Evolutionary: Comparative

The Evolutionary Approach

The Evolutionary Approach

All of our cognitive abilities are direct or indirect products of our earlier environments and have evolved in response to physical needs and social demands.

Two Approaches:

Click on each to see a definition...

Comparative Cognition

Evolutionary Psychology

Overview of Evolutionary Principles

Natural selection is the process by which animal species change over time. There is variety in physical traits (small or large ears, etc). Parents pass on their traits to their offspring, called inheritance. A change in environmental conditions make it more likely that a species with certain traits will survive long enough to mate.

Overview of Evolutionary Principles

Adaptation is the process by which an animal species changes in response to the environment. Natural selection principles are concerned only with survival, which is if an organism lives long enough to reproduce. Sexual selection refers to the adaptation of traits that help an organism attract a mate and reproduce.

Comparative Cognition: Object Permanence

What is Object Permanence?

What animal species have object permanence?

Comparative Cognition: Memory

Memory is a very important adaptive capacity. It helps animals remember where they have looked for something, so that they don't expend valuable resources looking for it in the same place twice.

Comparative Cognition: Foraging

Foraging skills are crucial to an animal's survival. There are statistical regularities in how animals search for food in an environment. Spider monkeys, penguins, turtles, and tuna make many short distance movements, then one long distance movement, and again many short distance movements in that new location. This same statistical pattern is how humans make eye movements when looking at an image of a busy street.

Comparative Cognition: Transitive Inference

What is transitive inference?

What animals have this ability?

How did this evolve?

Evolutionary Principles and Artifical Life

This is an intersection of Evolutionary Processes and Artificial Intelligence. Alife researchers produce artificial "creatures" that live in virtual environments. They evolve according to evolutionary principles.

Comparative Neuroscience

How does brain size differ among species? Does a bigger brain mean an animal is smarter? Humans have smaller brains than elephants, but we know humans are the more intelligent species. What we need is the cephalization index K, or the ratio of brain to body size. Higher values mean that those species have a larger brain relative to their body size. Humans have the highest K value at .89, followed by dolphins at .64. Primates and whales follow with values between .2 and .3.

Comparative Neuroscience

However, this K index may not be the best measure of intelligence. There are other factors that influence brain size besides intelligence. Birds need to weigh less and have smaller brains, dolphins swim in the water and can afford heavier brains so they are bigger. Not all brain regions are involved in cognition. The neocortex is most closely correlated with cognition. However, not all animal species have a neocortex, only mammals.

Comparative Neuroscience

Neural connectivity is another possible measure. Humans have more connections than monkey and cat brains. However, a mouse brain has very dense connections as well. Number of nerve cells is another possibility. Dolphins have high cortical volume but low number of brain cells. Humans have smaller volumes but more neurons.

Evaluating the Comparative Approach:

There are methodological issues in evaluating the comparative approach. Many studies of cross species animal abilities have different experimental techniques. Some studies are done in artificial laboratory settings, while other are in natural habitats. People attribute humanlike characteristics to animals, known as anthropomorphism. Anthropodenial is the blindness to the humanlike characteristics of animals, or animal like characteristics of humans.

This helps social animals understand social hierarchy. If chimp A is dominant over chimp B, and chimp B is dominant over chimp C, then chimp A is dominant over chimp C

Apes, monkeys, cats, dogs, and some birds have object permanence. Dogs will look for a favorite toy that is hidden behind one of three boxes. This ability develops in human children by 12-18 months.

Transitive inference is deductive reasoning: if A is bigger than B, and B is bigger than C, then A must be bigger than C

Animals such as Kholer's chimps can also reason and solve problems: they were able to reason that a box and a stick could be used together to get food. Pigeons also demonstrate this understanding

Object permanence is the ability to understand that objects still exist after they are removed from view. This is a critical survival skill to understand that another animal still exists even if it is hidden behind a rock.

The Hawaiian nectar-feeding honeycreeper can remember which flowers it has collected nectar from and will not go back to those same flowers again.

Comparative Cognition: This approach examines the similarities and differences in cognitive abilities between different animal species. For example, birds that have to store large amounts of seeds will have a better memory than animals that don't need to do this.

Evolutionary Psychology: This approach examines how the human mind has come to be, and the forces of selection that shaped it. A related field is behavioral economics, which focuses on how evolution has shaped how we make decisions.