Exam Notes - Questions

Question 1

How does the principle of allocation apply to the transgenic super mice example?

Answer 1

• doubling the growth of the mice reduced resources to other features
• mice ate less, stopped reproducing, slept more, caught more diseases, and didn’t live as long

Question 2

What trend do we see in a populations of high density?

Answer 2

• natural selection favours adaptations that enhance survival and reproduction with few resources

Question 3

What trend do we see in populations of low density?

Answer 3

• natural selection favous adaptations that enhance rapid and elevated rates of reproduction

Question 4

What kinds of growth pyramid can be seen in a population?

Answer 4

• rapid growth
• slow growth
• zero growth/decrease

Question 5

Why do the Cthamalus barnacles have a different fundamental niche and realized niche?

Answer 5

• they are outcompeted by the balanus barnacles
• they are forced to the very top of the rock face (aka the top of their fundamental niche), because the balanus can’t live there

Question 6

What is an example of Batesian Mimicry?

Answer 6

• wasp beetles mimicing wasp colouring to seem more dangerous than they really are

Question 7

What is an example of an inducible defence?

Answer 7

• mussels allocate more resources to shell strength and attachment to rock faces when there are predators around

Question 8

What happens when a keystone predators is removed from it’s ecosystem?

Answer 8

• the organisms that used to be prey for the predator grow in abundance
• this organism may outcompete other organisms in the area and reduce the biodiversity

Question 9

What did Sousa test in his rock experiment? What were his findings?

Answer 9

• how disturbances affect an environment
• specifically how disturbances to a rock affect the intertidal plants and animals who affix to that rock
• found that intermediate amounts of disturbance had the greatest biodiversity over rarely disturbed rocks and often disturbed rocks (intermediate disturbance hypothesis)

Question 10

Why is the idea of a climax community flawed?

Answer 10

• no area is truly stable, there will always be some amount of disturbance
• mature communities are more complex and always changing

Question 11

What features that affect population might be found on a bigger, closer island over a smaller, farther island?

Answer 11

• higher immigration
• shorter distance for colonizers to travel
• lower extinction
• more resources
• more diverse habitat to be partitioned

Question 12

What are some negative impacts that humans have on the ecosystem?

Answer 12

• oil spills
• industries
• poor logging practices

Question 13

Who was Rachel Carson?

Answer 13

• journalist, advocate for biologist
• wrote “Silent Spring”
• exposed effects of DDT on the environment and helped get it banned in North America

Question 14

What are some indicators that we have overshot the Earth’s carrying capacity?

Answer 14

• decrease in vital ecosystems
• decrease in non-renewable resources
• ozone depletion
• climate change
• biodiversity loss
• deforestation
• fisheries collapse

Question 15

What are similarities and differences between the expansionist perspective and the steady-state perspective?

Answer 15

• they both focus on a growing economy as something that is good
• expansionist sees the environment as being infinite, steady-state sees the environment as finite
• expansionist dumps waste, steady-state recycles

Question 16

What are the goals of conservation biology?

Answer 16

• to offset the biodiversity crisis
• to preserve indivudual species
• to sustain ecosystems
• to maintain genetic variability

Question 17

What often happens to small populations?

Answer 17

• small populations lead to inbreeding and random genetic drift
• leads to loss of genetic variability
• reduces individual fitness and population adaptability
• leads to lower reproduction and higher mortality
• leads to an even smaller population

Question 18

What are some values of biodiversity?

Answer 18

• resources
• commercial value
• recreational and aesthetic value
• scientific value
• self-preservation
• intrinsic value

Question 19

What are the causes of extinction?

Answer 19

• habitat destruction
• habitat fragmentation
• introduction of exotic species
• overexploitation of resources
• disruption of food chains
• pollution
• global warming

Question 20

What did various researchers find on easter island?

Answer 20

• Flenley and King: used that pollen samples to discover that there was less palm tree pollen at the time that settlers arrived
• Steadman: island fauna had changed
• Diamond: discovered that the settlers caused deforestation, which led to soil erosion and a lack of trees for fishing canoes

Question 21

What were some lessons learned from the Tragedy of the Commons?

Answer 21

• overuse and exploitation of the natural vegetation by having so many cattle caused soil erosion when it rained

Question 22

What are some obstacles with commons?

Answer 22

• they are difficult to protect since there is no direct owner
• no one wants to assist with costs
• resources are not monitored effectively

Question 23

What are some of the goals for wild life corridors?

Answer 23

• allow for recolonization
• allows for gene flow
• introduces new alleles that would possibly counteract deleterious effects of inbreeding or genetic drift

Question 24

What is one example of a sustainable operation?

Answer 24

• collin’s pine company
• family-owned logging company
• tree planting and selective logging allow them to continuously replenish their resources

Question 25

What may happen when the world’s population reaches 8 billion in the next 2 decades if we haven’t found a solution to sustainability?

Answer 25

• more wars over the commons

- social justice issues