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236 Cards in this Set

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What happens if you give a nut to a squirrel?
Engages in burying behavior. You can raise squirrel without solids and he'll try to bury it even though he has never seen it. Shaped by inheritance
What is a stimuli that triggers a behavior?
Does a wasp learn to locate its nest by visual cues?
A wasp learns to use objects in its enviroment to locate its nest
What is the experiment that proves a wasp learns to use object in eviron to locate nest?
Placed cones around nest, then put cones not aroung nest, wasp heads for cones.
What is all necessary to elicit aggressive behavior in male European robins?
A tuft of red feathers.
What characteristics of the herring gull parent release pecking responses from their chicks?
A contrasting dot on a thin bill releases pecking responses. Head shape and color have little or no influence.
Maybe past event had long thin bill
How can we identify releasers?
Doing experiments
Stereotypic and species-specific behaviors are largely determined by what?
How do behavioral biologists believe that most behaviors have developed?
Through interaction of inheritence and learning?
Experiment. Is learning essence for song acquisition in white crowned sparrows?
White-crowned sparrorws that do not hear adult song as nestlings do not express the correct song when they mature. Therefore nestling birds learn a song template.
Do maturing white-crowned sparrows require auditory feedback to learn to express the correct song?
Even if the bird has the correct song template, he needs auditory feedback to learn to match it.
(do this by deafening a subadult bird that has heard the song of his father when a nestling.)
What are the benefits of inherited behavior?
Inherited behavior is highly ADAPTIVE for species such as, Those in which opportunities to learn are not available.
For species in which the risk of learning the wrong behavior is too high.
In situations in which msitakes are extremely costly (e.g. deadly, as when trying to escape a predator)
What are the three components of the cost of behavior
Energetic cost, Risk cost, Opportunity cost
What is energetic cost?
(Energy expended in performing the behavior) - (energy the animal would have expended had it rest)
What is risk cost?
The increased chance of being injured or killed as a result of performing the behavior, compared to resting.
What is opportunity cost?
Sum of the benefits the animal forfeits by not being able to perform other behaviors during the same time interval
Why are male Yarrow's spiny lizards only weakly territorial in the summer?
If lizards are territorial in the summer, they die at a higher rate than nonterritorial lizards.
Why is learning how to build a web for spiders inherited?
Young emerge after their parents have died
What are the two phases of learning a bird song?
Phase 1-Listens to others, phase 2- rehearsal. Needs both phases or song is wrong
What is culture?
A set of behaviors that are transmitted by learning across generations
What is an example of human behavior under genetic influence?
Around the world there are similar facial expressions (smiles). Displayed in populations that have had litte or no contact. Blind infants smile and frown.
Is culture unique to humans?
No, found in many animals.
What is the principle behind cost-benefit analysis?
An animal has only a limited amount of time and energy to devote to its activites. Natural selection is expected to favor behaviors with total benefits > total costs.
What should happen if a trait has benefits > costs?
Trait evolves.
When should behavior inheritance evolve?
When the "cost" of learning it is too high.
What can make the cost of learning terrriby high?
There is no one to learn from (spider's webs). Learning the wrong behavior has disatrous consequences (courtship with ducks). Mistakes are heavily sanctioned (rattlesnake and kangroo rat)
What is an example of why inherited behavior is favored if mistakes are heavily sanctioned?
With the kangroorat it inheritedly knows to try to escape a rattlesnake. It is inherited to flee because if it had to learn it it probably wouldn't escape and then would die.
What are examples of culture found in japanese macaques?
They have developed new methods of food preparation, methods were transmitted to other individuals in the population via IMITATIVE learning.
What are examples of culture found in chimpanzees?
Behaviors such as tool using to courtship differ between populations, such that each poulation has its own distinct behavioral culture
The characteristics of humans and other animals, behavior and otherwise lie in a WHAT?
What must be present in honeybee's for it to be hygenic?
Recessive uncapping and removal genes. (uurr)
Why is it benefitial for honeybees to be hygenic?
Bacterial infections can spread on dead larvae. Thus adaptive value for bees to remove dead larvae
What does U and R stand for in hygenic bee genetype?
U-Uncapping cell, R-Removal of larvae. uurr Hygenic bee. UuUr nonhygenic.
How do we know genes that determine behavior?
Tools of molecular genetics, Courtship behavior or male fruit files.
What does the fruitless gene do in the fruitfly
Causes 4 expressionof mating ritual, but the expression of this gene is cause by a cascade of genes, each dependent on sex.
What is a circadian rhythm?
Animal behaviors expressed in daily cycles. These control the daily cycle of behavior
Do circadian rhythms depend on the 24-hour cycle of light and dark?
No, this is seen because animals in constant darkness still demonstrare daily cycles of sleep, activity, eating, and drinking, they are said to have an internal clock.
What does the latin name for circadian come from?
From the latin words for "about" and "day"
Define rhythm.
A series of cycles and the length of one cycle is the PERIOD of the rhythm.
Define entrainment
Process of resetting the circadian rhythm by exposure to environmental cues.
What happens to animals in constant light or dark?
They experience a FREE RUNNING circadian clock. These animals will not be entrained to the 24-hour cycle of evironmennt.
How can circadian rhythms of free-running animals be entrained in lab?
Through short pulses of light or dark every 24 hours. Even this resets it.
What is jet lag?
The effect of flying across several time zones which takes your circadian rhythm out of phase with the environment.
Why does it take so long to recover from jet lag?
Takes at least n days to recover from n hour differences. Internal clock doesn't match environmental cues, phase shift 30minutes-1hr each day.
In mammals where is the master circadian clock located?
Suprachiasmatic nuclei (SCN). Two groups of cells found in the brain just above the area where the two optic nerves cross.
What is interesting about the eyes and SCN?
There is a physical closeness between the two
What happens to the destruction of SCN?
Loss of rhythmicity occurs.
What happens if a SCN is transplanted?
This can restore rhythmicity to the recipient of the period of which the individual that donated the issue was in.
Where is the location of the clock in invertebrates?
(mollusks) The cells driving circadian rhythms are in the eyes (evolved early in life)
Where is the location of the clock in protists and fungi?
Rhythmicity is a property of the individual cells.
What creatures is the SCN found in?
Only in vertebrates
What are the molecular mechanisms of the circadian clock?
Clock genes
What are the clock genes for fruit flies?
Per (short for period) and tim (short for timeless).
What happens to mutations in the per gene of the fruit fly?
Causes flies to have either short or long circadian periods?
What happens to mutations in the tim gene of the fruit fly?
Loss of circadian rhythms.
How are seasonal behaviors controlled?
Earth's revolution gives seasonal changes in environment, especially photoperiod.
What are circannual rhythms?
An annual rhythm usually shorter than 365 days, the neural mechanism are unknown
What is photoperiod?
Day length
What is a reliable indicator of upcoming seasonal changes?
What are photoperiodic animals?
Animals whose behavior or physiology is influenced by day length
How do bears or animals that hibernate know when it is time to wake up?
They cannot rely on day length as a cue of upcoming season change, so rely on circannual rhythms.
Define orientation.
When animals spatially organize their behavior.
What is the molecular basis of clock genes?
The per and tim genes when transcribed and translated act as the barrier itself preventing transcription. As it blocks its own productions there is a delay and this allows for the period of the cycle.
How do european starlings locate their winter quarters?
They use distance and direction navigation
What is piloting?
Simple means of navigation involving the use of landmarks
What animals use piloting as a means to orient themselves through landmarks?1
Gray whales use landmarks along the west coast of North America to find their way between the Bering Sea and the coastal lagoons of Mexico.
What is homing?
The ability of an animal to return to its nest site or burrow
What animal uses homing as a way to find nest?
Albatrosses return to the island on which they were raised after spending 8 or 9 years flying widely over southern oceans.
What is migration?
Seasonal movement between breeding and nonbreeding grounds
How do birds determine direction for flying?
Use sun and stars
How can animals use the sun as a compass?
They learn the time of day it is through their circadian clocks
What is migratory restlessness?
If birds are held in captivity they show increased amounts of oriented activity at about the time they would normally migrate.
What are methods of which homeing pigeons find their home?
Use the sun when available, their sense of the earth's MAGNETIC field when the sun is unavailable, and landmarks when close to home.
What is a time-compensated sun compass?
Shown in birds that are capable of using their circadian clocks to determine direction from the position of the sun.
What is communication?
It involves displays or signals that convey information to individuals, and the transmission of this information benefits the sender and the receiver.
What are the five channels of communication?
Chemical, visual, auditory, tactile, and electric.
What are pheromones?
Molecules used in chemical communication between individuals.
What are characteristics of sex attractants?
Tend to be small molecules that diffuse rapidly, such messages travel great distances and quickly disappear
How is the speed of diffusion of pheromone molecules determined?
Size and chemical nature of the molecules
Elaborate on pheromones released by sexually receptive female silkworm moths to attract males and scents released by mammals during the marking of territories.
Scent marks provide information such as species, individual identity, reproductive status, size, and when the animal was last in the area.
What are characteristics of scent marking pheromones?
Tend to be large molecules that create relatively localized, longlasting messages.
What information does the waggledance of the honeybee s
Dance speed describes distance (slower farther), Orientation towards hive is about direction.
What does the ordor on the honeybee dance identify?
Which flowrs to look for.
What are challenges of visual signals?
Person must be looking at right place & have no obstructions.
What animals use electric signals?
Some fishes
What communication channel is expected to evolve?
Natural selection favors channel where both sender and receiver benefit. Evolution of communcation systems are constrained by anatomical & physiological differences of species.
What is a benefit of auditory signals?
Communicate well over a distance.
What is the basic building block of the nervous system?
Nerve cells, Neurons
What is the most complex part of the human body?
The nervous system
Information is processed and transmitted by cells that form what?
The nervous system
Personality, ego, and emotions are all derived from what?
The nervous system
How does the nervous system communicate to cause behavioral or physiological response?
Through signals to EFFECTORS, such as msucles and glands
What do we call the brain?
The ganglia that is larger and more central than others
What is a ganglia?
A cluster of neurons
Do sea anemones, earthworms, squids have brains?
Yes, but fairly simple in some speciies. Sea anemone has a simple network of neurons that does little more than provide direct lines of communication from sensory cells to effectors.
Where are most of the cells of the nervous system found in vertebrates?
In the brain and spinal cord
The central nervous system (CNS) is made up of what?
The brain and spinal cord.
What is the simplest neural network
Consists of 3 cells. A sensory neuron connector to a motor neuron connected to a muscle cell.
What is the peripheral nervous system?
The PNS are neurons and supporting cells found outside the CNS
Is there any variation in brain structure among vertebrates
Structural similarities, but great differences in overall size and relative development o parts. Structure can do difference function in different vertebrates.
What is the relationship of the cerebrum relative to the rest of the brain for evolution?
Increases substantially from amphibians to reptiles to birds to mammals
What do humans and dolphins have in common (besides sex for pleasure)
Largest ratios of brain size to body size, and have the most highly developed cerebral cortext
What is the purpose of the cerebral cortex
Processes abstract information
Are there brain structures more conserverd than others?
Yes, the limbic system. Evolutionary primitive part of the forebrain. Evolved in emotions, instincts.
Is there a pattern in the evolution of brain structure?
Size of cerebrum relative to rest of brain increases substantially form amphibians to reptiles to birds and mammals.
What happened in the last several million years of human evolution in reference to the brain.
The most dramatic increase in the size of the cerebral cortex
What are electrical signals generated by the neuron's plasma membrane?
Nerve impulses (or ACTION POTENTIALS)
What are the four regions of most neurons?
A cell body, dendrites, an axon, and axon terminals
In the neuron, information is received through what?
In the neuron, information is transmitted through what?
What is a nerve?
A bundle of many axons carrying information to and from CNS
How do neurons process information?
From electric singals, impulses.
How is information transmitted through neurons?
Through the releases of chemicals called neutrotransmitters.
What is the synapse?
Junction between target cell and axon terminal
What is the purpose of the afferent portion of the peripheral nervous system?
Carries information TO the cns
What is the purpose of the efferent portion of the peripheral nervous system?
Carriest information FROM the CNS to the muscles and glands of the body.
Describe some parts of the afferent portion of the PNS
We are consciously aware of vision, hearing, pain, limp position. We are unaware of information such as blood pressure, deep body temp, blood oxygen supply
How can the efferent portion of the PNS be divided?
Into voluntary (conscious movements) and autonomic division (physiological functions)
How can the nervous system be engaged in so many tasts at the same time?
Subsystems function simultaneously
In addition to neural info, the CNS receives chemical information what?
From hormones circulating in the blood or neurotransmitters released by neurons.
The nervous system engages in many tasks at the same time, this is called what?
Parallel processing of information
Motor functions are from what part of the brain?
Frontal lobe
Visual functions are from what part of the brain?
Occipital lobe (back)
Auditory functions are from what part of the brain?
Temporal lobe
How can we know what each part of the brain does?
From accidental damage and resulting lost abilities. Experiments-to measure neuron activity in area of interest in response to various stimuli
Facial recognition is a function of what lobe?
Temporal lobe. Evidenced by research with monkeys. Measured neurons in response to faces
What happens to damage to the right parietal lobe?
Causes condition called contralateral neglect syndrome. If patient is asked to copy a drawing, left side of copying is neglected
What is non REM sleep?
Slow wave, divided into four stages
What is REM sleep
Rapid eye movement
How does one know that sleeping and dreaming involve electrical patterns in the cerebrum?
Recording brain and muscle electrical activity
What happens to our muscles in REM sleep and why?
Skeletal muscles completely paralysed, maybe to prevent acting out dreams.
How long does short term memory last?
10 to 15 minutes if not reinforced and transferred to long term memory
What information does the round dance of the honeybee express?
Distance the food is from hive, If food is within 100m, but not direction. Ordor says what flower to look for.
What are benefits of visual signals?
Rapid and versatile, but limited by directionality.
How is human non-REM sleep divided?
Into 4 stages of increasing depth
What happens during REM sleep?
Dreams and nightmares. The brain also inhibits both aferent (sensory) and efferent (motor) pathways.
What happens to a person who lacks hippocampus on both sides of the brain?
They are unable to create new long-term memories, Although long-term memories before the surgery are intact.
How have knowledge about the neural mechanisms for the transfer of short-term memory to long-term memory have came from?
Observations of people who have lost parts of the LIMBIC system, most notably the hippocampus
What is memory?
The ability of the nervous system to retain what is learned and what is experienced
What are sensory cells?
Cells that transduce physical or chemical stimuli into signals that are transmittable and interpretable
What are mechanoreceptors?
Receptors that are sensitive to mechanical forces, they are responsible for the perception of touch, pressure, and tickle.
What is the purpose of stretch recptors?
To inform the body about the location and load of body parts. They are in muscles, tendons, ligaments
What determines sensitivity?
Density of mechanorecptors
How do we detect mechanic stimuli?
What are phantom limbs and why are they felt?
The feeling of limbs after they have been removed. They are felt because the CNS neurons are still in place.
Do we sense all information that we receive?
No, many information is sense without us being conscious of it. Levels of CO2, blood sugar, oxygen
What are chemorecptors and what do they do?
They detect chemcial signals, and are responsible for smell and taste, and monitoring internal environmental factors such as CO2, O2 in blood.
Explain on how male silkworm is attracted to chemical signals of females
Receptors on each antenna has about 10,000 bombykol senstive hairs. A single molecule can stimulate a perceivable action potential. When 200 hairs are activited males flies upwind towards concentration gradient.
How many hairs are needed to be activitated for male silkworm to fly towards concentration gradient of bombykol pheromone?
200 hairs or more.
What is the sense of taste called?
What cause the sensation of taste?
Sensory cells called taste buds, they are NOT neurons.
Interpretation of action potentials as sensations depend on what?
Which neurons in CNS receive them.
How many taste buds are embedded in the epithelium of the tongue?
How often are taste buds replaced? Why don't we lose sense of taste?
Every few days. Associated neurons live on
How do snakes smell their prey?
Smell by flicking their tongue to capture molecules and then fitting the tongue into cavities in the roof of the mouth where there are concentrations of olfactory receptors.
What are ranges of photosensitivity?
From ability to orient to the sun to the ability to see
What are photoreceptor cells?
Cells that detect electromagnetic radiation of a particular range of wavelength
What are molecules used for photosensitivity called. What what is interesting about these?
Called Rhodopsins which capture photons of light. These have been conserved throughout evolution
How does vision result from?
Results from when eyes focus patterns of light onto layers of photoreceptors.
Are there just one type of eyes?
No, there are eye cups, compound eyes, lensed eyes.
What are the eye structures of flatworms
Eye cups that obtain directional information
What are the eyes of arthropods and what do they do?
They have compound eyes that detect shapes and patterns. OPtical units are called OMMATIDIA
What similarities do vertebrates and cephalopod mollusks have in common about eyes?
Through they evolved through different means, they both have LENSED eyes that allow focusing.
What is the eye structure that allows light to passage through.
A transparent CORNEA
What is the iris and what does it do?
Pigmented section inside the cornea that controls the amount of light that can enter.
What is the region where light enters in the eye?
The pupil
What is the purpose of the lenses in eyes?
Allows the eyes to focus light.
Why do old people need glasses when old?
Lenses become less elastic with age. Causing the need for reading glasses
What is the area of the retina has the densest concentration of photoreceptors?
The fovea
Why from an engineer's point of view the eye is less than perfect?
Light must pass through all the layers of cells before photons are captured by rhodopsin. There is a blind spot in human
Are eyes too perfect to evolve by natural selection?
Eyes have evolved repeatedly in different animals. Computer simulations show that the time needed for evolution by natural selection to produce image-forming eyes is in the order of half a million years. Eyes far less than perfect.
Are there senses that animals have that humans don't?
Yes. UV and Infrared. Fruit fly has some photorecptors sensitive to uv light. Some flowers have patterns humans can't see. PIt vipers can locate infrared radition in total darkness.
What are the two types of major kinds of vertebrate photorecptors?
Cones and rods
Elaborate on rods in the eye
More sensitive to light than cones
Elaborate on cones in eyes
These are responsive to different wavelengths of light for color vision. Humans have 3 kinds, 1 best for red, 1 best for blue, 1 best for green.
What are autotrophs?
Use an abiotic source of energy to synthesize all of their components.
What make up most of autotrophs?
Most plants, some bacteria & protists
What are heterotrophs?
These must obtain nutrition by eating other organsims
What are heterotrophs that consume dead organsims?
Detritivores (earthworms, crabs. Also consume waste of other organisms. Decomposers (protists, fungi), Scavengers (vultures, hyeneas)
What are heterotrophs that feed on living organisms?
Why do animals need to eat?
Organisms need energy
What are the components of food that provide energy?
Fats, carbohydrates, and proteins
What is a humans basal metabolic rate?
Metabolic rate resulting from all of the essential physiological functions that take place in a resting state.
What is the basal rate for an adult female? Male?
Female 1,3000-1,500 kcal/day. Males 1,600-1,800 kcal/day
What is a calorie?
The amount of heat necessary to raise the temperature of 1 g of water 1degree celsius (1 kcal=1000 cals)
How are carbohydrates stored in the body?
Stored as glycogen
What is the most important form of stored energy?
What happens if an animal has insufficient caloric intake?
Undernourished animal
Where do heterotrophs ultimately dervice their energy and structural bluding blocks?
At the source it is from autotrophs
What must an undernourished animal must do to provide energy they need?
They must metabolize molecules of their own body. First are glycogen and fat, and last is protein.
What are cetrain basic organic molecules that animals need and cannot synthesize themselves?
Carbon skeleton (an example are amino acids)
What are essential amino acids?
Amino acids that animals cannot synthesize themselves.
Does food brings us only energy?
No, it also provides essential nutrients such as amino acids, minerals and vitamins
What do mineral elements assist with?
Ca provides Bone growth & maintence, blood clotting, nerve & muscle action, enzymatic reactions
What are vitamins?
Carbon compounds that animals require for normal growth and metabolism, but cannot synthesize themselves.
What do vitamins C & E do?
Involved in protection against oxydation of celluar components
Malnutrition results from what?
Lacking an essential nutrient
A chronic shortage of any nutrient produces what?
A deficiency disease
How can deficiency diseases occur?
Shortage of nutrient, also from inability to absorb or process an essential nutrient even if it is present in diet
Though humans can synthesize almost all required lipids from food, what must be obtained from a dietary source?
Essential fatty acids
Why can fat-free diets be dangerous?
Fail to provide essential fatty acids (w/ harzardous consequences and damage to nervous system)
What happens with excess of water-soluble vitamins?
Excreted in the urine
What happens with excess fat-soluble vitaminis?
They can accumulate in body fat and build up to toxic levels in the liver.
What are some fat soluble vitamins?
HOw does our body regulate food intake?
Conscious sensations of hunger and satiety
What is the region of the brain that influences hunger and satiety?
Region called hypothalamus
What happens when a particular region of the hypothalamus in rats is damaged?
Rats will increase food intake and become obese
What happens if a different region of the hypothalamus is damaged in rats?
Rats will decrease their food intake and become skinny?
What feedback information helps regulate body weight?
Levels of blood glucose and insulin, as well as signals from fat metabolism, influence satiety and hun
What happens when a mutation in gene that codes for the protein leptin occurs in mice?
They eat enormous amounts of food and become obese?
What happens if leptin is injected in mice with mutated leptin protein genes?
Ate less and lost body fat
Where are leptin receptors present in the brain?
In regions of the hypothalamus that are involved in control of hunger and satiety
What levels of leptin do obese humans have?
HIGHER than normal circulating levels of leptin
Could a deficit in leptin production be responsible for obesity in humans?
Apparently not, obsesity associated w/ higher than normal levels of leptin.
Why are predators agents of natural selection and mortality?
They have a selection on prey phenotypes because they do not capture prey individuals rnadomly
HOw are prey agents of natural selection?
Because predators may be more or less successful at getting their nutriments out of them.
What adaptions do prey and predators generally have?
Predators-To be more efficient consumes. Prey-make them more difficult to be predated upon.
What is an organism's habitat?
Environment where an organism normally lives
What is an organism's home range?
AREA where organism lives
Explain the way a red abalone chooses its habitat.
Begins life as MOTILE LARVA for seven days (dispersal stage). Then is guided by chemical signals from CORALLINE ALGAE (main food source), settles on seafloor and metamorphoses into adult.
What happens in a lab to a red abalone when scientists place chemical singal whereever they want?
They settle down where ever signal is palced. This chemical is only produced in nature by coralline algae
What is optimality modeling?
Constructing hyptohesis on how a forgaing animal SHOULD BEHAVE, first specifing the OBJECTIVE of the behavior, the CONSTRAINS on possible choices, and attempts to determine the behavioral choices to best achieve objective
Do foraging bluegills select prey to maximize their rate of energy intake?
Bluegills select prey to maximize thier rate of energy intake. But NOT selective is prey is not a lot
What is the foraging theory?
A theory that tries to answer questions related to how an animal looks for and acquires food.
Why do the shape of teeth & jaws differ among vertebrates?
Behavioral and anatomical adoptions reflect feeding types.
Why do giraffes have a long neck?
Used as a weapon in mating ritual, the longer the heavier
What is a characteristic of dominant giraffes in their societies?
Males w/ thickest necks are the dominant ones.
What are some adaptations for prey against predators?
Toxic hairs, tough spines, noxious chemicals
Among plants what type of defense is widespread?
Chemical defenses
What are secondary compound defenses in plants?
Chemicals contained in plants that aid their defense from herbivores
What are the two types of defensive secondary compounds?
Acute toxins, digestibility reducing compounds
What is the most popular of digestibility reducing compounds?
Tannins. These bind proteins in the leaf and digestive enzymes of the herbivore, reducing the ability of the herbivore to extract proteins from the leaves
What happens when a caterpillar chews on a tomato leaf?
The damage triggers a defense. Singaling process includes two hormones. Systemin and jasmonates. The jamonates act to attract insects that prey on caterpillars. A protease inhibitor is produced that interfers with insect's ability to digest food.
Why don't plants poison themselves?
Either compartmentalize their toxins, or use modified enzymes or receptors that are unaffected by the chemical.
What is mimicry?
Defense mechanism in which an animal evolves to resemble an inedible or unpalatable item or organism
When does cooperation establish among interacting individuals?
When performing the behavior is costly to the individual, but the cost is offset by the benefit obtained from the interaction.