Lecture 16

Question 1

Are dogs color blind?

Answer 1

Dogs have the ability to detect
color in a limited scope
compared to humans. They can see more than black/white.

Question 2

What study did Kasparson do with dogs?

Answer 2

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

Question 3

Dogs reliably selected the color matched box in ______ of test trials

Answer 3

70%

Question 4

Visual systems have evolved to detect light. How?

Answer 4

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

Question 5

Vision provides a means of detecting objects in an animal’s

surroundings. What are these?

Answer 5

Luminance (intensity differences; brightness) – Reflectance (spectral composition; color)

Question 6

Vertebrate visual systems contain two types of receptors:

Answer 6

Rods: low light conditions
Cones: light sensitive photoreceptors to perceive color.

Question 7

Properties of color?

Answer 7

Brightness (intensity) 
■ Hue
■ Chroma (degree of saturation
or purity of the dominant
frequency)

Question 8

■ Cone cells in the retina contain a pigment called ______

Answer 8

opsin

Question 9

Opsin

Answer 9

group of light-sensitive proteins found in photoreceptor cells of the retina

Question 10

Opsin absorbs light energy which…?

Answer 10

activates retinal neurons and results

in action potentials in the optic nerve

Question 11

Two different wavelengths of light

can produce the same ______ ____ _______ in a cone cell

Answer 11

pattern of activation

Question 12

Outputs of ____ _____ are combined
and compared in the visual
nervous system

Answer 12

cone cells

Question 13

Tetrachromatic color vision

Answer 13

based on four types of cone cells – Birds, lizards, turtles, and many fish

Question 14

Trichromatic color vision

Answer 14

based on three types of cone cells – Old world primates, humans

Question 15

Dichromatic color vision

Answer 15

– based on two types of cone cells – Most other mammals (dogs, cats, etc.)

Question 16

Progenitors of mammals lost ____ of the four types of cones during a
period in evolutionary history when they were primarily _______.

Answer 16

two, nocturnal

Question 17

Human color vision depends on interactions of three types of cones:

Answer 17

red, green, blue

Question 18

Most other mammals are ________

Answer 18

dichromats

Question 19

Dichromacy occurs in humans when one of the cone pigments is missing. What are the types?

Answer 19

Protanopia: no red receptor
Deutanopia: no green receptor
Tritanopia: no blue receptor

Question 20

Several groups of
animals (birds,
reptiles, fish) have
_______ distinct types of cones

Answer 20

four

Question 21

Bees are technically __________

Answer 21

trichromatic

Question 22

Appears to be a trade in
sensitivity between _____ and
________ wavelengths

Answer 22

red, ultraviolet

Question 23

Bees lack sensitivity to what?

Answer 23

red end of the electromagnetic spectrum

Question 24

What are the properties of light used in animal communication?

Answer 24

Spatial characteristics

Temporal characteristics

Question 25

What are spatial characteristics?

Answer 25

Variations in shape, size, surface features and color pattern.

Question 26

What are temporal characteristics?

Answer 26

changes in pattern of color, surface, color change and apparent size/shape over time.

Question 27

_______ ________ is very common for increasing visibility.

Answer 27

Brightness contrast

Question 28

Forests have 4 major light habitats...?

Answer 28

Forest Shade: Yellow-green – Woodland Shade: Blue-gray – Small Gaps: Reddish – Large Gaps: “White

Question 29

Due to natural differences in these light spectra an animal my appear...?

Answer 29

very different in each light environment

Question 30

What are some factors influencing the evolution of signals?

Answer 30

Properties of the physical environment where the signal is generated – Perceptual systems of individuals (potential mates, predators, prey) receiving the signal – The nature of the information signaled

Question 31

What are the characteristics of warblers?

Answer 31

``` 8 species, all small and green No color patches – Two wing-bars Two wing-bars plus a crown-stripe – All of the above plus white outer tail feathers ```

Question 32

The distribution of patches across species is nested...?

Answer 32

Species with more complex patterns contain all patches of | simpler patterns

Question 33

Species can be ranked from _____ to _______

Answer 33

duller, brighter

Question 34

The ability to perceive visual signals is linked to what?

Answer 34

ambient light in the environment ( should have a direct impact on the evolution of coloring and behavior signals)

Question 35

Warblers that breed in the dark, dense habitats have what?

Answer 35

have a | greater number of color patches than those that breed in lighter, open habitats

Question 36

Strong negative correlation between...?

Answer 36

between wing-bars (brightness) and light | levels in the natural habitat

Question 37

Habitats of warblers?

Answer 37

Bright species have the most stripes; may serve as camouflage to predators – If color patterns are used for intraspecies communication and the visibility of these patterns depends on the background, then species in dark habitats should have the brightest coloring

Question 38

Variation in display is associated with location of color patches. What are some of those locations?

Answer 38

Species with crown-strips bow their heads in display – Species with rump patches turn and flash their rumps

Question 39

Display movements enhance visibility of the patches. What is an example?

Answer 39

Temporary effect due to specific movements

Question 40

Since different species use different display patterns for intraspecies, how is communication linked?

Answer 40

the effects may be linked primarily to the differing | displays

Question 41

What should provide evidence of the effect of | coloring

Answer 41

Altering the level of conspicuousness during display by eliminating or enlarging color patches should provide evidence of the effect of coloring

Question 42

Males of the species inornatus were manipulated in 1 of 3 ways?

Answer 42

Control group: … – Reduced: wing-bars were painted with green paint – Enlarged: wing-bars were painted with yellow paint

Question 43

Signals were manipulated while males were establishing territories and ______ to females arriving at the breeding grounds

Answer 43

prior

Question 44

Males from the control group had ___________ sized territories

Answer 44

intermerdiate

Question 45

Males in the reduced group had the __________ territories

Answer 45

smallest

Question 46

Territory shifts were immediate with the ______ ________ male taking over portions of the less conspicuous males

Answer 46

more conspicuous

Question 47

Songs aren't used in territorial displays suggesting what?

Answer 47

conspicuousness is a primary form of communication between individuals Increased territory size was correlated with increased levels of conspicuousness

Question 48

Some minimal level of ___________ is necessary to maintain a | territory and reproduce

Answer 48

conspicuousness

Question 49

What is sensory drive?

Answer 49

Conspicuousness is context-dependent thus the properties of the environment will bias the direction in which signaling characters evolve

Question 50

Color patterns, habitat choice, and courtship/display patterns appear

Answer 50

evolve together

Question 51

Properties of the environment can lead to what?

Answer 51

species divergence | whether or not perceptual systems vary

Question 52

Properties of the environment appear to influence what?

Answer 52

the evolution of | conspicuous coloring

Question 53

Coloring can vary across what?

Answer 53

body structures to take | advantage of the different levels of illumination

Question 54

What is reverse countershading?

Answer 54

A form of conspicuous coloring that serves | to increase visibility of the animal that is illuminated from above

Question 55

What is countershading?

Answer 55

protective coloration of some animals in which parts normally in shadow are light and those exposed to the sky are dark.

Question 56

If ambient light is strongly colored, animals can use...?

Answer 56

Contrasting color patches – Color patch that matches the ambient light peak and surround it with colors that reflect poorly

Question 57

Define disruptive coloration?

Answer 57

uses patterning to interfere with the perception of the true outline of the animal – … – Disrupt a receiver’s eye from the animal’s outline (like zebras)

Question 58

Define movement contrast?

Answer 58

terrestrial and shallow water environments present a moving background – Wind, wave action

Question 59

Animals attempting to stand out against this type of background use _______, ________ accelerating movement

Answer 59

jerky, rapidly

Question 60

_________ and striped color patterns often work together in creating crypticity or conspicuousness

Answer 60

Movement

Question 61

Stripes ___________ to the direction of motion conceal motion.

Answer 61

parallel