7/27/2019 Assignment - Lab #1

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Jordan Dunville (1167306)

Dr. Bruce Bolster

PSYC-2900-003L

September 19, 2013

1. What is the evolutionary explanation for warblers being so good at discriminatingeggs and so poor at discriminating chicks?

The cuckoo produces eggs that are almost identical to the warblers eggs in order to

infiltrate the nest and receive food. However, the warblers brain has been equipped

mentally and perceptually to detect the orphan egg and uses great visual ability to remove

it from the nest.

Evolution has equipped brains with a specific skill set and not others. In the case of the

warbler, while the mother is able to accurately detect an intruder egg it has not beenequipped with the proper skills to determine if the chick is of different descent.

2. Find and describe another example from a nonhuman species where the brainpossesses specific skills but not others. What would be the evolutionary explanation

in this case?

Salmon reproduce in rivers and then travel out to the ocean in order to gain body mass.

After they have matured they return to the location of where they were born in order to

begin another cycle of reproduction. The moment they return is called the Salmon Run.

Predators eliminate most of the population and the cycle starts again.

In this case Salmon being able to return to their birth place to reproduce is an innate

behaviour they have been equipped with. However, they do not conceptualize the fact

that if they return their population will be almost eliminated by predators.

3. In the film there are examples of a particular trait (physical, physiological, orbehavioural) being adaptive in one environment but not another. Find another

example and explain why this would be so.

Wisdom teeth were used to crack nuts and grind down plant tissue because of cellulose.

As humans evolved tools were created to break down plant tissue and crack nuts.

Wisdom teeth lost their purpose because of the improvements of technology in the human

environment.

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4. Describe an innate behaviour not discussed in the film. Why is it adaptive to havethis as an innate, as opposed to a learned mechanism?

In moths, and most flying insects, there is an innate mechanism called the dorsal light

reaction. Moths will fly at a 90 angle to a light source to ensure that the light is directly

above them. The importance for it is it orients the moth to be parallel to the ground.It is adaptive to have it as an innate mechanism because the moth needs to be equipped

from birth to be able to avoid and locate stimulus in order to survive and also to avoid

flying upside down.

5. Describe a learned behaviour not discussed in the film. Why is it adaptive to havethis as a learned as opposed to an innate mechanism?

Imprinting is a learned behaviour that is exhibited by many species, but for the most part

in birds. Imprinting is when a chick hatches, and in a short amount of time, socially

bonds to the first moving object it sees.

Imprinting is important as a learned behaviour because it allows the animal to engage in a

specific identity that includes who their mother is as well as what it prefers in a mate.

Imprinting would not be as beneficial as an innate behaviour because it wouldnt allow

for change in preference or identity. If the animal comes pre-programmed with all of the

aspects of identity it wouldnt be changing with the environment, an essential ingredient

in evolution.