Lectures pre M1 Flashcards
Animal
An organism feeding on organic matter, typically have specialized sense organs and respond rapidly to stimuli
What characterises animals (4 things)
- One of the 3 kingdoms of multicellular organisms (other two are plants and fungi)
- Feeds on organic matter
- Typically has specialised sense organs and a nervous system
- Able to respond rapidly to stimuli
The PQ4R method for effective learning
Preview the material and identify sections read as units
Questions for each section heading
Read while trying to answer the questions
Reflect
Recite the info and answer your questions
Review
3 multicellular kingdoms
animals, plants, fungi
Why study animal behaviour
- we are animals
- relevant to understand human behaviour
- to avoid some animals
Whooping crane video
- Have human foster parents
- Use crane puppets to feed so no humanization
- Humans dress up birds to help them fly
- Idaho farmer rears to avoid humanization
- Kent teaches them where/how to migrate in his microkite
- Population from 16 in 1954 to 600 wild birds in Canada
2 aspects of learning: Chicks imprint on caregiver, young learn migration routine from adults
Why do we enjoy having other animals around
- Humans have strong innate satisfaction from “friendly” species
- We extend our sociability to other “friendly” species
- They are important to our ecosystems
Why share earth with birds?
- Important to ecosystems and we enjoy having other animals around
What happens if no vultures
- Recent 95 % decrease in vulture pops due to poisoning
- Increase in human diseases and deaths bc vultures are sanitizers
How animals affect apples
- Pollination (bumblebees, honey bees, other)
- Pests (maggots, worms) -> ants protect from pests in return for sugar
- Biological control (some insects feed on flies, ex. Parasitoid wasps deposit their eggs into those of fruit flies)
- Seed dispersal (poop out seeds from fruits)
Fly learning and human mental health
- Memory-enhancing drugs and treatment of human learning disabilities
Fruit fly video - Tim Tully
- Similar genes to humans
- Tim Tully tests the memory skills of fruit flies
- Put room lined with electrical current
- Two tubes, one with a certain smell that alerts shocks
- If they train 10 times in succession, no long-term memory
- With rest interval of 15 mins, they form a long-term memory
- Flies with extra Creb gene can learn after only one training session = photographic memory
- Set switch on to convert more short term memories to long (Good for age-related memory loss)
Plane crash into Hudson river (2009)
- Everyone survived
- Bird tissues removed from plane engine = they were responsible
- Canadian goose and they identified where it came from; using hydrogen isotopes to see what they ate = came from Labrador
Use techniques like bird radar, robotic bird, and researching migration to avoid another crash
Applications of goose crash
- development of management techniques that could reduce the risk of future collisions
- for migratory vs. residential
Integrating this info with:
bird migration patterns
bird-detection radar
bird dispersal programs at airports can minimize such collisions
Bird-airplane collision prevention
- Airport control teams that do research to reduce collisions
- Israel research (birds don’t like to fly over open water)
reduced collisions by ~85% saved US $40 million per year - Bird forecasts showing migration intensity - planes can reroute
What is critical thinking
exercising thorough judgement or observation (analysing)
- does it make sense
- reasonable conclusions
- what issues remain unresolved
Takes time and effort
Ana”lysis” + elements
Breaking up a whole into parts; examining in details
- Purpose/Question
- Assumption/theory
- Data and facts
- Conclusions
- Implications/consequences
Intellectual standards
Clarity: can I understand it?
Accuracy: is it right or wrong?
Precision: can it be more specific/detailed/exact?
Relevance: is it sufficiently related to the issue?
Depth: complexities and interrelationships?
Breadth: multiple points of view?
Logic: does it follow from the evidence / make sense?
Significance: is it important?
Fairness: conflict of interest / biases?
Scientific method
- Define the question
- Gather information and resources
- Form hypotheses and testable predictions
- Plan experiments to serve as critical tests of the prediction using properly designed experiments by independent teams
- Do experiments and collect data
- Analyse data
- Interpret data and draw conclusions that serve as a starting point for new hypotheses
- Communicate results via peer-reviewed journals
Blind experiment
The person who collects the data does not know subjects’ assignment to treatments.
- Relevant for all science
- Bias is an issue
Double blind experiment
Both the data collector and subjects do not know subjects’ assignment to treatments
Caveat: often, people can guess..
- Relevant for human subjects bc were biased to ourselves
No-blind vs. blind bias experiment - with rats
In an experiment involving rats with similar abilities, non-blind observers will record higher performance for rats labelled bright than for rats labelled dull
Why blind or double blind?
2 reasons
- In all experiments, experimenter is always biased
- In human experiments, experimenters and subjects are biased
- In humans, there is a very strong placebo effect
∴ The only proper protocol for experiments with humans is double blind
Placebo effect - acupuncture
The expectation and anticipation of clinical improvement
Indicated by: large difference between sham treatment (placebo) and no treatment (same treatment)
acupuncture and sham (placebo) treatment both had the same score
Causes of observed improvements in the control treatments
5 reasons
- Spontaneous improvement
- Statistical regression to the mean = a statistical phenomenon that can make natural variation in repeated data look like real change
- Placebo effect (psychological factors)
- Biases (e.g. patient being polite)
- Co-interventions (e.g. pain killers)
Scientific approaches - ultimate vs proximate
Ultimate = Why?
- function
- adaptive significance
EVOLUTIONARY FORCES
Proximate = How?
- mechanism
- machinery (genetics, physiology, neurobiology)
- operate within the lifetime of an organism
NATURAL SELECTION
Sparrows experiment (edge of extingtion) - stress
Glucocorticoid hormones such as corticosterone have been linked to stress responses, so birds on the edge of the expansion (furthest from Mombasa), and hence in the most novel environments, would show the strongest surge in corticosterone when exposed to a stressor (especially during breeding season)
Invasive house sparrows experiment - proximate and ultimate answers
Proximate perspective (how): increased corticosterone leads to better memory of stressors
Ultimate perspective (why): the payoffs for better memory in environments with novel and unpredictable stressors should be greatest in leading edge populations during invasions
Ultimate analysis of plumage in the house finch (Geoff Hill)
Ultimate
- Why do males, but not females, actively search for carotenoid-based foods
~helps males obtain mates
- Why do females prefer males with bright plumage
~disease resistance, feed offspring more, better foragers
Proximate analysis of plumage in the house finch (Geoff Hill)
Proximate
- What causes between-population differences in female coloration
~availability of carotenoid foods
- What causes males and females to differ in plumage colouration
~different foraging strategies
Are hormones proximate or ultimate
a proximate cause
Endocrine system
a communication network that influences many aspects of animal behaviour (hormones released by either ductless glands or neurons)
- Primarily composed of a group of ductless glands that secrete hormones directly into blood
Major hormone-producing glands in vertebrates + what happens while they malfunction
- adrenal gland
- pituitary gland
- thyroid gland
- pancreas
- gonads
- hypothalamus
hyposecretion or hypersecretion affects functions like growth, metabolism, reactions to stress, aggression, and reproduction
Endocrine cells
where + what do they do
Cells within endocrine glands that synthesize and then secrete hormones
Neurohormones
Hormones that can be released directly into the blood by neurons (typically in the brain)
Hormones
act as chemical messengers, affecting target cells that reside some distance from the gland-secreting hormone
- same hormone can have different effects on different target cells
- almost always transported through the bloodstream and all cells (except one) in the body have a direct blood supply
Target cells + process of binding
cells with the receptor site for a particular hormone
- hormone has no effect on a cell unless the cell has the correct receptor
- hormone reaches the cell and binds to the receptor site
- a series of interactions occurs that affects gene expression and protein synthesis
- these changes and directly or indirectly affect an animal’s behaviour
Hormone-receptor complex
one sentence analogy
the receptor site (lock) on the surface of the cell is not activated until the correct hormone (key) reaches it
Birds - what causes release of a hormone into the bloodstream
and what hormones are increased
- Breeding season = spring/summer = cued by changes in day length
Day lengths increase → increase in levels of gonadotropin (sperm production) and testosterone (makes males more aggressive towards one another to get females, guard mates, build nests, and defend their brood)
Protein hormones
hormones made up of strings of amino acid
- can be stored in endocrine cells for delayed release
- hydrophilic (aq soluble) so they don’t need a carrier chemical
- larger = greater half-life
- most common hormone in vertebrates
If small: peptide hormones (ex. prolactin)
Steroid hormones
ex. testosterone
- can’t be stored = immediate release
- hydrophobic so they need a chemical chaperone to move them through the bloodstream
- bigger lag time between stimulus and production (compared to protein)
Ecotourism
is designed to draw tourists to beautiful ecologically endangered areas of the world, using the funds generated from this tourism to protect the wildlife in these areas, and to promote the local, often indigenous, human culture that lives around the ecotourism site
Magellanic penguins in Argentina - ecotourism & stress
- Adults exposed to tourists have habituated to their presence and show reduced defensive responses (and corticosterone) in the presence of humans vs with those not exposed
- Very young penguins exposed to tourists showed much higher levels of stress hormones (plasma corticosterone) than those from control groups
Why?
- in ecotourism areas habituated adults leave nest and spend less time brooding as they walk near humans
- causes stress + temperature change stress for chicks
Animals have three interactive systems
input output type
- Input system: made up of all the sensory systems (smell, sight, etc)
- A central processor: made up of integrators that process and integrate the sensory info received
- Output system: effectors such as muscles that move when stimulated
Hormones priming + testosterone example
prime animals so that they are more or less likely to behave in a specific way in a specific environment
ex. testosterone and winning a fight feedback loop
when baseline levels of testosterone are high, males are primed for aggressive behaviour when encountering another male (if they win a fight due to high baseline testosterone, this increases testosterone more)
Mouse fetus in development
if a developing male mouse fetus is surrounded by females, it’s exposed to lower levels of circulating testosterone, so it will be less aggressive and less sexually active than males that were surrounded by male fetuses
Fight or flight response
- Stressor (ex. predator)
- hypothalamus responds along two pathways
a. first pathway
- burst in epinephrine (adrenaline) and norepinephrine leads to an increase in blood sugar and oxygen delivered to vital organs
- nonessential systems (digestive, reproductive) are shut down
b. second pathway
The following hormones are released by the hypothalamus to increase sugars:
- corticotropin-releasing hormone (CRH): leads to ↑ cortisol
- growth hormone-releasing hormone (GHRH)
- thyrotropin-releasing hormone (TRH)
- Aldosterone production to increase water retention and reduce bleeding if the stressor causes injury
In Utero Exposure to Hormones - male gerbils
- testosterone levels in 2M males were significantly higher than in 2F males
Caused them to
-mount females faster and ejaculate sooner
- have more offspring
- spent less time with offspring after birth (less parental care)
In Utero Exposure to Hormones - female gerbils
Preoptic area of the hypothalamus (gerbils): controls copulatory behavior + is sexually dimorphic, meaning that males and females show different activity patterns in the preoptic area
- 2M females have preoptic metabolic activity that resembles that of males more than that of 2F females
- 2M females have 20 percent greater metabolic activity in the preoptic area of the hypothalamus than do 2F females
Vasopressin - what it does
important roles in social behaviours like reproduction + parental care in mammals
Prairie vs. meadow vole vasopressin
Prairie voles are monogamous:
- both males/females have a single mate each breeding season
- males display parental care and guard their mates
Reason: more vasopressin receptors in the ventral pallidum area
Meadow voles are polygynous:
- males mate with multiple females during a breeding season
- males do not display much/any parental care or prosocial behaviour towards mates
Reason: fewer vasopressin receptors in the ventral pallidum area
Experimental administration of vasopressin to male prairie voles increases monogamous behaviours, while administration to meadow voles does not b/c meadow voles lack the receptors to bind the extra vasopressin
NEED RECEPTORS TO GET MORE VASOPRESSIN
Honeybee foraging - hormones
when bees usually go from housekeeping to foraging for food outside of the nest, it is associated with an increase in juvenile hormone III (JH III)
- increase in JH III is correlated with the shift to the forager stage
- bees that had been allatectomized (and thus had no JH III) began foraging significantly later than bees in control groups, poor navigators, no other major behavioural changes
Octopamine
foraging honeybees
- Modulates learning + memory in honeybees
- Forager bees have higher concentrations of octopamine in their brains
- Octopamine reaches its highest concentration when a bee switches from nest bound activities to foraging activities (including foraging-related flight behaviour)
Plainfin midshipman fish - hormones
2 hormones
2 types
Type I
- males build nests
- 4x larger
- higher gonad-to-body size ratio
- produce sounds in many behavioural contexts: grunts when in aggressive contexts with other males, hums when courting females
- if selected as a mate, remains on the nest after a female lays her eggs there
Type II
- “sneakers”: they don’t build nests, but stay around the nests of type I males, then dart in and shed sperm in an attempt to fertilise the nesting female
- small
- lower gonad-to-body size ratio
- do not hum to attract females, rarely grunt
type I males: higher Kt (testosterone androgen) - associated with sound production - and lower cortisol
type II males: higher cortisol (glucocorticoids)
Plainfin midshipman fish - anatomy
AVT and IT
Midshipman’s vocal organ is a set of paired sonic muscles.
- innervated by “pacemaker” neurons
Type I males:
- larger sonic muscles w/ more muscle fibres
- pacemaker neurons fire at a rate of 15-20% higher than type II
- Arginine vasotocin (AVT) inhibits activity in the neurobiological circuitry associated with sound production
- Isotocin (IT) has no effect on sound production
Type II males:
- smaller sonic muscles
- pacemaker neurons fire at a lower rate
- AVT does not affect vocal motor activity and sound production
- IT inhibits activity in the neurobiological circuitry associated with sound production
Neuroethology
neurological underpinnings of behaviour (nervous system and behaviour)
Neurons
specialized nerve cells that have an axon and fire action potentials
- over evolution, neurons that served specific functions became clustered