Chapter 7 - Experiments

Question 1

Juncos - RQ

Answer 1

Does Age affect feeding behaviour?

Question 2

Juncos - Hypothesis + Prediction

Answer 2

H: As birds age they should have more experience handling food
P: Older birds should handle food faster than younger birds

Question 3

Juncos - Methods

Answer 3

-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

Question 4

Juncos - Results + Conclusion

Answer 4

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

Question 5

Salamanders + Foraging

Answer 5

Salamander neonates can recognize, attack, and
capture prey within one week of hatching, without prior experience

Question 6

Salamanders + RQ

Answer 6

Does their foraging efficiency improve with experience?
- examined predatory hunting skills of 2 week lab individuals that had no opportunity to forage

Question 7

Salamanders + Methods

Answer 7

• 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

Question 8

Salamanders + Results

Answer 8

• 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

Question 9

Green Frogs + RQ

Answer 9

Does the dear enemy hypothesis explain aggression in territorial green frogs?

Question 10

Green Frogs - Hypothesis + prediction

Answer 10

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

Question 11

Green Frogs + Methods

Answer 11

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 &

Question 12

Green Frogs + Results

Answer 12

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

Question 13

Green Frogs + Conclusion

Answer 13

Conclusion: The dear enemy hypothesis is supported Focal males habituated to stranger calls

Question 14

Chicks + RQ

Answer 14

Is the release of neurotransmitters from the presynaptic neuron associated with imprinting learning?

Question 15

Chicks + Methods

Answer 15

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)

Question 16

Chicks + Results

Answer 16

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

Question 17

Chicks + Conclusion

Answer 17

Neurotransmitters appear to play a role in imprinting

Question 18

Mice + RQ

Answer 18

Is dendritic spine formation associated with learning in mice? (

Question 19

Mice + Methods

Answer 19

Controls: no training
Experimental: mice trained to run on a rotating rod
Measured formation of new dendritic spines

Question 20

Mice + Result

Answer 20

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)

Question 21

Mice + Conclusion

Answer 21

Mice that developed more dendritic spines performed better on the rotorod - formation of dendritic spines is associated with learning

Question 22

Quail + RQ

Answer 22

: How does learning affect fitness?

Question 23

Quail + Hypothesis + Prediction

Answer 23

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

Question 24

Quail + Methods

Answer 24

• 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

Question 25

Quail + results

Answer 25

CS+ performed better

Conclusion: Pavlovian conditioning can affect fitness

Question 26

Macaques + RQ

Answer 26

How quickly can individuals learn to overcome an innate preference?

Question 27

Macaques + Methods

Answer 27

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

Question 28

Macaques + Results

Answer 28

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”)

Question 29

Macaques + Conclusion

Answer 29

There is tremendous variation in learning curves

Question 30

Precocial Birds (Chicks) + RQ

Answer 30

How do chicks learn the best plants to feed on?

Question 31

Chicks (2) + Hypothesis + Prediction

Answer 31

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

Question 32

Chicks (2) + Methods

Answer 32

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

Question 33

Chicks (2) + Results

Answer 33

Certain foods that were consumed in high amount - high % in diet
Food calls and Foot diet was quite similar in trend

Question 34

Chicks (2) + Conclusion

Answer 34

Chicks learn the most nutritious plants from their mother’s food calls

Question 35

Sticklebacks + RQ

Answer 35

Do animals use local enhancement or public information to assess patch quality?

Question 36

Sticklebacks + Social Learning

Answer 36

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

Question 37

Sticklebacks + Methods

Answer 37

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

Question 38

Stickleback + Results

Answer 38

Number - goes to the higher number
Quality - less demonstrators still pick high quailtiy patch