Species Interaction

Question 1

tropic interactions

Answer 1

involve feeding
benefit one species at the expense of another (+/-)
predation (predator, prey)
herbivory (plant, animal)
parasitism (parasite, host)

Question 2

avoidance mechanisms

Answer 2

• employed by prey
• crypsis (camouflage, mimicry)
• non-cryptic defenses (chemical defenses, armor/weaponry, warning signals, mimicry)
• behavioral defenses (alarm calls, threat displays, group behavior)

Question 3

cryptic defenses

Answer 3

• involve deception
• camouflage: blending into or looking like your background habitat
• mimicry: looking like something else
• employed by predator and prey
  ex: pattern of Eudryas moth looks like bird droppings

Question 4

non-cryptic defenses

Answer 4

noxious or harmful to the predator in some way
chemical: smelly, distasteful, confusing, toxic
mechanical: spikes, spines, teeth, claws, armor

Question 5

aposematic signals

Answer 5

• aka presence of aposematism
• bright colors or patterns that warn predators of toxicity
• avoided cost: getting eaten in the first place since there is a signal that prevents it from happening

Question 6

Batesian mimicry

Answer 6

• some organisms skip the defense and rely on the warning
• rely on the fact that there are others in the community with the same aposematic signal and an actual defense
  relies on sensitization - predators begin to associate a visual stimulus with a noxious defense

Question 7

Mullerian mimicry

Answer 7

• species that look the same (share the same aposematism) and have a defense mechanism to back the signal up
• beneficial to both species since they predators will associate the visual stimulus with both prey

Question 8

behavioral defenses

Answer 8

warning call: alerts others of your own species to the presence of danger
threat display: makes you look more intimidating to predators
schooling and herding: an individual is less likely to be captured

Question 9

herbivory defense mechanisms

Answer 9

plants also have avoidance mechanisms
chemical defenses, spines/thick bark

Question 10

herbivore adaptations

Answer 10

have adaptations to get around plants’ defenses
tolerance of chemicals, tough teeth/mouth, behavioral adaptations

Question 11

coevolution

Answer 11

many predator and prey relationships evolve together in order to adapt to each other
giraffes grew tougher mouths due to the thorns that evolved due to giraffes

Question 12

parasites

Answer 12

eat their hosts without killing the hosts
mortality depends on the extent of the infection

Question 13

endoparasites

Answer 13

live inside the host
macro: different types of worms and flukes
micro: bacteria, viruses, and fungi that we refer to as pathogens

Question 14

ectoparasites

Answer 14

feed from outside the host
macro: ticks, fleas, mosquiotes
micro: fungi, viruses, bacteria

Question 15

predator-prey interactions

Answer 15

shape ecosystems
ex: otter predation keeps sea urchin populations under control, which helps to keep the kelp population stable and present

Question 16

otter-kelp interaction

Answer 16

indirect interaction
the presence of otters increases the presence of the kelp because the otters keep the population of sea urchins in check

Question 17

diversity/evolution of traits

Answer 17

is a result of trophic interactions
shape phenotypes and ecosystems

Question 18

competition

Answer 18

-/0 or -/- interaction
competitive exclusion (0/-)
competitive coexistence (-/-)

Question 19

competition occurs when

Answer 19

species both want to use a limiting resource
takes place over a limiting resource: food, space, light - every resource has a carrying capacity and affects the carrying capacity of other animals

Question 20

interference competition

Answer 20

actively preventing the other species from accessing a resource by displaying agonistic or territorial behavior

Question 21

exploitation competition

Answer 21

more efficient user of the resource

Question 22

tree competition

Answer 22

when competing populations live in the same habitat, both populations are negatively affected
early in succession, tree species that grow fast and need a lot of sun are the most common. As the forest gets thicker, these species lose out to the other tree species that are more tolerant of shade

Question 23

competitive exclusion

Answer 23

species is prevented from occupying a habitat by its competitor, but the competitor is not affected
0/-

Question 24

competitive coexistence

Answer 24

each of the coexisting species stays in the habitat but both populations have a lower carrying capacity

Question 25

resource partitioning

Answer 25

evolutionary pattern that helps potentially competing species avoif competition takes place when competing species use different parts of a limiting resource character displacement occurs as phenotypes evolve to fit those niches ex: Galapagos finches *competitive coexistence*

Question 26

fugitive species

Answer 26

species selectively leaves habitat when a major competitor is present ex: cheetahs abandon their grounds when lions are near since they know they cannot compete

Question 27

realized niche

Answer 27

spaces and resources in a habitat that a species actually uses when coexisting with a competitor often smaller than fundamental niche

Question 28

fundamental niche

Answer 28

spaces and resources in a habitat that a species would use under ideal circumstances tested via removal experiments

Question 29

positive interactions

Answer 29

benefit one or both species commensalism (0/+) mutualism (+/+)

Question 30

commensal interactions

Answer 30

positive for one species and neutral for the other ex: Pilotfish and sharks ex: frogs and tree bark

Question 31

true commensalism

Answer 31

may be rare barnacles on a whale can benefit by having a good place to live and access to food and water dense clusters can cause skin irritation and eczema increase drag on whale

Question 32

mutualistic interactions

Answer 32

benefit both species aphids excrete sugary liquid called honeydew that ants find delicious and nutritious - in return, ants protect aphids by biting and spraying formic acid

Question 33

ants in bullhorn acacia trees

Answer 33

clear the ground around their tree, getting rid of competing plant species attack other insects that approach or other mammals that eat the leaves

Question 34

myrmecophytes

Answer 34

specialized structures to provide housing and food for ants hollow structures with doors provide a shelter for ants to build their nest Mullerian bodies are protein and sugar-rich and produced by plants to serve as animal foodin

Question 35

interaction outcomes

Answer 35

vary depending on how stressful the habitat is Iva and Juncus coexist in coastal habitats, but in some areas the interactio is competitive - they decrease each other's carrying capacity due to the limited nutrients available in the soil competition more common in less stressful environments since populations are limited by each other vs. abiotic factors

Question 36

outcomes in stressful environments

Answer 36

in other areas, the interaction is commensal - the presence of Juncus increases the success of Iva tends to occur where the soil is extra salty - Juncus thrives well in soil and its presence changes the habitat into a habitat where Iva can thrive plants do not grow enough to compete with each other *ecological facilitation*

Question 37

stressful environments

Answer 37

high altitude, frequent storms, unstable or poor soil, variable access to food