Lecture 19- Food Webs III

Question 1

Community struture focuses on what two interactions?

Answer 1

1. Intraspecific interactions
2. Interspecific interactions

Question 2

What is intraspecific interactions?

Answer 2

Occur within a species and more related to behavior

Question 3

What is interspecific competition?

Answer 3

Occur between species and changes over time

Question 4

What is competition?

Answer 4

• (-/-)
• The interaction can be detremental to both species

Question 5

What is predation, herbivory and parasitism?

Answer 5

• (+/-)
• The interaction is beneficial to one but detrimental to the other

Question 6

What is mutalism?

Answer 6

• (+/+)
• The interaction is beneficial to both species

Question 7

What is commensalism?

Answer 7

• (+/0)
• The interaction is beneficial to one species and the other species is unaffected by it

Question 8

What is an autotroph?

Answer 8

• Self nourished
• Organisms that assimilate energy from either sunlight (green plants) or inorganic compounds

Question 9

What is a heterotroph?

Answer 9

• Nourished by others
• Organisms that use organic materials as a source of energy and nutrients

Question 10

What does a photoautotroph do?

Answer 10

Aquires energy from sunlight

Question 11

What is an example of a photoautotroph?

Answer 11

Plant, algae, biocrusts

Question 12

What does a chemoautotroph do?

Answer 12

Acquires energy from oxidation of hydrogen, sulfide, methane, ammonia

Question 13

What are some examples of chemoautotrophs?

Answer 13

Prokaryotes, bacteria

Question 14

What is a herbivore?

Answer 14

An organism that consumes living plants or their parts

Question 15

What is a carnivore?

Answer 15

An organism that kills and eats other organisms or parts of it

Question 16

What is an omnivore?

Answer 16

An organism with a broad diet that feeds on more than one trophic level

Question 17

How do we create a food web?

Answer 17

• Direct observation of feeding behaviours (remains of prey, trail cameras)
• Dietary analysis (scat analysis, stable isotope analysis)

Question 18

Why would you use a predator as a ecosystem indicator?

Answer 18

• Apex predator are long-lived and wide range
• Dietary habitats represent prey population dynamics
• Changes in prey availability affect abundance, distribution and changes in lower trophic levels

Question 19

Scat analysis allows for?

Answer 19

• Allows for high sample size
• Can collect over broad temporal and spatial ranges

Question 20

What are some drawbacks of scat analysis?

Answer 20

• Biased towards large, hard bodied prey
• May be hard to find
• Cannot trace back to individual behaviours

Question 21

What happens in carnivore scat analysis?

Answer 21

• Dissection of scat to identify hair and bone fragments
• Can use eDNA to determine species preyed on

Question 22

What happens in herbivore scat analysis?

Answer 22

Based on eDNA of plants in scat

Question 23

Tissue analysis allows for?

Answer 23

Allows for analysis of diet over time

Question 24

Tissue analysis can be determined by?

Answer 24

• Hair
• Nails
• Fat
• Blood

Question 25

What are the two types of tissue analysis?

Answer 25

* Fatty acid signature analysis * Stable isotope analysis

Question 26

What is fatty acid signature analysis?

Answer 26

* Analyze lipid signitures of prey species * Long chain fatty acids remain largely unchanged through trophic levels (absorbed and deposited in predator tissue)

Question 27

Describe the process of fatty acid signature analysis

Answer 27

* What is the preys fatty acid signiture? Confirm whether they're distinct * What combinations of prey would result in the fatty acid signature of the predator?

Question 28

Stable isotope analysis can be done through the collection of?

Answer 28

Blood, tissue, hair

Question 29

An omnivore diet analysis can be done with what analysis?

Answer 29

Stable isotope analysis to show specialized diet between individuals

Question 30

What are the groups of isotopes used in stable isotope analysis?

Answer 30

* 12C and 13C * 14N and 15N * 13C and 15N