what do dolphins understand about hidden objects n.
Skip this Video
Loading SlideShow in 5 Seconds..
What do dolphins understand about hidden objects? PowerPoint Presentation
Download Presentation
What do dolphins understand about hidden objects?

Loading in 2 Seconds...

play fullscreen
1 / 38

What do dolphins understand about hidden objects? - PowerPoint PPT Presentation

  • Uploaded on

What do dolphins understand about hidden objects?. A study conducted by Kelly Jaakkola, Emily Guarino, Mandy Rodriguez, Linda Erb, and Marie Trone Presented to you by Ngoc and Adrielle. Introduction. Ability to track objects associated with spatial cognition

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'What do dolphins understand about hidden objects?' - heath

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
what do dolphins understand about hidden objects
What do dolphins understand about hidden objects?

A study conducted by Kelly Jaakkola, Emily Guarino, Mandy Rodriguez, Linda Erb, and Marie Trone

Presented to you by Ngoc and Adrielle

  • Ability to track objects associated with spatial cognition
  • Object permanence “ability to mentally represent and reason about objects that have disappeared from view”
  • Piaget-six stages of object permanence.
    • Stage 6 = ability to track movements of hidden objects
    • Marks emergence of new representational capacity.
  • Perner-invisible displacement task one of several abilities that show capacity for secondary representation.
  • Apes able to pass invisible displacement tasks.
  • Monkeys-controversial.
    • Some studies don’t control for association rules.
  • Dogs and cats unable to pass.
    • use association rules instead of true understanding.
  • Birds also controversial.
    • Method of training may result in learning association rules.
  • Cetaceans and primates both show higher cognitive abilities--like secondary representation.
  • Dolphins have ability to imitate, mirror self recognition, means-end reasoning, ability to understand symbols.
experiment 1 set up
Experiment 1—Set Up
  • Aleta, Delphi, Pandora, Pax, Rainbow, and Tanner
  • Four males, two females
  • ages 3-27 years old
  • All did regular training and public interactions
  • 3 trash cans
  • 3 Rubbermaid lids, connected with PVC bar
  • 1 stuffed toy alligator
  • 1 opaque PVC cylinder
displacement conditions
Displacement conditions
  • Single visible displacement—put object in one bucket only
  • Double visible displacement—put object in one bucket, then move to a second
  • Invisible displacement—put object in cylinder, cylinder in bucket, and remove cylinder without object
  • 1 week per condition
  • 2 sessions per condition, over 2 consecutive days
  • 6 choice trials and 3 errorless trials per session
  • Trial order randomized
  • Refresher session day before test
  • Object is visible from bucket
  • One bucket, object is entirely hidden
  • Introduce object and signal
  • Intro buckets, then lids
  • Errorless trials
  • Hider calls dolphin
  • Hide object
  • Put lid on
  • Hider gets the Asker
  • Ask question verbally and with hand signal
  • Dolphin chooses (with rostrum, or snout)
  • Removes lid
    • Correct--pulls object out, blows whistle, reward
    • Incorrect--asker shows empty bucket and finds correct bucket to show to the dolphin

Trial aborted if:


Reset if another dolphin comes over

If another behavior response or no response, then signal is given again

  • Dolphin swims away
  • Touched bucket before signal
  • Touched something else
  • If 3 aborted trials in a row, trial is skipped and coded incorrect
  • Choice is indicated by dolphin touching rostrum (snout) to the bucket, lid, or the displacement cylinder
  • Video recordings used to
    • double check results
    • second experimenter to independently code (100%) reliability
results and accuracy
Results and Accuracy
  • Motivation was high
  • *Rainbow’s data omitted from this trial—still significant results
  • Overall averages
    • Single displacement: above chance, P= 0.05
    • Double displacement: no success, P= 0.158
    • Invisible displacement: no success, P= 0.187
order effects and strategies
Order Effects and Strategies

Order Effects

Individual Strategies

Correct responding

First bucket in which object was placed

Cylinder, or bucket closest to cylinder

Favored bucket– 9 out of 12 selections

For 1.-3., 8 out of 12 selections indicate use of a strategy

  • Single displacement first
    • typically did better
  • Perhaps large leap from testing to training?
  • Overall average:
    • Single: pass
    • Double: fail
    • Invisible: fail

Dolphins do not typically reach for things.

experiment 2 set up
Experiment 2—Set Up
  • AJ, Calusa, Pax*, and Tanner* (Pax and Tanner from Exper. 1
  • 1 female, 3 males
  • ages 4-18 years old
  • All did regular training and public interactions
  • Same trash cans and toy alligator
  • One large lid made from PVC pipe and canvas
  • Same cylinder

Displacement conditions


3 conditions over 3 days

Invisible and Transposition counterbalanced

Vanishing cylinder test within 5 days after

Four trials for each bucket location

12 trials per session

2 sessions per day

  • Double visible
  • Invisible
  • Transposition
  • Vanishing cylinder—same as 2., but remove cylinder from testing area
  • Pax and Tanner—refresher from Experiment 1
  • New subjects given same basic training
  • Changes to training
    • No errorless trials
    • Objects hidden completely
    • Introduce different lid

Same as Experiment 1, except for:

  • Incorrect bucket—asker removed object from correct bucket; did not show empty bucket
  • If dolphin was distracted, trial was aborted, then “timeout,” and trial was put at the end of sessions
    • 3 skipped trials = end session
results and accuracy1
Results and Accuracy
  • Motivation was high
  • Second experimenter coded, 99% reliability
  • Overall averages
    • Double displacement: above chance, P= 0.004
    • Invisible displacement: no success, P= 0.0464
    • transposition: no success, P= 0.760
    • No sig. main effect of previous experience, P=0.1888
effects and strategies
Effects and Strategies

Effect of cylinder presence

Individual Strategies

Same as Experiment 1 plus

Selecting moved bucket

Only one instance

  • Dolphins new to the study
    • Still a chance performance
  • Experienced dolphins
    • Much better without cylinder present
  • Overall average:
    • Double: pass
    • Invisible: fail
    • Transposition: fail

Surprising performance: no containers in natural environment

experiment 3
Experiment 3
  • Same dolphins as Experiment 2.
  • Same buckets and lids.
  • Same procedure for trials.
  • Toy mouse (small enough to fit in hands).
displacement conditions1
Displacement Conditions
  • Hand displacement
  • Drop-first condition
  • Drop-last condition
  • Dolphins performed above chance only for hand displacement (P < 0.001).
  • Not drop-first (P=0.215) or drop-last (P=0.058).
  • More naturalistic
  • All dolphins able to complete to pass this invisible displacement condition.
  • They may be selecting the last bucket the experimenter pays attention to.
  • Unable to determine bucket with hidden object if experimenter pays attention to more than one bucket.
experiment 4
Experiment 4
  • Same dolphins, same objects, same procedure.
  • Same displacement condition as in Experiments 1 & 2 but object is placed in 1st bucket that experimenter visits.
  • Control for possibility that dolphins are choosing last bucket that trainer touched.
  • Dolphins performed above chance (P=0.011).
  • Compared to double visible displacement task from Experiment 2.
    • Visible drop-first and drop-last comparison
    • Not significant (P=0.89).
  • Success on visible displacement not due to using a simple response strategy.
overall results
Overall Results
  • Visible displacement: pass
  • Tracking hidden objects: fail
  • Invisible displacement task: ??
    • With hands used instead of cylinder, performance was better
  • In past research, “dolphins are proficient in tasks requiring symbolic or secondary representation.”
  • If Stage 6 object permanence=symbolic/secondary representation, why did the dolphins fail at these tasks?
possible reason 1 experiment is not suited to display ability
Possible Reason 1--Experiment is not suited to display ability
  • Different from other permanence studies
    • Used explicitly trained responses
  • Perhaps dolphins did not understand task
    • Only difficulty was with hidden movement; they knew to seek object
possible reason 2 perceptual disadvantage
Possible Reason 2—Perceptual disadvantage
  • No echolocation
  • Difficulty perceiving object details
    • No, because difficulty was when objects were not perceivable
possible reason 3 dolphins do not have these abilities
Possible Reason 3—Dolphins do not have these abilities
  • Not likely
  • Shown evidence of secondary representation in other research
secondary representation support
Secondary Representation--Support
  • Imitation
  • Mirror self-recognition: mark test
  • Means-ends reasoning
  • Attributing attention: follow trainers’ gaze
  • Understanding external representations
    • Televised images
    • Yes/no questions
questions raised
Questions Raised




Visible drop-first test

Removing cylinder did not improve success

  • Higher memory load?
  • Distracting movements?
  • Inhibit preferred responses?

Suggestion: test with visually and acoustically opaque occluders instead of containers

  • Success with visible displacement task, not invisible or transposition
    • Very puzzling, considering other success
    • Can do other tasks that are not part of natural behaviors
  • Perhaps a lack of understanding containers or experience with tracking an object hidden from sight and echolocation
    • Maybe echolocation helps track hidden objects