when do honey bees use snapshots during navigation?
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Departing Wasp. Returning Wasp. Niko Tinbergen (1938). When do honey bees use snapshots during navigation?. Bees and wasps learn information about visual landmarks near the goal Edge orientation (Srinivasan et al., 1994) Color (von Frisch, 1967; Cheng et al., 1986) - PowerPoint PPT PresentationTRANSCRIPT
When do honey bees use When do honey bees use snapshots during navigation?snapshots during navigation?
By Frank BartlettBy Frank Bartlett
Bees and wasps learn Bees and wasps learn information about visual information about visual landmarks near the goallandmarks near the goal
Edge orientation (Srinivasan et al., Edge orientation (Srinivasan et al., 1994)1994)Color (von Frisch, 1967; Cheng et Color (von Frisch, 1967; Cheng et al., 1986)al., 1986)Size (Cartwright & Collett, 1979; Size (Cartwright & Collett, 1979; Ronacher, 1998)Ronacher, 1998)Spatial relationships among multiple Spatial relationships among multiple landmarks (Cartwright & Collett, landmarks (Cartwright & Collett, 1983)1983)
How is this information How is this information subsequently used over subsequently used over successive visits?successive visits?
Snapshot template matching Snapshot template matching (Cartwright & Collett, 1983) (Cartwright & Collett, 1983)
Niko Tinbergen (1938)
Departing Wasp
Returning Wasp
What is snapshot navigation?What is snapshot navigation?
View of landmarks is memorized from the
goal
After Cartwright & Collett, 1983 Upon return the
bee steers flight by sequentially matching her
memory to the environment
Experiments revealing the Experiments revealing the contents of snapshot memoriescontents of snapshot memories
-- When a single landmark is present bees rely on retinal image size.
-- When multiple landmarks are available bees rely on the inter-landmark angles (or the spaces between landmarks)
Single Landmark
From Cartwright & Collett, 1983
Training
Distance from landmark
Landmark
Goal
3 equidistant Landmarks
Training
Landmarks
Goal
Testing the snapshot hypothesis Testing the snapshot hypothesis in a small scale arena in a small scale arena
environmentenvironment► The snapshot hypothesis makes The snapshot hypothesis makes
accurate predictions about accurate predictions about where insects should spend their where insects should spend their time searching for the goal. time searching for the goal.
Can we replicate these findings?Can we replicate these findings?
► The hypothesis also generates The hypothesis also generates predictions of flight paths to the predictions of flight paths to the goal from more distant locations.goal from more distant locations.
Do steering commands Do steering commands generated by snapshot matching generated by snapshot matching predict honey bee flight behavior predict honey bee flight behavior while en-route to a familiar goal?while en-route to a familiar goal?
This has not been tested This has not been tested explicitly.explicitly.
Training: bees visit an initial landmark configuration (60+ visits)
Testing: track with original configuration and other
landmark manipulations
The camera records bee position and body axis orientation at 60 Hz.
MethodsMethods
Search distributionsSearch distributions
Replication of Cartwright & Collett (1983)
Training
2 x
-- When a single landmark is present bees rely on retinal image size.
-- When multiple landmarks are available bees rely on the inter-landmark angles
-- These results are consistent with previous studies
Model
The model predictions were generated in Matlab based on the algorithm provided by Cartwright & Collett (1983)
Flight paths to the goal Flight paths to the goal locationlocation
Bee Flights
E
F
Bees appear to be attracted to the nearest landmark and use it as a beacon even over very short distances
ConclusionsConclusions►Search at the goalSearch at the goal
Consistent with previous findingsConsistent with previous findings►Steering from more remote Steering from more remote
locations using template matchinglocations using template matching Bee flights not consistent with model Bee flights not consistent with model
predictionspredictions Strong role of beaconsStrong role of beacons
►Consistent with other results (Fry & Consistent with other results (Fry & Wehner, 2005; Collett & Baron, 1994) but Wehner, 2005; Collett & Baron, 1994) but extended to shorter distances and more extended to shorter distances and more complex arrayscomplex arrays
►Beacon selection probably driven by visual Beacon selection probably driven by visual saliencesalience
AcknowledgmentsAcknowledgments
NSF IGERTNSF IGERT
Fred DyerFred Dyer
Steven FrySteven Fry
Mike MackMike Mack
Chris SpeilburgChris Speilburg
Yoav LittmanYoav Littman
Jenny JonesJenny Jones
Lora BramlettLora Bramlett
Kourtney TrudgenKourtney Trudgen
Lauren DavenportLauren Davenport
Short range visual navigation Short range visual navigation in flying hymenopterans in flying hymenopterans
► Bees and wasp learn Bees and wasp learn information about visual information about visual landmarks near the goallandmarks near the goal Edge orientation (Srinivasan et Edge orientation (Srinivasan et
al.; 1994)al.; 1994) Color (von Frisch, 1967; Cheng Color (von Frisch, 1967; Cheng
et al., 1986)et al., 1986) Size (Cartwright & Collett, Size (Cartwright & Collett,
1979; Ronacher, 1998)1979; Ronacher, 1998) Spatial relationships among Spatial relationships among
multiple landmarks multiple landmarks (Cartwright & Collett; 1983)(Cartwright & Collett; 1983)
► How is this information How is this information represented and represented and subsequently used over subsequently used over successive visits?successive visits? Snapshot template matching Snapshot template matching
(Cartrwright & Collett; 1983) (Cartrwright & Collett; 1983)
Niko Tinbergen (1938)
How is this information learned?How is this information learned?The turn-back-and-lookThe turn-back-and-look
Tenth VisitFirst Visit
From Lehrer, 1993
--Motion parallax cues allow bees to distinguish nearby landmarks from distant landmarks (Lehrer, 1993)
--Believed to aid in the selection and learning of the landmarks near a goal
What is snapshot navigation?What is snapshot navigation?
View of landmarks is memorized from the
goal
After Cartwright & Collett, 1983
-- Insect visual memory is thought to be comprised of a two dimensional “snapshot” that encodes the retinotopic sizes and positions of landmarks and the gaps between them.
Bee sequentially matches her
memory to the environment upon
return
Model predictions vs. Flight Model predictions vs. Flight Behavior:Behavior:
pushed off coursepushed off course
E
F
After their course is diverted by the novel landmark, bees again use the next nearest landmark as a beacon to guide flight.
Finding the matchFinding the match► Near the goal bees prefer to Near the goal bees prefer to
maintain a southern facing body maintain a southern facing body axisaxis Snapshot is probably anchored Snapshot is probably anchored
to the retina (Collett & Baron, to the retina (Collett & Baron, 1994)1994)
► Bees perform bouts of lateral flight Bees perform bouts of lateral flight during their return to the goalduring their return to the goal Probably to help bring their Probably to help bring their
memory into register with their memory into register with their current view (Collett & Reese, current view (Collett & Reese, 1997)1997)
E
F
Model predictions vs. flight Model predictions vs. flight Behavior:Behavior:
middle landmark removedmiddle landmark removed
Model predictions vs. Flight Model predictions vs. Flight Behavior:Behavior:
farthest landmark removedfarthest landmark removed
E
F
Model predictions vs. Flight Model predictions vs. Flight Behavior: Behavior: removed nearest removed nearest
landmarklandmark
E
F
Fixed body axis and scanning Fixed body axis and scanning flightsflights
2060 * 1830 * 1550
Bees preferred a southern facing body axis orientation during their first pass through the goal region
Bees rarely performed lateral scanning flights near the landmark. Circling flights were the norm.
Snapshot overviewSnapshot overview
► Insects memorize a visual template or “snapshot” of Insects memorize a visual template or “snapshot” of landmarks they experience at important locations of landmarks they experience at important locations of their environmenttheir environment
► The memory encodes the sizes and retinal locations The memory encodes the sizes and retinal locations of landmarksof landmarks
► Insects sequentially match this template to the Insects sequentially match this template to the environment upon return while maintaining environment upon return while maintaining consistent body alignmentconsistent body alignment
► Lateral scanning movement may aid the matching Lateral scanning movement may aid the matching process process
Snapshot overviewSnapshot overview
► Insects memorize a visual template or “snapshot” of Insects memorize a visual template or “snapshot” of landmarks they experience at important locations of landmarks they experience at important locations of their environmenttheir environment
► The memory encodes the sizes and retinal locations The memory encodes the sizes and retinal locations of landmarksof landmarks
► Insects sequentially match this template to the Insects sequentially match this template to the environment upon return while maintaining environment upon return while maintaining consistent body alignmentconsistent body alignment
► Lateral scanning movement may aid the matching Lateral scanning movement may aid the matching process process
Testing the snapshot hypothesis Testing the snapshot hypothesis in a small scale arena in a small scale arena
environmentenvironment► Honey bee flight behavior during other visual Honey bee flight behavior during other visual
navigation experiments in our apparatus appeared navigation experiments in our apparatus appeared inconsistent with snapshot guidance.inconsistent with snapshot guidance.
► Investigated elements of snapshot navigation in a Investigated elements of snapshot navigation in a carefully controlled arena environmentcarefully controlled arena environment
Snapshot predictions of search behavior near the goal Snapshot predictions of search behavior near the goal location (tested by Cartwright & Collett, 1979, 1982; Cheng, location (tested by Cartwright & Collett, 1979, 1982; Cheng, 1999)1999)
Predictions of flights paths to the goal from distances of up to Predictions of flights paths to the goal from distances of up to two meters (largely untested)two meters (largely untested)
Consistent body axis orientation near the goal (Collett & Consistent body axis orientation near the goal (Collett & Baron, 1994)Baron, 1994)
Lateral scanning flights near the goal (Collett & Rees, 1997)Lateral scanning flights near the goal (Collett & Rees, 1997)