Exam 2 Flashcards
White-crowned Sparrow Example
Shows nature-nurture interactions and innate predispositions
Regional dialects: environmental (learned) behavior—The song one hears is the song one sings
Chicks raised in isolation show similar genetic tendencies (no rapid changes in frequency) but must be exposed to external sound to make a successful mating song
Four different sparrows are raised in environment with songs of different species: All of them learned songs closest to the one of their own species—innate predisposition
When their own species song was not available, they learned from the tutor songs but constructed songs by combining them
Innate predisposition
Genetic disposition for a certain behavior
Sensory Period
Learning period for songbirds
Sensorimotor Period
Starts vocalizing, practices to improve. Listening to their own vocalized song is essential to achieving replication of the earlier song (sensori + motor).
If the researcher cuts the auditory nerve then song crystallization never happens
Open-ended Learning
Individuals can acquire new song elements throughout life
Closed-ended Learning
Must listen to a tutor song during a specific period. Once crystallization has occurred further learning is no longer possible
Why is songbird behavior studied so often?
The pathways and interactions in the brain are well-known
Lyre Bird Example
Open-ended learning. Mimics sounds or birds and man-made objects. Can mimic camera shutter sounds, chainsaws, car alarms
Great Tit Personality Example
They have genetically heritable ‘adventurous’ personality trait. It can be seen on a parent-offspring regression chart, where the slope is the degree of inheritance.
Yellow Fruit Fly Example
Shows an example of pleiotropy.
Yellow flies are rare in nature but common in laboratories. They measured yellow mutants behavior and reproductive success: Wild type males have a higher mating success rate than yellow mutants.
Pleiotropy: single gene affects 2+ traits
The gene that affects color also affects mating behavior.
Ant Basic Characteristics
There are diverse caste structures among the different species. All ants are eusocial.
One or several queens per colony.
10^2 to 10^7 worker individuals per colony.
Drones are fertile males, much fewer in number than workers.
Soldiers and workers are females, but do not produce eggs.
Higher group selection—mutant genes in individuals do not get passed along when individuals do not reproduce.
Army ants: do not have a nest, workers cooperate to attack prey much larger than themselves
Fire Ant Example
Monogyne and polygyne types (1 queen or multiple queens)
Scent is what differentiates colonies, they use scent as a cue to know what individuals are enemies
Gp-9^BB is the monogyne gene
Gp-9^Bb is the polygyne gene
Gp-9^bb ants aren’t viable
Polygyne colonies can’t smell a difference between other colonies very well:
- Colonies sometimes merge
- Reduced aggression between colonies
- More advantageous in locations where there is enough space to expand
Major vs. Minor Genes
Major: individual gene is responsible for large amount of phenotypic variation
Minor: individual gene contributes a small amount of variation (additive)
Mice Risky Behavior Example
The experiment shows how genes influence behavior.
Arginine vasopressin (AVP) is a peptide hormone that affects stress behavior
AVPR1A receptor gene in mice
Conducted stress tests on wild-type and V1aR gene knockout mice
Elevated maze test, open field test, light/dark box
The knockout mice were more willing to go into riskier areas
What determines phenotype?
Genetics, environment, and gene-environment interactions
What determines gene expression?
Environment, time, type of tissue/cell/etc
Fish Aggression Example
Experiment shows phenotypic variation caused by environment.
Some are raised in oxygen rich environment, some are raised in oxygen poor environment.
They are more aggressive when in the environment they grew up in (because they will expend more energy in a familiar environment)
Fruit Fly Aggression Example
This example shows that gene expression is influenced by environmental factors.
Treatments: court a female, interact with a rival male, no interaction (control)
Analyzed mRNA to see which genes were expressed during each treatment
16 genes associated only with male-female courtship behavior
Hundreds of genes associated with male-male interactions
Reaction Norm
Function showing the relation between environment and phenotype; range of behaviors expressed by a single genotype over a range of environments. If the reaction norms of two genotypes cross, then there is GxE interaction
Rover and Sitter Fruit Flies Example
Rovers go out for food, sitters wait for food to come close by
Typically, rovers will travel farther in order to find other food. However, when food is scarce, rovers behave like sitters and will not leave a food patch to find a new food patch.
This shows GxE interactions; the two genotypes have different reaction norms.
Fields of study
Genomics (genes), transcriptomics (mRNA), proteomics (proteins), metabolomics (substrates, intermediates, and products of cell metabolism)
Sensory Systems
Visual, mechanosensory (movement: auditory, vestibular, lateral line), somatosensory (pain, touch, itch, thermal), chemosensory (olfactory, gustatory (detection of dissolved chemicals often within the mouth)), electrosensory, magnetosensory
Chemosensory senses
Gustatory are the 5 taste elements. Olfactory (smell) is much more complex
Mice Gustatory Example
T1R1, T1R2 and T1R3 receptor knockouts. Knockouts 1 & 3 had no response to tasting amino acids (umami) and knockouts 2 & 3 had no response to tasting sugars.
Cuttlefish Olfactory Example
Sneaker males (pretend to be females)
They aggregate based on odor and can smell new eggs
Butterfly Sexual Dimorphism Example
Males and females appear different under UV light
UV Sexual Selection in Birds Example
Females prefer males with light heads/more reflectance
Tested this by applying sunscreen to male birds’ heads
Animals with tetrachromacy
Most reptiles, birds, amphibians, fish, insects
Animals with trichromacy
Most primates, honeybees
Animals with dichromacy
Most mammals, colorblind humans
Animals with monochromacy
Seals, dolphins, whales, night monkeys
Pit Organ Example
A hole on the face to detect infrared light
Cavity filled with air, like the retina there is a very thin membrane at the back, it is lined with heat sensors
It acts like a pinhole camera
Infrared light = longer wavelengths
When placed in a room with warm and cool balloon, they attack the warm balloon
Elephant Communication Example
Communication using infrasound. Infrasound diminishes slowly so it can travel farther through the environment. Can detect it through the ground
Ultrasonic sound
Small animals can hear and sometimes communicate in ultrasound
Lateral Line System
Detects water movement
Sensors are embedded in the skin, hairs detect motion
Antlion Example
Shows how researchers can learn if an animal can detect prey using vibrations.
They build sand cones, the ants go in and antlion larvae attach with their pincers. They can capture the ants by throwing sand in the direction of the vibration so as to create an avalanche
Barn Owl Example
Key stimulus: noise, fixed action pattern: head turning
Model mouse is pulled with a string, creating a very quiet scratching noise. The barn owl orients its head towards the noise source, then flies towards the target.
Can detect differences of 10 microseconds
The two neurons receive the signal, and transmit it along the huge axon to both sides of the brain. The neural axons enter the side of the brain that is on the same side from the top, and enter the opposite side from the bottom. This causes the axons to overlap and translate interaural time differences.
Coincidence: the signals arrive at the same time to the neuron
Two purposes of the senses
Identification and localization
Vision has a great advantage with localization because it is intrinsic to how the retina works
When you listen with one ear, you are unable to localize the sound
Which animals have electroreceptors?
Many fish, amphibians, insects, and a few mammals
Electric Fish Example
They produce weak electricity for navigation and communication
Can sing songs using electricity
During spawning they make a specific pulse; the females carry the eggs in their mouths and then put them into the spawning hole once the male communicates via chirping
Ampullae of lorenzini
Organ in sharks and rays for electric detection
Bumblebee Electrical Receptor Example
Flowers have a static charge that bees can sense using their hairs
Magnetic Termite Example
Heat is an enormous problem for large termite mounds
They always build the broadest part of the mound in the direction of least sun radiation (east-west)
Bat and Mantis Example
Example of sensory coevolution
Bats use ultrasonic calls, frequency of the call increases as it gets closer to its prey
Tympanal membrane: Single eardrum in insects, detects bat calls
Mantises are able to escape attacks
Deaf mantises have a lower escape rate
Honeybee Communication
Bees have an internal clock that doesn’t require stimulus: 1 hour time difference = 15 degree movement of the sun’s position
Waggle Dance
Waggle duration
Long duration: distant
Short duration: near
Circular dance: very close
Amplitude of waggling: quality of food source
Compound eyes: sensitivity to polarized light
Their head acts as a gravitation sensor: Head tilt angle is sensed by sensory hairs around the neck
Bee ancestral species made horizontal hives, dance is directly pointing at the food source
Vervet Monkey Example
Example of auditory alarm calls
Different alarm signals depending on the predator: Land, aerial, and snake
This is because different responses are needed based on the predator—go into the tree if there is a land predator, hide in the bushes if there is an aerial predator, stand on hind legs to intimidate snakes
What are the two pieces of information that an alarm call may contain?
Information or Influence
Information: there is a leopard, there is a snake
Influence: Climb a tree, look down
We don’t know if the call contains information or influence
Titmouse Communication Example
Call seems to contain information
Number of D-note signals conveys the risk of the predator
Small high-risk predators vs. Large low-risk predators
They gather together and make lots of loud noise (mobbing behavior) during high-risk attacks too
Ant Pheromone Communication Example
Shows that the environment influences signaling
Doesn’t work well in hot environments because the pheromone evaporates
Red stick is without pheromone
When the original stick is heat-treated, the ants do not prefer one over the other
May explain why social foraging ants do not forage at high temperatures
Fish Visual Signal Example
Shows that the environment influences signaling
Male fish morphs are either blue or yellow
Blue males contrasted most with
background in the beach habitat
Yellow males contrasted most in the root
habitat
Higher mating success in environment with more contrast
Accurate Signaling
Advantageous to both signalers and receivers, similar fitness interests
As opposed to inaccurate, where the receiver is at a disadvantage
Conditions that favor accurate signaling:
Fitness interests of signaler and receiver are similar
Signals cannot be faked
Signals will be accurate indicators when they are costly to produce or maintain
3 Accurate Signaling Examples
Horned beetle: Only males have horns, shows his strength
Pheasant: wattle coloration for mate attraction
Stalk-eyed fly: grows stalk to make eyes are far apart as possible, courting signal
Aposematic Coloration
Warning coloration signaling associated with chemicals or toxins. Bright coloring is costly.
Betta Fish Signaling Example
Example of accurate signaling
Can open and fold their gill cover to make themselves appear larger during fights
When oxygen is not available, the betta fish doesn’t open his gill cover because it is too costly
