Chapter 7 - Experiments Flashcards
Juncos - RQ
Does Age affect feeding behaviour?
Juncos - Hypothesis + Prediction
H: As birds age they should have more experience handling food
P: Older birds should handle food faster than younger birds
Juncos - Methods
-Mealworms cut into small or large pieces
-Smaller pieces easier to mandibulate
-Recorded handling times (time from first contact until consumption) of recently fledged, young, and older juveniles, as well as adults
Juncos - Results + Conclusion
Result: Adults had the lowest handling times and the highest energy intake rate
Conclusion: Older, more experienced birds had learned how to best handle insect prey
Salamanders + Foraging
Salamander neonates can recognize, attack, and
capture prey within one week of hatching, without prior experience
Salamanders + RQ
Does their foraging efficiency improve with experience?
- examined predatory hunting skills of 2 week lab individuals that had no opportunity to forage
Salamanders + Methods
- 3 feeding trials were separated by about 14 days = digestion period
-Feeding efficiency : presented 4 termites + recorded capture attempts snapping of jaw), successful captures, + # of prey that escaped → quantified # of prey captures + foraging accuracy
Salamanders + Results
- captured few prey in 1st trial → improved in 2, 3
- Indiv. rapidly learn to forage in a more efficient manner → gain experience = enhances → survivorship in the wild
Green Frogs + RQ
Does the dear enemy hypothesis explain aggression in territorial green frogs?
Green Frogs - Hypothesis + prediction
Hypothesis:
The level of aggression to a conspecific will vary with familiarity due to habituation
Prediction:
There should be a decrease in their response to a new rival’s vocalization after an initial aggressive response
Green Frogs + Methods
Studied males at four ponds
Created synthesized calls of two males
Frequency of 350Hz
Frequency of 450Hz
Playback of calls from speakers 1-2 m
from focal calling male
Recorded focal male response calls &
Green Frogs + Results
1) 350Hz - Focal males decrease movement toward calls of both frequencies after first broadcast of calls
2) 450 Hz - Focal males switched from advertisement to lower frequency aggressive calls after playback of calls
Vocalization of Focal Males: advertising males switch to lower frequency aggressive call after intruder appears
Green Frogs + Conclusion
Conclusion: The dear enemy hypothesis is supported Focal males habituated to stranger calls
Chicks + RQ
Is the release of neurotransmitters from the presynaptic neuron associated with imprinting learning?
Chicks + Methods
Control (not visual stimulus) Vs. Exp group (trained w/ visual stimulus - bod / blue cylinder)
Trained on running wheel
Measured movement toward stimulus
Measured amino acid transmitters in intermediate and medial portions of hyperstriatum ventrale (IMHV)
Chicks + Results
Glutamate Release + Training = Trained chicks had higher glutamate levels
Preference Score: Calculated by placing two objects in front of the chick while on the wheel (divide amount of running to imprinted object / total running time)
(imprinted object vs. new object)
Chicks with higher preference scores had higher amount of GABA in their brain
Chicks + Conclusion
Neurotransmitters appear to play a role in imprinting
Mice + RQ
Is dendritic spine formation associated with learning in mice? (
Mice + Methods
Controls: no training
Experimental: mice trained to run on a rotating rod
Measured formation of new dendritic spines
Mice + Result
Result: Mice that learned new skill (running on rotorod revolution / min they could achieve) had higher levels of dendritic spine formation
- trained indiv. had the highest new spine formation (adult+young)
Mice + Conclusion
Mice that developed more dendritic spines performed better on the rotorod - formation of dendritic spines is associated with learning
Quail + RQ
: How does learning affect fitness?
Quail + Hypothesis + Prediction
Hypothesis: Individuals can benefit by learning to associate environmental cues (a place) with mating opportunities
Prediction: Reproductive success will be higher in the condition where individuals learned that mating often occurs
Quail + Methods
- days 1-5 - training
- CS+ = had experience of mating/prior experience (-) = none
- On cage of wire, one w/ plastic
-males had a opper. in same trials
Quail + results
CS+ performed better
Conclusion: Pavlovian conditioning can affect fitness
Macaques + RQ
How quickly can individuals learn to overcome an innate preference?
Macaques + Methods
Training
Offered six subjects choice of one or four peanut halves
If chose one, subject received four peanut halves
If chose four, subject received one peanut half
Measured how quickly individuals learned to select the smaller quantity
Given a choice between smaller and larger quantities
Most animals have innate preference for larger quantities
One action is providing more reward
A more positive reinforcing outcome
Macaques + Results
Fast learner = fast reduction in errors
Slow learners - more trials before they become prefieicent
All showed strong initial preference for “four”
All eventually learned to make the choice that provided the most food (“one”)
Macaques + Conclusion
There is tremendous variation in learning curves
Precocial Birds (Chicks) + RQ
How do chicks learn the best plants to feed on?
Chicks (2) + Hypothesis + Prediction
Hypothesis: Chicks can learn to identify important food plants from their mother’s food calls
Prediction: Chicks should primarily eat foods
associated with their mother’s food calls
Chicks (2) + Methods
Observed 12 hens and their broods
Recorded food eaten by hen and brood
Recorded all food calls given by hen and the food plant associated with the call
Chicks (2) + Results
Certain foods that were consumed in high amount - high % in diet
Food calls and Foot diet was quite similar in trend
Chicks (2) + Conclusion
Chicks learn the most nutritious plants from their mother’s food calls
Sticklebacks + RQ
Do animals use local enhancement or public information to assess patch quality?
Sticklebacks + Social Learning
Local Enhancement Available: High number of individuals could indicate the best patch
Public Information Available: Observation of feeding success more important than number of individuals
Numbers vs Quality
Sticklebacks + Methods
Local enhancement experiment:
Test fish can observe demonstrator fish – six at one patch and two at the other (no food)
Test fish can observe demonstrator fish (six at poor patch and two at rich patch) foraging (food present)
Quality vs Numbers
Removed demonstrators
Measured amount of time test fish spent near patches
Stickleback + Results
Number - goes to the higher number
Quality - less demonstrators still pick high quailtiy patch
