Final Exam Short Answer Unit 5

Question 1

describe the following with a +, -, or 0. Competition, parasitism, predation, commensalism, and mutualism

Answer 1

• competition:(— ,—) ex: lions and hyenas
• parasitism: (+, —) ex: bacterial infection like tape worms
• predation: (+,—) ex: lion hunting zebras
• commensalism: (+, 0) ex: thing growing off a tree
• mutualism: (+, +) ex: mycorrhizae

Question 2

What are the advantages and disadvantages of sexual reproduction?

Answer 2

• Advantage, genetic variation-changing environmental condition.
• Disadvantage, sperm has to find the egg (fewer offspring produced), more components needed (cost of resources and energy), need to find a mate, half of offspring are males who don’t produce offspring by themselves, favorable genetics might not be passed down

Question 3

Compare ultimate and proximate causation. Give an example of each.

Answer 3

• Ultimate, fitness mechanisms (why). - Proximate, is how.
  Proximate: The muscles move (etc.)
  Ultimate: Bird egg rolls out of the nest but the mother puts it back. Sense that helps to increase survival rate and fitness.
  The ultimate level of causation refers to the behavior’s evolutionary significance; how the behavior enhances reproductive fitness. female animals often display preferences among male display traits, such as song.
  An ultimate explanation based on sexual selection states that females who display preferences have more vigorous or more attractive male offspring.
  The proximate cause refers to the immediate cause of a behavior, whether that be hormonal, neurological, cognitive, interpersonal, or cultural. a female animal chooses to mate with a particular male during a mate choice trial.
  A possible proximate explanation states that one male produced a more intense signal, leading to elevated hormone levels in the female producing copulatory behavior.

Question 4

Draw and explain the three types of survivorship curves.

Answer 4

• Type I (high survival rate for all of the life, but slow reproduction rate. Survival old, humans) curves depict individuals that have a high probability of surviving to adulthood.
• Type II (equal chance of dying through entire life) curves depict individuals whose chance of survival is independent of age.
• Type III (low survival chance for youth, but after youth, high survival chance. High infant mortality, but after that you probably live whole life) curves depict individuals that mostly die in the early stages of their life.

Question 5

How was the current mass extinction different from the previous five

Answer 5

• It is happening at a much higher rate due to human activities.
• mostly through the unsustainable use of land, water and energy use, and climate change.