Midterm - Topic 1 Flashcards
Example of roles animals play in our society
- Agriculture
- Medicine: behavioural changes can reflect the effects of neurochemical agents, neurotoxins and hormonal changes. –> you can more easily study this in animals rather than humans
- animal research done on cognition memory and learning
- Entertainment
What do cave paintings tell us
- understanding animals has been important for a long time
- cave paintings dictate size, species, and human interactions
- helpful for new people in the area to know what surrounds them
Animal Behaviour Definition
- internally coordinated, externally visible patterns of activity that responds to changing external or internal conditions
- Behaviours are generate (within) as a response to changes in the environment
- Changes can come from the external environment or internal environment
- -> for example temperature change can cause an animal to move into the shade
- -> testosterone makes male giraffes more aggressive
Internally coordinated
Internal information processing
eg. endocrine signals, sensory processing
ex. giraffes during mating season have an increase in testosterone levels which help maintain the aggressive behaviour needed to fight for a mate and defend their territory
Externally visible
- patterns we observe and measure
- patterns that are visible
- -> example. measure the amount of giraffe testosterone and observe the aggressive behaviour
- doesn’t have to be observable by the naked eye, eg. you can use a microscope
- example, you can see a squirrel eating but you can’t see a lizards heart beat
Causally related (humans vs. animals)
In humans, you do not say that testosterone causes increased aggressive but we do say that in animals
Ectoderms
Animals that are dependant on external environment for regulating internal body temperature
Ethograms
formal inventory/description of the different behaviours an animal exhibits
-measure frequency, duration, rate(frequency/min) –> rate = intensity
Time Budget
related to ethograms
-total time and relative frequency of each behaviour
Animals and stress
Animals experience stress in captivity and in the wild. The types of stressors change but the animals still experience stress.
Ethograms are used in captivity and in the wild, to study stress behaviour
Ethograms Elephant (methods)
- recorded behaviours every 5 minutes in captivity, for an entire day, once a week for 11 weeks
- arbitrary, researchers went out when they had the time –> important to document as much information as possible so it is clear for others
High frequency behaviour seen in elephants
Dusting: collecting and throwing soil over them and rubbing into their skin while standing or walking
Feeder Ball: feeding or attempting to feed at a metal feeder ball containing small quantities of food
Locomotion: walking (not included for feeding and stereotyping)
Stereotyping is a high frequency behaviour.
Low frequency behaviour seen in elephants
Aggression: hitting, pushing as a result of antagonistic encounter (not play)
Digging: digging in the ground using foot, but not as a dusting behaviour.
Rolling: rolling around in soil or mud
What is stereotyping behaviour
- Repetitive behaviour with no obvious purpose
- Indicates stress
- Important to catch these behaviours so you can figure out if the animal continues to feel stressed
Results from the elephant study + conclusion
- the elephants spend 1/4 of their time feeding
- stereotypic behaviour is negatively correlated with feeding behaviours
- conclusions: using widely spread feeders to supply food slowly at random times in the day could reduce stereotypic behaviours
- -> since they are negatively correlated, if there is an increased time spent in feeding behaviours, there should be less stress behaviours
Onset of maturity in female mice. Mouse Uterus layout
- A mouse uterus has 2 horns with 6 locations for babies
- -> any sex can be in any of the places in the uterus
- researchers trying to see if female baby placement will influence when it reaches sexual maturity
Mouse. Female in uterus beside 2 males vs. 2 females
2M♀ will reach sexual maturity later than a 2F♀
- this is because the blood circulates through the entire uterus
- the 2M will produce testosterone, some of which will be picked up in the blood exposing the ♀ to the testosterone
Mouse. How did the researchers know which were the 2M♀ and which is the 2F♀
- close to the due date, they gave the mouse a C section and tagged the babies accordingly
Mouse. Ethograms used to test female sexual maturity
- a new male mouse was placed with 2M♀ females and 2F♀ females. If the female tried to mate, it indicated she had reached sexual maturity
- Behaviours tested for the ethogram:
1. Mate mounts: male climbing onto the female
2. Lordosis posture: female immobility after after being mounted with hindquarters raised allowing potential penetration
3. Biting gestures: teeth directed @ male, not necessarily pinching the male skin –> females are aggressive whether sexually mature or not
4. Freezing response: immobile without raising hindquarters
Mouse. Why do behavioural ethograms to test this instead of other methods
Other methods include taking various blood samples. This can cause a lot of stress. An ethogram is a way of testing behaviour without causing as much stress
The Scientific method
Formalized way of knowing about the natural world
Observation –> research question –> research hypothesis –> prediction –> method to test prediction –> analysis of results
–> Data did match prediction or data did not support prediction –> if did not match prediction, formulate another research hypothesis
How to advance knowledge in the field of research
- formulate research question based on careful review of the literature
- generate hypothesis
- generate an experiment using a paradigm an methods, incorporating design controls
- -> paradigm is an experimental set up - obtain ethics approval
- collect data with random sampling and random assignment
- analyze data and formulate interpretation using statistical tools
- communicating results
- generate next research question based on results
What is a research hypothesis
- An explanation based on assumptions that leads to testable predictions
- Hypotheses can be directional or non directional
- There is a null hypothesis and an alternative hypothesis
Null vs. Alternative Hypothesis
Alternative (Ha): the proposed explanation for the observation does have an effect
Null (H0): the proposed explanation for the observation does not have a significant effect. There is no difference between the two groups
Directional vs. nondirectional hypothesis
Directional alternative hypothesis: predicts specifically how the variable under examination will affect the particular behaviour
–> ie. behaviour will increase or decrease
Nondirectional alternative hypothesis: offers no specific prediction of how one variable will affect the behaviour
How do we test hypothesis
Descriptive: to develop descriptions of the phenomenon
Correlational: is there an association b/w the two variables, do they vary together. can be positively or negatively correlated
Experimental: using independent (manipulated) variables and examining the dependant variable (measured)
Correlation
- two variable vary together
- can change in the same direction (ie both increase or both decrease) which is called positive correlation, or they can change in opposite directions (ie. as one increases the other decreases) which is called negative correlation. Or it can have zero correlation.
Causation
- when one variable causes the other
- NOTE correlation does not mean causation
- it is very difficult to establish causation because you would have to rule out all other variables
P value
we look at the results in statistical terms to determine if the result obtained is significant, meaning that there is a less than 5% chance that the data obtained was by chance
p < 0.05 then the data obtain was significant
Random sampling and random assignment
Random sampling: participants randomly selected to give a good representation of the population.
Random assignment: subjects in the experiment are randomly assigned to the different groups (ie. control vs. experimental group)
Peer Review Process
A scientific paper submitted will be reviewed by peers to evaluate the merit of the paper. Often papers are rejected many time before being publish
Primary Source and examples
Primary literature has been peer reviewed
ex.
- Primary research articles in peer reviewed journals
- Dissertations
- Technical reports
- Conference proceedings
Secondary sources and examples
Secondary literature had been reviewed but not necessarily peer reviewed
Someone summarizes the findings of others.
ex.
- Monographs: books dealing with specific areas of research
- literature reviews
- magazine articles – even if the scientist wrote the article, the review process is different and it has not been reviewed by peers therefore is not primary
What is an impact factor
Each journal will produce and impact factor. The impact factor refers to the number of scientists that use this journal in their reference list. Number of citations found in other research journals
Why are control groups important for experiments?
Control groups are important to make sure that the effect of the independent variable is isolated.
Robin abundance and food availability
Research question: Why is there variation if the number of robins feeding in yards?
Hypothesis: the amount of food in a yard determines the number of robins feeding there
Prediction: the more food found in the yard, the more robins will be in the yard
Methods: The number of robins in each yard were counted. Then they examines how much food was in the yard in a specific area by mixing worm food together and pouring it over the soil and counting how many worms came up
Reject or fail to reject
When making conclusions, we do not say definitive words like proved, we use words like support
You can either say that you reject the null hypothesis or you fail to reject the null hypothesis
Wolf Spiders difficulty finding mates
It is hard for a male wolf spider to find a female wolf spider for a few reasons:
- after a female wolf spider has matted, they do not mate again
- females are cryptic meaning they blend in with their surroundings
male spiders will use chemical cues that females deposit on their webs to find them. Once a female is found, the male starts a courtship dance. This dance is attractive to the female but can also attract other males.
–> tap their leg and run their specialized organs together (seismic cue)
How do male wolf spiders attract unmated females (hypothesis, prediction H0 and Ha)
Hypothesis: male wolf spiders use the behaviour of nearby wolf spiders to find females
Prediction: the presence of rival males will result in the searching male to orient towards the rival and then begin courtship
H0: male wolf spiders do not use the other males to find receptive females
Ha: male wolf spiders use the behaviours of nearby males to find females
Some ways male wolf spiders attract females
Visual cues: larger males are preferred to smaller males
Seismic cues: tapping their foot, females will feel the vibrations
Wolf spider test
Juvenile males were taken from the wild and raised in captivity until sexual maturity.
The visual cues, seismic cues and both together were measured pre exposure (before female was seen), during stimulus exposure (while seeing female) and post exposure (after female was taken away)
The number of bouts (number of times each behaviour occurred) and mean duration for the bouts was recorded
wolf spider conclusion
There were no difference in seismic cues before, during or after exposure. The problem was that the males they collected had never had a sexual experience. The spiders need to learn from other males.
Part 2 of spider experiment
This time, the males were used as a stimulus
The juvenile males were presented with other males and the juveniles behaviours were once again measured, same as before but with an adult male as the stimulus.
The results were the same, there were no difference in the responses.
The conclusion is that the spiders need to have prior sexual experiences to display these behaviours
How long should a male spend mate guarding a female
Assumptions:
- Male fitness increases with number of fertilized eggs
- some males are more attractive to females than others
- once mated, some females sometimes/always/rarely mate with other males
Conclusions:
- the attractive males shouldn’t spend energy on females that are always faithful or on the ones that are never faithful. They should spend the most energy in the middle
- the unattractive male shouldn’t spend time with the unfaithful or faithful. There is a point where they should just give up because there is too much energy for someone who is likely going to cheat.
REFER TO GRAPH
Both spend most energy in the middle, but the unattractive males spend more energy than the attractive ones.
The UA will give up sooner than the A as the faithfulness of the female decreases
Both spend little E on the never faithful and always faithful ones
Anthropomorphism
when you attribute human motivations, characteristics and emotions to animals
does not produce testable hypothesis but we should not dismiss the possibility of animals having emotions
What causes birds to migrate and why do they migrate
- seasonal changes in day length can trigger hormonal changes that lead to increased feeding, fat storage etc
- in some species migration is genetically wired where in other species it must be learned
- they migrate to track resources
- migration patters may differ between populations of species and closely related species
Crying proximate and ultimate explanations, textbook
Proximate
What is the mechanism that causes the behaviour?
–> common trigger for infant crying is hunger, pain, separation from adult
How does the behaviour develop?
–> Infants cry at birth, and the crying peaks at 6 weeks then slowly declines till 4 month where it plateaus until around 1 year. First half of year, crying happens when they are separated, but not as much after 6 months
Ultimate
What is the function?
–> crying is metabolically costly and may attract predators but it is a form of communication that elicits a beneficial response from the care taker
How did the behaviour evolve?
Vocal chords produce vocalization which elicit a beneficial response from the caretaker, leading to survival.
Wolf Spider experiment according to the textbook
Hypothesis: male wolf spiders use the behaviour of nearby wolf spiders to find females
Prediction: the presence of rival males will result in the searching male to orient towards the rival and then begin courtship
H0: male wolf spiders do not use the other males to find receptive females
Ha: male wolf spiders use the behaviours of nearby males to find females
The juvenile male spider were caught from the wild and raised in captivity. These are called the focal males. The focal males were then exposed to an adult male who was previously exposed to the web chemical. The adult male was therefore performing the courtship dance.
The focal males were exposed to the adult male just tapping, or just vibrating or both together. The focal male was observed for their chemoexploratory behavior (slow walking and rubbing as a sign of them detecting the chemical signals), it’s courtship/behavoirs to attract the male (rapid walking and rubbing)
Results: None of the treatments had an effect on the focal males chemoexplore behaviours.
Conclusion: male wolf spiders do not appear to use the visual and seismic cues of rival males as a cue to locate females.
HOWEVER they found a few years later the same spiders in the wild doing what they had predicted. Could prior social interactions be an important prerequisite?
A similar experiment was performed using adult males caught from the wild.
This time their results were what they expected
Conclusion: male wolf spiders indeed used the cues of other males as a cue for finding females.
Mathematical model squirrel
Some squirrels are seen eating in the open while others run back to their tree.
Hypothesis: Food carrying might represent a trade-off between feeding in safety (in a tree) and obtaining highest energy intake.
Created a mathematical model with 2 variables: energy intake(e consumed per sec) and the probability of being killed by a predator
Model assumes that squirrel fitness increases as E intake increases and that the tree is safer than the ground
Prediction 1: the larger the food item, the more often it should be carried to the tree.–> assumes that larger food items require more handelling time (amount of time required to manipulate the food so it is ready to eat).
Prediction 2: as the distance between the food patch and the tree increases, individuals should reduce their carrying. (as distance increases, the amount of food the animal should carry decreases).
Methods: Put cookies at varying distances
Results: at each distance, they carried the larger pieces back more frequently. They rarely carried smaller items, they ate them in the field. They also carried fewer items to the tree as the distance increased.
The data matched both predictions.
Conclusion: food carrying behaviour in squirrels indeed represented a behavioural trade off between maximizing energy intake and minimizing predation risk
this is true for many species
Mathematical models
Source of hypothesis and prediction
Analytical model
Resulting models can generate predictions about which behaviour maximize an individuals fitness
Advantage: allow scientists to easily manipulate their assumptions to produce new predictions about a behaviour
Project Seahorse
Amanda Vincent studied seahorses
Spent many hours conducting observations.
Question began with the mating of seahorses –> are they monogamous and do males defend territories
Some are monogamous, which is rare in the animal world
Mated pairs greet each other in a daily ritual that seems important to maintaining the bond
Found that the seahorse population is decreasing because they are used in Chinese rituals and medicine.
In response, Project Seahorse was founded to protect the seahorses while also ensuring sustainable livelihoods of those dependant on seahorse fishing.
