Bio Final: ECOLOGY: COMMUNITY STRUCTURE AND SPECIES INTERACTIONS Flashcards
Types of species
native and non-native/exotic/alien
native species
normally occurs in a particular ecosystem. Endemic: restricted to a specific locality
ex) giant sequia tree (largest) coast redwood tree (tallest) bristle cone pine (oldest)
non-native/exotic/alien species
introduced into ecosystem, usually by humans. Feral, global amphibian declines
feral
domestic species becoming wild, ex) goats, burros, dogs, cats, aust brushtail opossum in new zealand
global amphibian declines
asian longhorn beetle, new england trees (lumber, male, syrup, tourism)
indicator species (bioindicators)
species that serve as early warnings of damage to a community or ecosystem health (range of tolerance) Ex) amphibians, trout, birds, orchids, dung beetles
-macroinvertebrates
macroinvertebrates
aquatic invertebrates (insects, crustaceans, snails, worms)= their abundance and diversity have been used as an indicator of ecosystem health and of local biodiversity
Keystone species
role of species more important than abundance= structure and function of ecosystem.
-pollinators, decomposers, predators vs prey, dispersion of plant seeds, habitat modification and soil improvement
Pollinator (keystone)
insects/birds
decomposers (keystone)
fungi/bacteria/dung beetles
predator vs prey (keystone)
sea otter vs sea urchins
dispersion of plant seeds (keystone)
birds (phainopeple: mistletoe)/galapagos tortoise, ants
habitat modification (keystone)
elephants
soil improvement (keystone)
earthworms, burrowing mammals
types of species interactions
- symbiosis
- interspecific competition
- intraspecific competition
- predation
- parasitism
- mutualism
- commensalism
symbiosis
a close association between two different types of organisms in a ecosystem
interspecific competition
competition between different species for resources (food, space, sunlight, soil, water)
survival strategies for interspecific competition
1) migrate 2) shift habits or behavior= resource partitioning (ex. shorebirds bill size/shape) darwin finches (bill shape) dung beetles (dung type, size, odor, and spatial frequency, soils) 3) population decline 4) extinction
intraspecific competition
competition between the same species for resources and mates
predation
predator vs prey a) remaining prey have greater access to resources b) improves gene pool
“arms race”
predator strategies
1) mobility: pursuit (cheetah vs impala)
2) ambush: camoufaluge/ sit and wait (rattlesnake vs kangaroo rat
3) cooperation: work together as a group to capture prey (wolves, lions, dolphins, sea snakes, fish)
prey survival strategies
1) mobility= escape
2) protective covering (shells, thick bark, spines, quills)
3) chemical deterrent: poisonous, irritating (nettles, beetles), foul smell (skunk) bad taste (butterflies/host plant) 4) warning coloration (aposomatic): poison dart frogs, coral snake, skunk, butterflies (mimicry)
behavioral strategies
mimicry (caterpillar looks like snake, bird feces)
-mullerian and batesian
mullerian
when two or more poisonous species are prey for a predator and the similar color patterns are not attributed to being related
batesian
when a harmless species mimics the color pattern of a dangerous species
looks bigger (behavioral strategies)
spreading wings, puffing up
group protection (behavioral strategies)
schools of fish, herds of antelope, flocks of birds
behavior: play dead (behavioral strategies)
opossum, hognose snake
autonomy (behavioral strategies)
tail loss in lizards
aggressive (behavioral strategies)
luring (males towards females) fireflies (light flashing) katydid (sound imitation)
imitation (behavioral strategies)
zone tailed hawk resembles turkey vulture- breaks from formation to ambush prey
reproductive (behavioral strategies)
flower mimics female of insect species=male insect copulates with it, subordinate males mimic females and sneak into harem and mate
parasitism
one species (parasite) feeds on part of another organism (host). parasite benefits host is harmed (rarely killed); parasitic organism is usually smaller than the host. 3 million species of parasites
examples of parasitism
mistletoe, insect galls (oaks, creosote), tapeworms, arthropods (ticks, lice, fleas) protozoa (malaria, giardia) pinworm, roundworm, liver flukes
parasite
endoparasite: internal ectoparasite: external
brood parasitism
birds (cowbird, cuckoo)- lays eggs in nest of other bird (california gnatcatcher)
mutualism
species interactions where both species benefit
pollination (mutualism)
plants
nitrogen fixation (mutualism)
plant vs fungi: mycorrhizal fungi
protection (mutualism)
anemone vs clown fish
food supply (mutualism)
oxpecker bird vs giraffe, rhino, cape buffalo, pilot fish and sharks
lichens (mutualism)
-fungi and photosynthetic algae: corals and photosynthetic algae and yuccas and yucca moths (pollinator/larval food source) plant/mammal/fungi
plant/mammal/fungi [lichens (mutualism)]
forest trees depend on mycorrhizal fungi for efficient nutrient uptake, while the fungi rely on the tree for carbohydrates -mycorrhizal fungi also depend on fungi-consuming mammals (flying squirrels) for spore dispersal, which inoculated distant soil patches, disturbed sites and newly formed tree roots
commensalism
one species benefits the other is not harmed or helped (epiphytes: orchids, bromeliads) shade plants, cleaner fish (sharks, whales)
