Chapter 7 Flashcards
(83 cards)
Research 7.1: Improved Foraging Efficiency in Salamanders
1) Salamanders feed under rocks and logs on a wide variety of invertebrate prey
RED BACKED SALAMANDERS & FORAGING EFFICIENCY: Research Question and Hypothesis
Does their foraging efficiency improve with experience? Learning would improve salamander’s skill as predators
RED BACKED SALAMANDERS & FORAGING EFFICIENCY: Methods
a) Examined predatory skills of lab-reared two-week-old individuals with no prior foraging experience
b) Standardized hunger levels by doing three feeding trials (separated by 14 days)
c) Presented four termites and recorded capture attempts, successful captures, and the number of prey that escaped after capture
RED BACKED SALAMANDERS & FORAGING EFFICIENCY: Results
a) Neonates captured few prey in the first trial
b) Capturing ability improved in the subsequent trials
c) Individuals rapidly learned to forage in a more efficient manner as they gained experience
T or F: researchers wondered if learning is always adaptive and a long-standing answer was that evolution should always favor improved learning ability but the answer may be more complex
True
What does Learning Theory teach?
a) That two factors affect the evolution of learning: the regularity of the environment and the reliability of past experience
b) As environmental regularity increases, learning will become less favored
c) As reliability of experience increases, learning will be strongly favored since individuals that learn will have higher fitness
d) The real world falls between the two extremes: a dynamic world where reproduction in each habitat can vary or a fixed world where only one habitat leads to high fitness
Research 7.1: Fiddler Crab Habituation
a) Habituation: the reduction and then lack of response to a stimulus over time
b) Stimuli can be biotic or abiotic and any reaction to a stimulus is a response
c) Crabs leave the safety of their underground burrows to forage and mate, exposed to predation by avian predators
d) Previous worked showed that crabs habituate to nonthreatening humans but do they habituate to other objects
FIDDLER CRAB HABITUATION: Methods
a) Dummy predator was placed in a fixed location
b) The researchers would move the dummy over the crabs for 1m and then returned it to its initial position (runs)
c) Video cameras recorded whether the crabs responded by running toward their burrow and if they went back into them
FIDDLER CRAB HABITUATION: Results
a) On the 1st run, almost 100% of crabs ran into their burrows
b) After 14 runs, fewer than 60% of crabs responded, showing a dramatic decline in response behavior, evidence of habituation to the dummy predator
c) Crabs closer to the dummy entered the burrow more frequently than crabs further from the dummy
Research 7.2: Neurotransmitters and Learning in Chicks
a) Imprinting: rapid learning that occurs in young animals during a short, sensitive period and has long-lasting effects
b) Greylag geese hatchlings imprinted on Konrad Lorenz’s boots since they were the first object they saw
c) In the brains of domestic chickens, the intermediate and medial parts of the hyperstriatum ventrale (IMHV) play an important role in memory related to imprinting
CHICKS & NEUROTRANSMITTER RELEASE: Research Question
Is the release of neurotransmitters from the presynaptic neuron associated with imprinting learning?
CHICKS & NEUROTRANSMITTER RELEASE: Methods
a) Half of chicks were trained by exposure to a visual imprinting stimulus while the rest were the control group and had no visual stimulus
b) During imprinting training, birds would attempt to move towards the stimulus with a running wheel recording these measurements
c) They measured the strength of imprinting by placing an imprinted object in front of them and a novel object
d) Killed the chicks, dissected IMHV tissue and conducted assays to measure the release of neurotransmitters
CHICKS & NEUROTRANSMITTER RELEASE: Results
a) Found higher glutamate in the IMHV tissue of trained chicks compared to the controls
b) There was no difference in GABA
c) However, among the trained birds, chicks that most strongly imprinted on the test object had higher levels of GABA in their brain
d) Glutamate was more strongly released in the brain of birds that visually imprinted on an object, while GABA was correlated with the strength of imprinting
Research 7.2: Dendritic Spines and Learning in Mice
a) Neural Plasticity: structural change in the number of synapses and strength of chemical synapses between neurons
b) Synaptic connections are dynamic due to dendritic spines: small protuberances on a dendrite that typically receive synaptic inputs
MICE & DENDRITIC SPINES: Research Question
Does the dynamic nature of dendritic spines play a role in learning?
MICE & DENDRITIC SPINES: Methods
a) One group of mice learned a new motor skill: running on a rotating rod suspended above a cage floor
b) Another group received no training and served as controls
c) They used transcranial two-photon microscopy to examined fluorescent-labelled dendritic spines of living subjects
MICE & DENDRITIC SPINES: Results
a) Both young and old mice that learned the new motor skills showed significantly higher levels of dendritic spine formation
b) The performance of mice on the rotating rod was associated with the number of new spines formed
c) Over two weeks, most of the new spines disappeared
d) Lifelong memory may be associated with the formation of new spines during learning (more research is required)
Research 7.2: Avian Memory of Stored Food
a) Caching food for the future is only useful if the food can be relocated
b) Some rely on local landmarks, like rocks and logs, but most use their memory
c) Corvids and Parids are common species that cache food, with some relying heavily on caching and some not so much
d) If cache recovery is accomplished through memory, species that cache heavily should rely more on a well-developed memory
AVIAN CACHING BEHAVIOUR & HIPPOCAMPAL FORMATION: Research Question
Does brain structure differ between birds that do and don’t need to remember the location of cached food?
AVIAN CACHING BEHAVIOUR & HIPPOCAMPAL FORMATION: Hypothesis
Hippocampal formation (HF) size in the brain correlates with spatial memory capability
AVIAN CACHING BEHAVIOUR & HIPPOCAMPAL FORMATION: Methods
a) Assembled data on HF size for 13 species of corvids and ten species of parids, adjusted for differences in body and brain size
b) Characterized species as: (1) a non-hoarder, (2) a non-specialized hoarder that caches food occasionally, or (3) a specialized hoarder that relies heavily on cached food for survival
AVIAN CACHING BEHAVIOUR & HIPPOCAMPAL FORMATION: Results
In both families, specialized food hoarders had larger HF size than species that rely less heavily on cached food, species that do not cache food exhibited the smallest HF
Classical Conditioning
a) The ability to learn new associations between a stimulus and an innate, or unlearned response
b) Begins with an innate response to a stimulus, like salivating in response to seeing food
c) Unconditional Stimulus (US) is food and the Unconditional Response is saliva
d) The Conditional Stimulus (CS) is a bell which was rang in association with the food and the Conditional Response (CR) is saliva
e) A dog would salivate after simply hearing the bell, even in the absence of food
Research 7.3: Pavlovian Conditioning for Mating Opportunities in Japanese Quail
a) They studied how classical conditioning affects mating behaviour in Japanese quail, medium-sized Asian birds commonly raised in captivity
b)