BIO111 Exam #4 (Final but not Cumulative portion)

UR-Minckley

neuronal action potential

the propagation of change in the resting membrane potential of a neuron to send electrical signals through the axons to other neurons, muscles, or glands

how are all senses perceived?

by chemical signals

how is the brain compartamentalized?

divided by senses (i.e. visual cortex, auditory cortex, etc.)

parietal eye

an eye on the top of some vertebrates heads (i.e. frogs) that processes information on light (daylight or night time) —> determines behavior and activity

pineal gland

the only unpaired gland- central location in brain allowing to act as a central timekeeper by processing light-dark cycle info from retina- unified and non-redundant regulator (“biological clock”)

what is unique about human eyes?

• the only primate with a white sclera

identify the parts of a vertebrate eye

why is there a blind spot between 0 and 20 degrees in vertebrate vision?

• the optic nerve creates a blind spot in vision where all the “cords” of the rods and cones are routed toward the brain to be processed

rods vs. cones

rods- sensitive to low light

• bad design because rods blocked by other cells

cones- detect color and sharp detail in bright light

• densely packed in the macula- at 0 degrees

color sensitivity

red cones + blue cones

• green wavelength spectrum is seen by both red and blue cones

structure of retina

• rods and cones

• information processing cells (horizontal cells and amacrine cells)- compare information across cells but no action potentials sent

• ganglion cells- only cell that generates an action potential- synapse with multiple ganglion cells that connect to optic nerve

• optic nerve- million axons

distribution of photopigments

• mostly red, few blues

• insensitive to short wavelengths (i.e. cyan to deep blue)

• highly sensitivity to long wavelengths (i.e. yellow and orange)

• no blue cones in center of retina- high acuity

  • explains the disappearance of small blue objects when you fixate on blue objects

trichromatic theory, evidence, and counterargument

• theory of color vision that there are 3 different types of cones (red, green, blue-violet)

• colorblindness (color deficiency)

  • sex linked trait (more common in males)

  • red-green most common

  • potential advantage: recognize camouflage better

• can’t explain all aspects of color vision

  • people with normal vision cannot see color combinations

*both color vision theories are valid

opponent-process theory

• color vision theory where there are 3 pairs of color receptors (yellow-blue, red-green, and black-white)

  • members of each pair work in opposition

  • evidence: explains color afterimages

*both color vision theories are valid

color vision in other metazoans

• dichromats- mammals

• monochromats- rodents

• UV- bees

• many species are tetrachromats

opsins

• proteins that control hunting time in cnidarians (i.e. jellyfish)

  • arose by multiple gene duplication events

photoreceptors

• provide important information about the environment

• vision is under strong selection- strong advantage to increase fitness

ocelli

• insect vision

  • simple eyes that detect horizons and changes in light intensity

    • important for diapause induction, acclimation

    • no image resolution

  • analogous to parietal eye in insects

compound eye

• insect vision

  • compound eye

    • mosaic vision- visual acuity is greater when eye is small

    • ommatidium- one “eye” in the mosaic

      • includes corneal lens, cone, pigment cells, rhodopsin, photoreceptor cell

      • connect to axon that goes to the brain

what is the difference in the visible spectrum for humans vs. bees?

• bees see similar range as humans but more UV and less red logjt

  • impacts the color and shape of petals (bulging of petals due to eye shape)

bees and pattern recognition

• recognize brokenness or flickering patterns because they tend to land of flowers that shake in the wind

• optomotor response- flying insects can tell direction _ speed by observing the movement of patterns around them as they fly

  • movement perception

what is required for distance vision?

• binocular vision

  • human eyes converge on points in the distance

  • insects rely on different ommatidia to fixate on a point

disadvantages/advantages of compound eyes?

• each ommatidium has a small angle of acuity so better detection of motion

• not well suited to detect and differentiate contract

• redundancy of multiple lens- not a big problem

  • e.g. telescopes are compound- not single lens

sensilla

• (hair)- mechanoreceptor that responds during deformation with a charge from the nerve cell to the brain- usually only one cell receptor per sensilla for tactile sense

  • mostly found on legs, mouthparts, antennae, wings

  • highly developed in cockroaches- rapid transmission of nerve impulses because connected to giant axons- rapid movement by insect

taste in insects

• receptors occur body wide among insects

  • e.g.. wasps drill down to taste before oviposition larvae

taste in vertebrates

• gustation centralized to tongue

what is flavor?

taste + olfaction (taste and smell)

insect olfaction

• acute ability to smell because used to find hosts and mates

• olfactory chemoreceptors- on antennae- exposed to air, connected to dendrites, and sensory neurons

  • different receptors are narrowly tuned or broadly tuned to different odorants

insect olfaction

• respond to blends of gaseous volatiles- sensory cells that respond to only one chemical and some that can respond to more than one

  • behavioral responses searching for:

    • good food/avoiding unsuitable food

    • finding mates/staying away from unsuitable mates

  • search behavior- more upwind

how do male moths find the source of pheromones

what are pheromones?

• used by animals for chemical communication

  • information about identity and sexual receptivity

• stimulate vomeronasal organ- information is sent to special section olfactory bulb for pheromonal communication

sound waves

• changes in pressure caused by molecules of air moving

frequency

• number of cycles per second in a wave (measured in Hertz)

anatomy of the ear

• eardrum- tympanic membrane

• middle ear- 3 bones (malleus, incus, stapes)

• cochlea- fluid-filled inner ear

  • causes vibration of basilar membrane

  • vibration transduced into neural signal

• basilar membrane- membrane in cochlea which contains receptor cells (hair cells)

• auditory nerve- connects ear to brain

  • provides info to both sides of the brain

function: relay and amplify incoming sound waves

• amplification done by inner ear bones (ossicles) and narrowed channel

how do we localize sound?

• monaural cues

  • loudness (i.e. louder sounds are perceived as being closer)

• binaural cues

  • time of arrival (i.e. sound arrives at one ear before the other to indicate sound direction)

insect hearing

tympanum- specialized mechanoreceptor (analogous to human ear drums)

• found on legs, abdomen, thorax, and even wings

  • moths, mantids, neuropteran: allow to avoid predation from bats up to 30m away

  • homopteran, orthoptera, Hemiptera- finding mates

vestibular sense

balance

• semicircular canals connected to cochlea

sensory comparison in insects

• gustatory- highly specialized in insects

• olfaction- highly specialized in insects

• hearing- poor frequency discrimination

• visual- poor discrimination for contrast and high for motion

behavior

actions or reactions of an organism, usually in relation to the environment- conscious or unconscious, voluntary or involuntary

explain what Niko Tenbergen got the Nobel Prize for (hint: geese)

• ethology- study of behavior

• used simple experiments to understand behavior

  • e.g. fixed action patterns- game simple external cue can trigger behavior (hard-wired, instinctual- not learned behavior)- tested geese with different sized eggs to see if they still egg-roll

  • alarm vs. no alarm- no alarm does not trigger behavior

• proximate vs. ultimate mechanisms

proximate vs. ultimate mechanisms

• proximate mechanism- how

  • causation (mechanism)- what stimuli causes responses and how have responses been changed by learning

  • development- (ontogeny)- how does behavior change with age and what early experiences are necessary for the behavior to be shown?

• ultimate mechanisms- why

  • function (adaptation)- compare behavior to all other possible behaviors and evaluate benefits

  • evolution (phylogeny)- how does behavior change among organisms

    • e.g. sensory exploitation- eyespots on male fish attract females

instinct

behavior that occurs without previous experience

how did they discover landmark learning in insects?

nest homing experiment

• placed pinecones around wasp nest

• when they were gone Tinbergen moved the pinecones over

• wasp returned to the center of pinecone circle- not where the nest was

• conclusion: use visual landmarks to navigate rather than other senses (smell, memory, etc.)

explain the evolution of lethal aggression in non-human mammals

• traits in a clade are not independent so can use phylogeny to determine violent mammal clade

  • remove effects of relatedness

explain what Konrad Lorenz focused on in his Nobel Prize work (hint: bird)

• fixed action patterns- complex behaviors triggered by fixed action patterns

  • require sign stimuli- identify

    • evolve with courtship behavior

      • e.g. stickleback fish- shape

• ontogeny of behavior- imprinting + critical periods

  • e.g. bird song

explain the ontogeny (development from childhood) of bird song

1. sensory period- learning and exposure to song

2. sensorimotor- critical period of practicing song

3. song crystallization- song is set

• other example: immersion learning increases accuracy rate of learning- learning rate declines into teenage years- monolinguals have significantly higher accuracy than bilinguals

communication

transmission of information or disinformation among at least 2 individuals (sender + receiver)

• sent through the environment

• intent involved in communication (sender benefits from response of recipient)

what are reasons to communicate?

• mating + reproduction

• parental care/solicitation of care

• group cohesion- contact calls

• aggression + social status

• alarm + distress

• foraging- share food location

  • e.g. ravens feed on a carcass that they are alerted to by a yelling companion (recruitment signal)

• territory defense + conflict resolution

what are the channels of communication?

1. sound (hearing)

2. light (vision)

3. chemicals (olfaction)

4. electric field (electro-reception)

how is information transferred?

• signal perceived by receiver (despite any degradation of the signal as it travels through the environment)

• receive discriminates the meaning among signal variants

• signal transmission + efficacy depends on the sensory mode used to transmit

explain how the sensory modalities effects the distance, localization, ability to go around obstacles, rapid exchange, complexity, and durability of the signal?

Lombard effect

increasing vocal amplitude to minimize the masking effect of background noise

• e.g. impact of urbanization on birdsong (habitat-dependent shift: shorter duration of song in forest than in urban area- strong correlation of high minimum frequency and geographic location)

  • temporal divergence b/w urban and rural bird communities in song duration, time between songs, and duration of first note

  • changed call during covid because noise level in city decreased

what is the phyisiolocial limiation of vocal performance in birds?

• it is harder to chirp rapidly at a high frequency and wide bandwidth

  • i.e. greater trill rate = less bandwidth

is communication always honest?

no

honest communication- benefits both receiver + sender

• accurate information about state of sender- increases fitness of both

deception- benefits sender but possible detriment to receiver

• intra + interspecific

eavesdropping- benefits receiver but possible detriment to sender

examples of deceptive signals

• predatory signaling in fireflies- males flash to attract mates and females flash back to reproduce- females use deceptive flashes characteristic of another species to eat males that are decieved

• warbler feeding cuckoo chick- lab/recitation paper*

• predatory bats exploit frog mating calls to attract frogs (prey)

why are signals honest? (or what is the cost of dishonest signals)

• both parties benefit from honest communication

• sender is closely related to receiver so want to provide correct information

• signal production is costly- cost analyzed with benefit to sender

• signal production is constrained (i.e. size/frequency of call)- requires more energy to increase accuracy

  • e.g. higher strut rate of sage grouse increases their mating success

  • e.g. tradeoff of shuck rate and number in grasshoppers- occupy own bush but other grasshoppers intrude so shuck to warn off

explain Von Frisch’s Nobel Prize work (hint: bee)

honeybee dance language- symbolic communication in insects

• e.g. tail wagging and round dance

  • scout bees- communicate feeding place

    • longer waggle = further distance to feeding place

    • direction of waggle- degree of feeding place based on the degree of the sun

    • bees- have an inner clock using polarized light

  • scout bees

    • assure resource quality

    • measure distance + direction using optic flow

  • recruit bees- follow scout bees direction to food source

    • olfactory sense- learn the odor of the food source

      • the dance provides the general area of food but only the odor identifies the exact flower/food source

    • assess resource quality through acoustic cues provided by scout bees

• *figured out all this information in a series of experiments including the step by step experiment to measure distance (measuring how many bees settle at food source where the food has been removed) and fan experiment to measure direction (food sources arranged in fan around hive and the number of bees that visited each food source recorded)

optic flow

• counting objects as bees fly to count the distance in order to communicate accurately other bees

sensory physiology difference between scout bee and recruit bee in resource communication

scout bee

• resource quality- gustatory sense

• measures distance- visual sense

• measures direction- visual sense

recruit bee

• plant identity- olfactory sense

• resource quality- acoustic sense

• resource direction + distance- gravity, UV/visible light information on sun positioning

what experiment resulted in new findings about the bee dance?

• trained bees to either fly to food sources on land or to food sources on island (across water)

  • bees communicate less waggles over water than over land

• results: dance language directs them to the area

  • at near distances the flowers are located by olfaction

arguments for and against bee dance as a symbolic language?

FOR

• always performed in front of an audience

• communicative in nature

• rule-governed

• complex

• stability and dynamic

• symbolic

AGAINST

• genetically fixed rather than learned through environmental interactions

cultural inheritance

information passes across generation

• through observational learning

examples of cultural inheritance

• Lorenz- birdsong learning (dialects)

• potato washing in Japanese Macaques- taught entirely by Imo

• tool use in dolphins- using sponges to protect noses while foraging- mother-infant and between families

• tool use in primates- mother-infant learning

  • tool use patterns can be group specific- culturally inherited (not genetic)

• allogrooming

• aggressive behavior

chimpanzees vs. bonobos

chimpanzees

• north of Zaire river

• omnivorous

• males eat meat more than females

• tool use

• females disperse to new groups as adolescents

• males form cooperative bond

bonobos

• south of river in dense forest

• slender, long legs, smaller than chimps

• omnivorous

• no tool use

• male-male and female-male alliances

• highly sexed

• sex used for social bonding

• females solicit food for sex

gene comparisons of humans and chimps

• only 1% DNA sequence difference

1. structural gene differences (amino acid sequences)

   1. only hair and skin genes (not neurological or brain genes)

2. regulatory gene differences

how are humans differentiated from other animals?

predominance of culture- not culture itself- differentiates humans from other animals

• accumulation of information/material through generations

• new process of evolution- semi-independent of genetic evolution

cultural inheritance- MAJOR HALLMARK of humans

human cultural inheritance

• major component of human behavior

• proceeds independent of organic evolution

• genes = neural structure for cultural evolution

• spreads through populations by learning rules

hominid brain evolution

• rapid evolution of brain size- just recently tapered off

• massive increase for the past 1.5 mya in Homo erectus

  • potentially related to increased tool use, group hunting, social structure, cooking, etc.

parallel cultures

• odontocetes (dolphins, porpoises, belugas, etc.)- starting to demonstrate behavior faculties previously only attributed to humans and great apes

  • mirror self-recognition

  • comprehension of artificial, symbol-based communication, systems + abstract concepts

  • learning + intergenerational transmission of behaviors- culture

• brain size has increased in correlation with these capabilities

problem with increased brain size

• childbirth is impossible if head is too large

• born with underdeveloped brain so need more parental care

  • brain develops in teenage years

  • most neurons present but synapses not connected

  • altricial- offspring born in underdeveloped state so need more parental care

  • precocial- offspring born in well-developed state so capable of movement shortly after birth

metabolic cost of large brains

• brains require 15% of cardiac output even though it only makes up 2% of body mass

• modern human brain- 7x larger than expected for a primate of our size so the metabolic cost is roughly 7x larger

weather vs. climate

weather: day to day

climate: longer averages of weather over time

what is the difference between weather fluctuation along coats vs. the center of a continent?

• there are less temperature and weather changes throughout the year along coasts but more temperature fluctuation in the middle of continents (i.e. Kyrgyzstan)

where is the point of maximum heating?

• because the Earth is on a tilt, the sun’s rays are hotter differentially

  • the point on Earth that is closest to the sun = point of max heating

    • can be the equator but depends on the title of the Earth at the time

    • changes throughout the seasons

    • more variation in temperature further from the equator

what is the effect caused by Earth’s spin?

Coriolis effect- the direction of deflection depends on Northern/Southern Hemisphere

• no deflection at equator

• deflect to right in North

• deflect to left in South

what are the 3 global wind patterns?

• polar easterlies- North of 60

• prevailing westerlies- 30-60

• Tradewinds- 0-30

*2 dimensional

explain the three-cell model of global circulation system?

• the polar easterlies powered by cold air from the poles descending and warming up so that it then moves up again to form the polar cell

• prevailing westerlies powered by being in between the polar and Hadley cell receive dry air forming deserts forming the Ferrel cell

• Tradewinds powered by the heating of the earth around the tropics form the Hadley cell

*3 dimensional

what is ITCZ?

inner tropical convergence zone

why do the tropics have wet/dry seasons?

• the point of maximum heating varies along the ITCZ as the Earth rotates around the sun at a tilt

  • i.e. rainy season is always at the point of maximum heating at that time

mean temperature _____ with latitude

seasonal variation _____ with latitude

seasonal variation is _____ on land than sea

seasonal variation is _____ in Northern Hemisphere

decreases

increases

greater

greater (more land mass in Northern Hemisphere)

what is specific heat?

the amount of heat needed to raise the temperature of 1 gram of a substance by 1 degree Celsius

ocean currents on the surface

ocean currents influence temperature and wind- driven by Tradewinds and westerlies

thermohaline circulation

• global ocean conveyor belt

  • evaporation of warm surface water and influx of fresh water from melting glaciers- causes denser, salt water to sink to the ocean floor (deep water formation)- salt water = nutrient dense

  • flows along the ocean floor as cold saline deep current until it heats up to a warm surface current

  • heats to surface and releases heat- gulfstream releases heat to atmospherically warm Europe (i.e. why Barcelon is hotter than Rochester at the same latitude)

normal vs. El Nino year

normal year- connective loop so the ocean currents pull up cold water toward the surface to cool atmosphere

El Nino year- increased convection- less strong Tradewinds so doesn’t pull colder water up so stays warmer

upwelling

deep, cold, nutrient-rich water rises to the surface next to continents- driven by Tradewinds pushing the surface water away

what comprises a biome?

soil type + climate