Chapter 17 Species Interactions and Community Structure Flashcards
In food webs, a feeding relationship is represented as a(n) ______ connecting two ______.
line; organisms
In representing the communities in Caño Volcán, one approach used by Winemiller was to _______ the most rare species.
exclude
In defining “strong interactions” in food webs, Paine felt that the most important factor in defining community structure was the ______, but not the ______ of interactions.
degree of influence; energy flow
Species that have a substantial influence on community structure due to their high biomass are referred to as ______ species
foundation
True or false: Blue Tits feed on larvae of the moth, A. geminipuncta.
False
They feed on the galls formed by G. inclusa thus forming a species interaction.
Food webs are ______.
used to represent feeding relations within a community
Which of the following interactions are considered to be strong interactions in Tscharntke’s food web of a Phragmites community?
Phragmites–A. geminipuncta
Phragmites–G. inclusa
T. arundinis–C. caerulus
In representing the communities in Caño Volcán, one approach used by Winemiller was to _______ the weakest trophic links.
exclude
Indirect interactions between two species require ______ species.
an intermediate
The most influential trophic relationships in a food web are known as ______ interactions.
strong
In a commensal relationship between two species, one species is ______ while there is neither harm nor benefit to the other.
benefited
In the Martinsen et al. study, the sprouts growing from trees felled by beaver have leaves that are ______ nutritious for the beetles than those growing on mature trees.
more
Which of the following trophic interactions were observed in the Phragmites community studied by Tscharntke? Arrows indicate the direction of energy flow, for example, A → B, indicates that A is eaten by B.
fly (G. inclusa) —> Blue tits
Phragmites —> moth (A. geminipuncta)
Phragmites —> fly (G. inclusa)
Stem-boring by larvae of ______ are responsible for inducing Phragmites to produce side branches.
A. geminipuncta
In the following, simplified food chain, which pairs of species have indirect interactions? Sp. A —–> Sp. B —–> Sp. C —–> Sp. D
Sp. A and Sp. C
Sp. B and Sp. D
Apparent competition is a type of ______ interaction.
indirect
Which of the following represents the indirect commensalism observed by Martinsen et al.?
Beaver — cottonwood — beetle
The purpose of the control treatment, in the experiment by Orrock et al., was to ______.
account for disturbance effects
Consistent with their hypothesis about apparent competition between mustard and bunch grass, Orrock et al. found ______ did better when ______ were excluded.
bunch grass; rodents
Predators that keep prey populations below their carrying capacity and prevent competitive exclusion by one of these species are known as ______.
keystone species
Indirect interactions between two species require ______ species.
an intermediate
In the intertidal food web of Mukkaw Bay, a ______ is considered to be the top predator.
seastar
If two species are joined through apparent competition, that means that they have a common ______.
predator
In the intertidal food web of the Gulf of California there are a total of ______ predators in the system.
11
The purpose of the experiment by Orrock et al. was to test for apparent competition between ______ and ______.
mustard; bunch grass
As a result of their experiments, Orrock et al. proposed that the rodents use ______ for protective cover, feeding on the ______.
mustard; bunch grass
A keystone species would be considered to be a type of ______.
foundation species
Paine concluded that greater numbers of predators in an intertidal community produces increased ______, leading to an increase in ______ the community.
predation pressure; diversity of
In the intertidal food web of Mukkaw Bay, the number of prey species eaten by the seastar Pisaster is ______ the number of prey species eaten by the snail Thais.
greater than
In the intertidal food web of the Gulf of California, a ______ is considered to be the top level predator.
seastar
In his first research in Mukkaw Bay on the role of predators in community diversity, Paine ______ predators for the experimental treatment in his study areas.
removed
In the months immediately following the removal of starfish, the percent of space occupied by the barnacle Balanus ______.
increased