Tetrachromatic color vision modeling (Trochilidae)

Knowledge graph centered on Tetrachromatic color vision modeling (Trochilidae) with 35 nodes and 119 connections. Top connected: Hummingbird, Ipomopsis, Selasphorus platycercus, Colias, Mimulus.

Method synopsis

Novel method using programmable LED devices to test color discrimination in free-flying hummingbirds through reward-based choice experiments. Birds choose between tubes displaying different colors in avian tetrachromatic color space, with sucrose rewards for correct choices.

Synthesized from method descriptions across 2 papers using this protocol.

Procedure as described in the canonical source

Steps below were extracted from the paper that introduces this protocol — Wild hummingbirds discriminate nonspectral colors (2020), Proceedings of the National Academy of Sciences. Implementations in other papers (listed below) may differ.

1. Establish experimental arena
   Set up experimental arena in a small wooden building at RMBL site. Mount two tripod platforms 1 meter apart and 1.4 meters above ground. Place TetraColorTube devices on tripods so projected light cones overlap before reaching a highly diffusing display surface.
   Quantities: Two tripod platforms, 1 meter separation, 1.4 meter height above groundDuration: Setup prior to each experimental sessionConditions: Conducted during hummingbird breeding season (June-August), natural outdoor lighting conditions
   Equipment: tripod platforms, TetraColorTubes, diffusing display surface
2. Calibrate color stimuli
   Calibrate TetraColorTube LED outputs using Ocean Optics USB4000 spectrometer with CC-3-UV-S cosine corrector. Measure spectral outputs and convert to hummingbird cone stimulation values using predicted hummingbird cone sensitivities and oil droplet models.
   Quantities: Four LED channels per tube (UV, blue, green, red), spectral measurements across 300-700nm wavelength rangeDuration: Calibration performed before experimentsConditions: Controlled lighting conditions for accurate spectral measurements
   Equipment: Ocean Optics USB4000 spectrometer, CC-3-UV-S cosine corrector, TetraColorTubes
3. Train hummingbirds for color discrimination
   Present two TetraColorTubes to visiting hummingbirds - one reward tube containing ~35% w/w sucrose solution, one nonreward tube containing water. Train birds to associate specific colors with reward. Swap positions of tubes between trials to prevent spatial learning.

Typical Equipment

• TetraColorTubes
• tripod platforms
• sucrose solution
• Ocean Optics USB4000 spectrometer

Output Measurements

• color discrimination probability
• choice frequency
• learning curves

Papers Using This Protocol (3)

Species Studied With This Protocol