Community Ecology Flashcards
what is community ecology?
study of interspecific interactions
“inter”= between
organisms interacting with individuals of different species
what is symbiosis?
means that species interact/have direct contact with each other
how is symbiosis now defined?
+/-/0
what are the types of symbiosis? (6, but listed 7)
competition, predation, herbivory, parasitism, mutualism, commensalism
facilitation is not symbiosis
what is competition symbiosis?
different species compete for a resource that limits their growth and survival
-/-
what is predation symbiosis?
one species kills and eats another species (predator eats prey)
+/-
what is herbivory symbiosis?
an organism eats parts of a plant or algae
+/-
what is parasitism symbiosis?
one organism (the parasite) derives nutrients from another organism (the host) which is harmed in the process
+/-
what is mutualism symbiosis?
both species benefit from the interaction
+/+
what is commensalism symbiosis?
one species benefits, while the other species is neither helped nor harmed from the interaction
+/0
what is facilitation?
one species has a positive effect on the survival and reproduction of another species without living in direct contact
+/0 or +/+
what is an ecological niche?
is how an organism makes a living
its role in the environment
what happens when two species compete from limited resources in the same ecological niche?
one will be more efficient at gaining access to resources and drive the other out or to extinction
what is it called when a two species are put together and one out competes the other?
competitive exclusion principle
how can two species with similar niches coexist?
if resource partitioning occurs - division of environmental resources to reduce competition
how do anolis lizards live in close proximity in the Dominican Republic?
live on different perches/niches
how do differences come about between the species?
evolution
what class do lizards belong to?
reptiles
how do you know if an organism is an amphibian?
metamorphosis
what is a fundamental niche?
the niche an organism potentially uses
what is a realized niche?
the niche an organism actually uses
what organisms are pictured in this experiment?
two species of barnacles
when together, chthmalaus is usually found on higher rocks, and balamus on lower. what type of niche is this?
realized
what happened when balanus was removed?
chthamalus grew on both lower and higher rocks
fundamental niche
what is sympatric?
different populations located in the same geographic area
what is allopatric?
populations located in different geographic areas that do not that interact
what happened when finches live in different islands?
similar beaks
what happens when finches live on the same island?
they diverged their beak depths to feed on different sized seeds and reduce competition
what is character displacement?
the tendency for characteristics to diverge more in sympatric than in allopatric populations
what is cryptic coloration? ex
camouflage
enables an organism to blend into its surroundings
leaf insect, leafy sea dragon
what is aposematic coloration? ex
organisms with chemical defenses have bright warning coloration to warn predators they have toxins
poison dart frogs
how do poison dart frogs get their toxicity?
die of insects- ants, mites, etc
what do the larvae of monarch butterflies eat and store in their tissues that is toxic?
milkweeds
what are mechanical defenses? ex
defenses such as spikes or thorns
porcupines
can porcupines throw their quills?
no
what does grass contain in its cells that could deter a small insect from eating it?
SiO2- silica/silicon dioxide
crystals also found in sand and used to make glass
what are distasteful/harmful chemicals? ex
any sort of smell that deters predators
marigolds
why are marigolds often planted around gardens?
they contain a pungent odor that deters many insects, Deers, and rabbits
what milky substance do opium oppy seeds produce?
opiates- morphine
codeine - pain relief
narcotic- heroin
what is deceptive coloration? ex
moths have false eyes spots to make it look like a large predator (owls)
what is disruptive coloration? ex
type of camouflage such as stripes or spots that create an optical illusion to break up body outlines
zebra
are zebras black with white stripes or white with black stripes?
black with white stripes - embryological development shows that they are black in womb and white stripes come later in development
what is counter shading?
a type of camouflage with a dark dorsal side and lighter ventral side
why do animals have countershadowing?
underwater animals: viewed from above, black blends with darkness of water; viewed from below, white blends with surface sunlight
what is mimicry?
it is the similarity of one species to another
3 examples of mimicry
Batesian, Mullerian, Aggressive
what is batesian mimicry?
when a harmless or palatable species mimics a harmful or unpalatable species
ex. caterpillar of elephant hawkmoth mimics small poisonous snake
what is mullerian mimicry?
when two or more unpalatable/harmful species resemble each other so that predators quickly learn to avoid the group entirely
ex. bees, wasps, yellow jackets, hornets
ex. viceroy and monarch butterflies (viceroys taste worse)
what can bright colored warning patterns also be considered as?
aposematic coloration
what do adult monarchs eat?
nectar and water to drink
*only larvae eat milkweed
what is aggressive mimicry?
when a predator uses mimicry to catch prey
ex. anglerfish
what natural lure does a female anglerfish use to draw its prey closer?
light dangling above its mouth
how many males will a female anglerfish carry on her body?
6+
two types of parasitism
endoparasites - live within the body of their host (tapeworm)
ectoparasites- feed on the external surface of hosts (ticks)
how can a person get tapeworm?
eating undercooked meat
how long does it take after being bitten by a tick does it take for the bacteria to enter the host?
48 hrs
2 types of mutualism
obligate mutualism- one species cannot survive without its partner (bees and bee pollinated flowers)
facultative mutualism - where both species could survive alone (ants and acacia tree)
what lives inside intestines of termites that digests wood cellulose?
protists that contain bacteria that makes enzyme cellulase
what type of mutualism is termites and protists?
obligate
how do bees see the world?
yellow, blue, uv
what is coevolution?
bee gets nectar and pollen (protein) to feed young while inadvertently pollinating flower
what is species diversity? what is it made up of?
the variety of different kinds of organisms that make up a community
species richness and relative abundance
what is species richness?
the number of different species in a community
what is relative abundance?
how many of the different species
how does a community’s species diversity affect invasive speces?
the more diverse the community is, the less prone invasive species are to invading it
6 ways to name invasive species
invasive
non-indigenous
non-native
invader
exotic
introduced
what are some invasive species in michigan?
zebra mussels, quagga mussels, round goby, Asian carp, purple loose strife, phragmites, sea lampreys etc
what invasive songbird from the project conducted by American Acclimatization Society caused greatest impact on native bird species due to their aggressiveness?
European starlings
what climbing vine originally imported from Japan to control erosion is an invasive species across the SE US?
Kudzu
what invasive species was brought to Hawaii to control rats in the sugar cane and now is eating ground-nesting Hawaiian birds and their eggs?
mongoose
why do invasive species proliferate in new environments?
since they did not evolve in the new environment, there are often no predators or local diseases (viral or bacterial) that affect them and they often outcompete natuve species for resources
what is the trophic structure?
the feeding relationships between organisms
how does a food chain differ from a food web?
food chains are simpler; food webs show all possible feeing relationshios/are more complex
which was are the arrows pointing?
toward who is doing the eating
what are 1degree producers?
autotrophs “ self-feeders”
what are krills in the food web?
primary and secondary consumers
what is missing from these two images?
arrows pointing towards decomposers (fungi, bacteria)
are photosynthetic autotrophs always primary producers?
no, deep sea communities exist around hydrothermal vents in the oceans where light does not penetrate. therefore, the primary producers are chemosynthetic organisms that live off on inorganic chemicals such as hydrogen sulfide (H2S)
name some organisms living amongst the geothermically heated waters around black smoker vents?
giant tubeworms
ghost crabs
fish
bacteria
eel
how many levels do most food webs consist of?
5 or fewer
why do food webs consist of few levels? (3)
energetic hypothesis
dynamic stability hypothesis
large carnivores tend to be larger at successive trophic levels and most cannot live on small food items because it will not meet the metabolic needs
energetic hypothesis
inefficiency of energy transferred between levels
dynamic stability hypothesis
long food chains are less stable than short chains as an environmental shock can cause food supplies to reduce all the way up the food chain. the longer the food chain, the more apex predators will be affected
what percent of energy is transferred to primary producers to consumers? what percent if energy is lost between trophic levels?
10%
90%
in what form is energy lost as?
heat- lots are used for cellular processes (growth, division, movement, energy locked in the bonds of waste- egestion_
what is the rule that explains the concept of transferring energy between trophic levels?
the 10% rule
what animal is the largest to ever live and an exception to a large animal who does eat much smaller prey?
blue whales eat krill and plankton
what are dominant species?
the most abundant species in a community
why are elm trees not a dominant species anymore?
Dutch Elm Disease in fungi on beetles killed them
what are keystone species?
not dominant in a community, but exert a strong impact on community structure
example of keystone species?
nile perch was introduced to decrease cichilid population
two ways to say native?
endemic
indigenous
when sea otters are abundant, what happens to kelp and urchins?
urchins decrease
kelp increase
when seat otters decrease, what happens to kelp and urchins? keytsone species?
kelp decrease
urchins increase
otter keystone species
what are ecosystem engineers?
species that alter their environment
why do beavers create dams?
to create still deep waters to protect their family from predators
wood and bark is their food
how does a disturbance change a community?
by removing organisms or altering resources available
keep a community from reaching equilibrium
moderate levels of disturbance foster greater species diversity than high or low levels of disturbance because some niches become available for new species to enter while keeping some og species intact.
intermediate disturbance hypothesis
would you expect to have greater species diversity near a path in a forest or deeper in the forest?
near a path
what type of disturbance is fire considered?
high level disturbance
what biome is yellowstone?
confierous/boreal/taiga
what is ecological succession?
transition in the species composition following a disturbance
what type of successions are there?
primary and secondary
what is primary succession?
no fertile soil present initially
what situations lead to primary succession? (4)
new volcanic island forms
rubble left behind from a retreating glacier
on a sand dune
rocky bottom lack undergoes weathering
what are pioneer species in primary succession?
lichens, mosses, bacteria
when the pioneer community dies and decays they facilitate the appearance of later successional species by creating fertile soil for later successions. what is this soil called?
humus
what are oak trees in communties?
climax community
how long can it take primary succession to occur?
100s to 1000s of years
what two things make up a lichen?
fungus + photosynthetic partner (cyanobacteria or algae)
what type of symbiotic relationship do most lichen have?
mutualism
fungus provides water, nutrients, and a place to live; the photosynthetic partner provides sugar/food
if you see lichens growing on trees or rocks, what is this an indicator of?
good air quality
2º succesion
existing community is cleared by some disturbance that leaves soil intact
what situations lead to secondary successions?
after a forest fire, abandoned farmland, deforestation, sediment/soil bottom lake dries up
what are the pioneer species in 2º succesion?
first annual then perennial plants, grasses, weeds
which is faster paced? 1º or 2º
2º since soil is already there which also contains seeds
latitudinal gradients
lower latitudes have more species than higher latitudes
how many ant species in alaska? in brazil
7; 200+
why do leafcutter ants collect trees?
to farm a fungus that grows on the leaves that they eat - mutualistic relationship
species area curve
the larger a geographic area of a community the more species it has
what are island equilibrium models? who made them?
models for island species biodiversity
EO Wilson
what is the equilibrium number in island equilibrium models?
the balance between the new species immigrating and those on the island going extinct
which type of island will have the greatest species diversity? why? (5)
larger islands that are closer to the mainland;
large islands are easier for colonizers to land on
more resources
a larger gene pool
variety amongst organisms to more resistant to diseases
easier to access
corals have what living within them?
photosynthetic golden-brown algae - zooxanthellae
under stress, corals expel their algae and this causes them to turn white, what is this called?
coral bleaching
what are some causes of stress to coral reefs? (7)
high water temperature
low water temperature
high pathogen infections
low pH
high UV radiation
low food availability
low salinity
what human fishing practices is also killing the reefs?
ocean trawling - boats dragging weighted nets on the seafloor to capture seafood
zoonotic pathogens
pathogens transferred from animals to humans- can be through direct contact with an infected animal or through intermediate species called a vector
what zoonotic disease transmits the pathogen Plasmodium and uses mosquitos as its vector?
Malaria - believed to have originated in gorillas
which sex on mosquitos is seeking mammalilan blood>
females- need proteins and Fe to produce eggs
mosquitos find mammals?
organic substances - co2 and another chemical in human breath and sweat with a “meaty” odor called octenol
