Ch 26+ Flashcards
(96 cards)
1
Q
Many organisms use the same environments and ____ are often limited.
A
resources
2
Q
Ecology
A
the study of interactions of organisms with one another and their environment
3
Q
Community
A
all species that occur in a given area
4
Q
______ have characteristics that populations and species do not have.
A
communities
5
Q
What are some characteristics of communities?
A
- energy flow, nutrient cycling, species turnover
- can be vague and quite difficult to quantify
6
Q
Assemblage
A
group of (potentially) interacting organisms in a community
7
Q
Guilds
A
set of species that use resources in a similar manner; deals with how they use resources
8
Q
A kingsnake, red-tail hawk, and the red-fox can be considered a _____ based on what they eat.
A
guild
9
Q
Species richness
A
the number of species in a given agea
10
Q
How is species richness determined?
A
intensive and long-term sampling
11
Q
Major determinants for species richness and abundance
A
- latitude and elevation
- environmental factors
- time
12
Q
____ and ____ are major determinants in biodiversity
A
latitude and elevation
13
Q
Latitudinal species gradient
A
-species richness increases from the poles to the tropics
14
Q
Habitats with greater ___ and ____ complexity tend to have more species.
A
spatial and structural
15
Q
Intermediate disturbance hypothesis
A
The basic idea is that some disturbance in an ecosystem continually disrupts interspecific competition. If you leave an ecosystem alone, things become specified.
16
Q
How are assemblages determined?
A
by interactions at different levels
17
Q
Assemblages determined by individual organisms:
A
competition, predation, parasitism
18
Q
Assemblages determined by population processes
A
- density-dependent
- reciprocal negative density dependence
19
Q
Reciprocal negative density dependence
A
one population keeps the other one down
20
Q
Density-dependent processes
A
the size you have determines what you experience. ex. sickness
21
Q
3 main results of competition
A
- resource partitioning
- habitat/geographic displacement of species
- morphological differentiation of sympatric species
22
Q
Resource partitioning
A
differential use of resources by species in an assemblage
23
Q
Competitive exclusion principle
A
no two species can occupy the same niche indefinitely
24
Q
Competition is stronger between
A
ecologically more similar species
25
In the case of anoles, when can the small A. wattsi successfully compete with the larger A. gingivinus?
when parasite reduces competitive ability of A. gingivinus (the big anole)
26
Example of Morphological differentiation of sympatric species
character displacement
27
Types of character displacement
- convergent
| - divergent
28
Character displacement= convergent
| Frog example
- different release calls when isolated
| - similar release calls when sympatric
29
Character displacement= divergent
| frog example
- similar advertisement calls when isolated
| - different advertisement calls when sympatric
30
_______ and _________ can effectively result in resource partitioning.
phenotypic plasticity; character displacement
31
Phenotypic plasticity and character displacement can effectively result in _________.
resource partitioning
32
When both Spea tadpole species occurs, the S. multiplicata becomes less carnivorous and S. bombifrons becomes more carnivorous. What does this show?
character displacement
33
Predation
one organism killing and eating another
34
parasitism
one organism feeds on another in a way that is non-lethal (at least in short term)
35
Predation and parasitism depends on:
density of prey and hosts
36
Predation and parasitism can interact with ______
competition; ex. predator can reduce density of prey to the point where competition among prey individuals is reduced
37
Predation and parasitism can affect ____ _____
resource partitioning; ex. presence of predators can reduce activity of prey
38
Phylogenetic relationships and evolutionary history affect _____.
ecology; hard to determine evolutionary cause of lineage diversity
39
Phylogenetic inertia
the limitations on the future evolutionary pathways that have been imposed by previous adaptations. "You are what you are because of the genes your ancestors gave you"
40
Ecomorphs
species of different phyletic origin with similar morphological adaptations to similar niches; ex. anoles on different islands
41
___ ____ is an example of a new analytical tool becoming important to ecology.
niche modeling
42
niche modeling
- uses distribution and environmental data to generate models of environmental features that should be associated with a species niche
- identifies possible distributions associated with predicted changes in climate, diet, habitat alteration, etc.
43
What are some of the major factors affecting communities and assemblages?
- latitude and elevation
- temperature and humidity
- competition
- predation and parasitism
- physiological tolerances
- phylogenetic history
44
The importance of the major factors affecting communities and assemblages depends on
the kinds of organisms involved, nature of the environment, and interactions
45
Biogeography
study of past and present distributions of organisms
46
_____ history strongly affected the evolution and distribution of organisms
earth
47
Equilibrium Theory of Island Biogeography
- # of species on an island reflects balance of colonization and extinction
- rates of colonization and extinction depend largely on island size and distance from mainland
- so island size and distance affect # of species present
48
The theory of island biogeography combines what two common patterns in nature?
species-area relationship
| species-isolation relationships
49
Species-area relationship
as area increases, so does species richness (levels off eventually)
50
species-isolation relationships
the greater the distance form the mainland, the lower the number of species that arrive at a new location
51
Ecological biogeography
early studies of ecological determinants of distributions; emphasizes recent correlates of current distributions
52
Historical biogeography
integration of Earth history and phylogenetic relationships with ecological biogeography
53
Consideration of _____ critical for recognizing historical effects in addition to recent ecological effects
phylogenetics
54
niche conservatism
closely related species maintaining ecologically similar traits
55
niche evolution
divergence in ecological traits; "use something new"
56
Endemism
restriction of species to a particular area
57
Disjunct populations
occurrence in different areas with gaps in between
58
Vicariance
fragmentation of ancestral distribution by formation of geographic barriers
59
Dispersal
migration of organisms across pre-exisiting barriers
60
Area cladogram
phylogeny diagram of areas
61
Assumptions of vicariance
- biotas geographically static
- geological events create barriers
- biotas diverge after separation by barriers
62
Dispersal Theory
- lineages have a center of origin
| - lineages disperse from center of origin across barriers
63
Dispersal is common within ______ . Dispersal to ___ infrequent, but known to occur.
land masses; islands
64
_____ are responsible for many dispersal events
humans
65
Correspondence between distributions and phylogenetic divergences indicate _______.
vicariances
66
Many kinds of barriers can result in vicariance:
continents, mountains, rivers, ecological transitions, etc.
67
Phylogeography
the study of the historical processes that may be responsible for the contemporary geographic distributions of individuals
68
Historical biogeography and phylogeography founded on principle that:
Earth and life evolved together
69
Conservation Biology
a synthetic discipline addressing the dynamics and problems of perturbed species, communities, and ecosystems.
70
Managing endangered species, addressing effects of human influence on populations, and habitat restoration are all aspects of:
conservation biology
71
Why has conservation biology not been very successful?
- governments view growth as positive (human population)
- unsustainable resource use (using it fast)
- global climate change
72
Major focus of conservation biology is the maintenance and preservation of _______.
biodiversity
73
Biodiversity
variety of living organisms at all levels of organization and the variety of habitats and ecosystems (and processes therein)
74
3 common measures of Biodiversity:
- ecosystem
- genetic
- species
75
Genetic diversity
the gene pool of a population
76
Alpha diversity
number of species in a community or habitat
77
Beta diversity
difference/change in species number along an environmental gradient
78
Gamma diversity
difference/change in species composition among similar habitats in different areas
79
Community/Ecosystem Diversity
number of species associations or communities throughout an entire naturally occurring or artificially defined gradient
80
Extinction
the permanent loss of a species (or gene, or lineage)
81
Background extinction rate
the number of species appearing is slightly higher than the number disappearing
82
Effects of habitat loss
- direct effect
| - edge effect
83
Direct effect
species disappear from area (effects extend beyond the edges of lost habitat)
84
Edge effect
changes in community structures hat occur at the boundary of two ore more habitats
85
Effects of pollution are not always obvious. When does action occur?
action is rarely preventative, usually occurs with an impending crisis or in the midst of one.
86
Atrazine
- chemical contaminant
- compelling evidence of hormonal interruptions in amphibians
- EPA allows 3.0 ppb in drinking water
- effects studied in frogs by Tyrone Hayes
87
Environmental acidification (acid rain)
- arises from the combustion of fossil fuels and the release of Sulfur and Nitrogen Oxides into the air
- reacts with moisture to produce sulfuric acid and nitric acids and are returned to earth by snow or rainfall
88
Ecoestrogens
estrogen-mimicking chemicals produced by plants and fungi (defense compounds)
89
Fibropapillomatosis
-tissue-proliferation legions that interferes with organ function and reduces ability of turtles to escape enemies and find food
90
Overexploitation
Tragedy of the commons: when multiple individuals act in their own self-interest contrary to the common good, resources will be overexploited
91
Wildlife harvesting
legal or illegal capture of wildlife for human use
92
Sustainable use
allows the limited harvest of a population, providing that the portion of the population remaining is able to reduce and maintain itself
93
Fate of sustainable use programs depnds on:
how accurately biologists can assess reproductive potential and demography of each population in order to accurately track number captured
94
What has been an effective management tool for hunted populations when special interests do not override the recommendations of the biologists?
quotas
95
Exotic species
species that are non-native and introduced (intentionally or not)
96
Issues with exotic species
- can have very detrimental effects on native flora and fauna
- often accompany human habitat alteration, separating effects of each can be quite difficult
- bring their own diseases with them
- local populations have not evolved alongside these diseases
