darkness and test flying
ability - Result: bats flew fine when
compared to controls (bats in light) - Conclusion: bats don’t need sight
for flight
SPALLANZANI’S 3RD EXPERIMENT
- Manipulation: put black hoods on
bats and test flying ability (was
worried not dark enough) - Result: black-hooded bats couldn’t
fly - Conclusion: bats need sight for
flight
SPALLANZANI’S 4TH EXPERIMENT
- Manipulation: put transparent
hoods on bats and test flying ability
(testing if hood itself had effect) - Result: clear-hooded bats couldn’t
fly as well as controls - Conclusion: the hood was the
trouble whether light got through or
not!
SPALLANZANI’S 5TH EXPERIMENT
- Manipulation: blind bats without
covering ears using opaque disks
of birdlime over the eyes - Result: blinded bats flew just fine
when compared to controls - Conclusion: bats don’t really need
sight for successful flight
SPALLANZANI’S 6TH EXPERIMENT
- Manipulation: plug ears of bats with
grease or cotton plugs and test
flying ability - Result: deafened bats did not fly
well and did not feed - Conclusion: bats need good
hearing for successful flight
SPALLANZANI’S 7TH EXPERIMENT: A CONTROL
The problem: perhaps deafened
bats were distressed by the objects
in ears and deafness had no real
role in the lack of flying
- Manipulation: place hollow brass
tubes in ears and test flying ability
with 1) tubes plugged with pine
pitch or 2) tubes unplugged - Result: bats did not fly well or feed
with plugged tubes, but were fine
with unplugged tubes
Conclusion: bats need good
hearing for successful flight; object
in ear not the problem
Manipulation: coat wings with
varnish or flour paste to interfere
with sense of touch
Compare flying and feeding
Results: varnished bats did fine
Conclusion: touch not required for
normal flying or feeding
phylogeny
The natural, evolutionary relationships
between groups of living things, inferred using a variety of techniques to establish the relative importance of various
shared features
