One More Ecology Deck!

Question 1

What is the difference between dispersal and migration?

Answer 1

• dispersals the movement between subpopulations (connects metapopulation which is many small interconnected groups)
• migration is the actual movement of an entire population to a new geographic region

Question 2

What does behaviour do in the ecosystem?

Answer 2

• mediates interactions between organisms and their environment

Question 3

How may have altruism arisen?

Answer 3

group selection

Question 4

How may have eusociality arisen?

Answer 4

• kin selection or ecological constraints

Question 5

Why do plants have such widespread chemical and physical defences?

Answer 5

• plants face a lot of strong selective pressures from herbivores
• evidence by non-native species coming an plants having virtually no defence

Question 6

What are the consumptive and non consumptive effects of predators?

Answer 6

• consumptive: direct, eats the prey, but only a fraction of prey is consumed
• non-consumptive: indirect effects, changes to prey physiology, behaviour and morphology without even harming them ; cortisol levels increased in peak predator years, and limited reproductive success

SO: predators limit populations by increasing per capita death rate and decreasing per capita birth rate

Question 7

what is a disclimax community?

Answer 7

• the dominant community that persist only from repeated disturbance (others are cleared, so they get to remain)

Question 8

Describe the climax community of inhibition succession models?

Answer 8

• long living species that are resistant to biological and -physical disturbance
  persist because they made environment unsuitable for all else

Question 9

Why is the Shannon index important?

Answer 9

• important to ecologists who study rare species and their importance to their community

Question 10

What is an example that demonstrates increased environmental complexity leads to increased diversity?

Answer 10

• warbler species increase as tree foliage increased
  or
• cyclotella and arionella both persists when nutrients are limiting (phosphorus or silicate) - indicates coexistence but also environmental heterogeneity

Question 11

Describe the species response to prairie dog disturbance?

Answer 11

• disturbance in grasslands allows for good competitors and good colonizers to persist BUT shrub diversity is invariant while the grass diversity changes
• indicates that different species with different tolerance and life histories may respond differently to disturbance

Question 12

Did the intermediate theory hold true? Why?

Answer 12

• only occurred in 20% of cases, some no relationship, some even had a negative relationship
• relationship between disturbance and diversity is complex
• likely the case because of stability : resistance and resilience
• in park grass experiment different levels of disturbance showed that while groups did not vary individual species did –> stability is determined by the overall group, which is why diversity is important; ensures the chances that some species will be tolerant to disturbance - overall stability is determined by the combined performances of species, and overall response of a community is therefore not determined by the same species every year

Question 13

What is found in the taiga?

Answer 13

• bogs scattered throughout

Question 14

What do the grasslands support?

Answer 14

• herbivorous animals and insects
• large herds of grazers!

Question 15

Where can deserts be found geographically?

Answer 15

• deep in the continent or in the rain shadow of mountains

Question 16

What is oceanic circulation?

Answer 16

Driven by the wind, regulates earth’s climate

Question 17

How much light is absorbed in the ocean?

Answer 17

• 8% absorbed within first 10 m, little if any gets beyond 600m

Question 18

What is the salinity of the ocean land transition?

Answer 18

salinity is often variable, based on rate of evaporation and precipitation, and tide
- often salinity is vertically and horizontally stratified

Question 19

What is denitrification?

Answer 19

• energy yielding process that converts NO3 back into N2 gas under anaerobic conditions

Question 20

What does the combustion of fossil fuels contribute to nitrogen pollution?

Answer 20

• nitrous monoxides create photochemical smog and acid rain

Question 21

What is the relationship between distance to the beaver lodge and the exploitation levels?

Answer 21

• close to shore is more exploited, decreased richness

Question 22

What does increased phosphorus do in aquatic ecosystems?

Answer 22

• increases NPP and algal biomass but too much may lead to eutrophication

Question 23

What is the most productive ecosystem?

Answer 23

• forests! (rainforests less productive than temperate forests because of the poor soil quality of rain forest)