Comparative psychology – relate to phylogenetic history
- Comparative: comparing one species to another.
- It is perhaps not fair to compare humans to animals because they have a niche that they
- There are species of animals that can do things that we can’t do and vice versa.
- First modern scientist to say that we should look at behavior: DARWIN.
- Ontogeny recapitulates phylogeny.
- Phylogeny: biology and evolutionary history.
o How closely you are related to each other in evolution, including genetic
o 99% of chimps’ genes are similar to ours.
o Anatomy is comparable as well.
o The closer they are to us, the more similar the phylogeny.
o Ontogeny: human development from fetus onto adulthood
o Phylogeny: evolutionary development.
o In the initial stages of development, the fetus resembles a fish.
o In fact in early stages, it looks like we have a tail?
We lose the tail as we have adapted to a non aquatic environment –
Analyze across four perspectives
1) How common are the behaviors across species?
- Do other species have emotions?
- Can they learn things? Memory.
- Do they have preferences, motivations?
- Do they have a sense of self?
- The closest the species are genetically to us, the more common their behaviors are.
2) How successful are the behaviors?
- In what niche does that organism live in?
o Talked about bats – live in caves. They are very successful because the
adaptation has been echolocation.
3) What mechanisms are involved?
- What mechanisms seem to differ significantly between species? The difference is in their
o This is the one mechanism that is most important for adaptation.
4) What is the ontogeny (development) involved?
- We are a cognitively advanced species.
- Elephants have the longest gestation period – 2 years.
- We have to learn a lot of things.
Brain size: Does cognitive ability reflect brain size? NO
- Are we more cognitively superior?
- Clearly, our brains are bigger than the brains of birds.
- We don’t have the biggest brain in the animal kingdom.
- The biggest one is whales – blue whales and humpback whales. - Their brain control behavior and movement and therefore they need bigger brains.
- Is it the proportion of the size of the brain to the rest of the body?
Cephalization index (K)
- The percentage of the body that takes up brain size.
- What makes us different from other animals?
- It is not the brain size but the cortex that makes us different and produces higher level
- Cortex (control cognitive intellectual functioning), thalamus and some parts of the limbic
(emotion and memory) and ganglionic system
- Midbrain – motivation
- Hindbrain –HR, motor coordination, sleep cycles.
Spinal cord –