Flashcards in Lecture 16 Deck (61)
Are dogs color blind?
Dogs have the ability to detect
color in a limited scope
compared to humans. They can see more than black/white.
What study did Kasparson do with dogs?
Researchers trained dogs to associate dark yellow paper with food reward
The dogs were tested with either a dark blue box or a light yellow box
Dogs reliably selected the color matched box in ______ of test trials
Visual systems have evolved to detect light. How?
Light sensitive organs have developed at least three separate
times in convergent evolution (for ‘camera’ eyes) This process triggers an electrical response in the receptor neuron
Vision provides a means of detecting objects in an animal’s
surroundings. What are these?
Luminance (intensity differences; brightness) – Reflectance (spectral composition; color)
Vertebrate visual systems contain two types of receptors:
Rods: low light conditions
Cones: light sensitive photoreceptors to perceive color.
Properties of color?
■ Chroma (degree of saturation
or purity of the dominant
■ Cone cells in the retina contain a pigment called ______
group of light-sensitive proteins found in photoreceptor cells of the retina
Opsin absorbs light energy which...?
activates retinal neurons and results
in action potentials in the optic nerve
Two different wavelengths of light
can produce the same ______ ____ _______ in a cone cell
pattern of activation
Outputs of ____ _____ are combined
and compared in the visual
Tetrachromatic color vision
based on four types of cone cells – Birds, lizards, turtles, and many fish
Trichromatic color vision
based on three types of cone cells – Old world primates, humans
Dichromatic color vision
– based on two types of cone cells – Most other mammals (dogs, cats, etc.)
Progenitors of mammals lost ____ of the four types of cones during a
period in evolutionary history when they were primarily _______.
Human color vision depends on interactions of three types of cones:
red, green, blue
Most other mammals are ________
Dichromacy occurs in humans when one of the cone pigments is missing. What are the types?
Protanopia: no red receptor
Deutanopia: no green receptor
Tritanopia: no blue receptor
Several groups of
reptiles, fish) have
_______ distinct types of cones
Bees are technically __________
Appears to be a trade in
sensitivity between _____ and
Bees lack sensitivity to what?
red end of the electromagnetic spectrum
What are the properties of light used in animal communication?
What are spatial characteristics?
Variations in shape, size, surface features and color pattern.
What are temporal characteristics?
changes in pattern of color, surface, color change and apparent size/shape over time.
_______ ________ is very common for increasing visibility.
Forests have 4 major light habitats...?
Forest Shade: Yellow-green
– Woodland Shade: Blue-gray
– Small Gaps: Reddish
– Large Gaps: “White
Due to natural differences in these light spectra an animal my appear...?
very different in each light environment