Evolution and behaviour Flashcards
What is the encephalization quotient?
What proportion of body weight is taken up by brain weight
T/F: humans have the largest relative brain size
TRUE. Humans have the highest observed brain:body ratio
A crossbill’s beak is specifically designed to open pine cones. This behaviour is __________
INNATE
A baby roof rat must learn from its mother how to eat pine cones. This behaviour is _________
LEARNED
Which strategies will help organisms thrive in stable and unstable environments (innate or learned)?
- In stable environments, “specialists” like crossbills with INNATE behaviour will thrive.
- In an unstabke/changing environment, LEARNERS like the roof rat will thrive. Aka, GENERALISTS.
Which evolutionary strategy requires a larger brain: generalists or specialists?
Generalists due to higher plasticity and ability to learn. Trial and error.
HIGHER LEARNING = HIGHER ABILITY TO EXPLOIT OTHER RESOURCES TO SURVIVE
Evolutionary princliples
- Competition: more offspring than can survive/reproduce successfully
- Variation: sexual reproduction and mutation ensure non-identical offspring
- Adaptation: individuals whose characteristics are best fitted for environment will survive to produce more offspring
Functionalism states that:
Behaviour (not only physical characteristics) is subject to evolutionary processes. Therefore, each behaviour has a PURPOSE. ie. enables some aspect of survival, or it would not have evolved in the form that it has.
Why are “birds so dumb because they can fly?”
the inability to fly makes the organism have to develop intelligence to problem-solve to avoid predation.
give an example of a maladaptive trait
albino alligators can be easily seen. Easier for other predators to see them and harder for them to hide from unsuspecting prey
Homology vs Analogy
Homologous structures: same evolutionary/genetic/developmental origin, even if functionally different.
Analogous structures: serve same function, but not necessarily homologous (ex: wings on insect and bird)
Natural selection operates at the genotypic/phenotypic level (select one)
PHENOTYPIC
What is the significance of rift valley?
- separate tectonic plates
- each side has diff climates with diff species
- diff environments lead to diff foraging strategies
How is climate change a possible critical factor in human brain evolution?
Because drought caused humans to migrate to new environments
Why is bipedalism a possible critical factor in human brain evolution?
because it requires less energy than running on 4 legs/more energy efficient
Why is the development of grasping hands a possible critical factor in human brain evolution?
Because limbs not dedicated to locomotion could now be used for other things (ie. tool-making, fine movements, etc.)
Why is language a possible critical factor in human brain evolution?
Because language development = useful for social structure, relationships, and culture formation
What is neoteny?
Juvenile characteristics extended into adulthood
-A slowing of the process of maturation, allowing more time for growth; an important factor in the development of large brains.
T/F: adult human skull looks more like the skull of a chimp fetus than an adult chimp skull
True
Why have humans evolved to give birth to such helpless and vulnerable babies?
Benefit of having a large brain is greater than the cost of having a helpless baby.
Childbirth is difficult because the baby’s cranium is too large for bipedally-evolved mother. Therefore, women must give birth after 9 months while baby’s head is still relatively small, rendering the baby helpless for a time while brain continues to develop.
How has neoteny proven useful in the evolution of the human brain?
Flatter face and larger skull allows for larger brain and ability to express/communicate emotions
What do sociobiologists study?
social behaviour in non-human animals and they make comparisons across species.
Why is it beneficial for humans to have such a long period of life before reaching sexual maturity?
- BRAIN PLASTICITY greatly decreases at SEXUAL MATURITY
- longer infancy allows for strengthened brain pathways and LEARNING. Brain changes as we learn
- Having a more plastic brain gives us an advantage among other species
Cognitive demand of human society
We have to learn and remember the following:
- individual identities
- roles
- rules
- scripts (things that we are and aren’t allowed to do are scripted. Rules that we all know. Requires mental capacity)
Give an example of a static role and a situational role
static role: mother/daughter
situational role: customer/teller
2 things to process in a social encounter:
- situation
2. individuals (ex: know what topics to avoid and have a sense of how a person is feeling)
Where are mirror neurons located?
Mirror neurons are located in the ventral premotor cortex and inferior parietal lobule
When do mirror neurons respond?
When an individual makes a particular movement or sees another individual making that movement
