pyramids & species
DESCRIPTION
Pyramids & Species. Three hundred trout are needed to support one man for a year. The trout, in turn, must consume 90,000 frogs, that must consume 27 million grasshoppers that live off of 1,000 tons of grass. -- G. Tyler Miller, Jr., American Chemist (1971). - PowerPoint PPT PresentationTRANSCRIPT
Three hundred trout are needed to support one man for a year.
The trout, in turn, must consume 90,000 frogs, that must consume 27 million
grasshoppers that live off of 1,000 tons of grass.
-- G. Tyler Miller, Jr., American Chemist (1971)
2.1.4 Pyramids in Ecosystems
2.1.5 How Pyramid Structure Affects Ecosystems
Pyramids
Graphical models of the quantitative differences between trophic levels of a single ecosystem
Usually Pyramids become narrower toward the top
http://www.geog.ouc.bc.ca/physgeog/contents/9o.html
Pyramids of Numbers
Number of individuals at each trophic level.
If the size of an organism is small, more can be present.
I.e.: ten mice in place of one rabbit.
http://www.biology.com/kimball/kimball.html?maincontent=F/FoodChains.html
Pyramids of Numbers - Variations A shows a typical pyramid of numbers
for carnivores; B shows the effect of a single large
producer such as a tree; C shows a typical parasite food chain
Blue birds
Pyramids of Biomass
Represents the standing stock of each trophic level
Measured in g of biomass per square meter
g/m2
http://www.biology.com/kimball/kimball.html?maincontent=F/FoodChains.html
Pyramids of Biomass more information -
consider total mass of organisms
almost always pyramid shaped, if a trophic level
gains all mass from the level below,
cannot have more mass than that lower level ( cannot weigh more than you eat).
The "missing" mass, that not eaten, becomes detritus and is decomposed. http://cr.middlebury.edu/es/altenergylife/biomass%20logo.gif
Inverted Pyramids
Occurs in BOTH pyramids of numbers and biomass
Occurs more often with numbers
Can also result from seasonal fluctuations, weather and natural disasters (biomass).
Pyramids of Energy
Show flow of energy through a trophic level (or the rate at which stock is generated)
90% of energy is lost at each transfer.
Conversion efficiency: ratio of net production at one level to to that of the next.
http://www.biology.com/kimball/kimball.html?maincontent=F/FoodChains.html
Pyramids of Energy: Loss?
Only 10% energy incorporated into biomass, the remaining 90% is lost as:1) feces2) used in respiration and lost as heat3) lost in urine
http://www.buildingenergyireland.ie/classified/beriheatloss1_lg.jpg
How does the Pyramid Structure Affect Ecosystems?
Typical Pyramid higher trophic
levels have less total biomass than those below
less energy is available
lower level sets the limit at the next level
Pyramid of energy - takes into account the turnover rate of the organisms, and can never be inverted.
http://i.pbase.com/o5/05/621605/1/67425663.LXLjH2og.IMG_1071.JPG
Ecosystem Function & Pyramids "bottom-up"
control - nutrient supply to the primary producers
"top-down" controls - predation and grazing by higher trophic levels
Pyramid Structure & Function?What type of controls do these exert
on food chains? Concentration of non-biodegradable
toxins? Limited length of food chains? Vulnerability of Top Carnivoes?
www.facstaff.bucknell.edu/ abrahmsn/bi356/
Species
A group of organisms that interbreed and produce fertile offspring.
Physical, chemical, or behavioral differences limit breeding between species
www.ramsar.org/ photo_species1.htm
Population
A group of organisms of the same species
living in the same area at the same time, and
which are capable of interbreeding.
sunsite.tus.ac.jp/multimed/ pics/animals/wolves-07.gif
Community
A group of populations living and interacting with each other in a common habitat.
www.aipress.com/pictureawards/ 28976-10.Catapillar.jpg www.bham-bot-gdns.demon.co.uk/ other.html
www.archbold-station.org/.../ unit4/unit4intro.html
Niche
A species' share of a habitat and the resources in it. ecological niche - depends on
where it lives AND what it does.
fundamental niche - the part of the habitat in which a species can live in the absence of competitors and predators
realized niche - the part it actually occupies is its.)
Habitat
The environment in which a species normally lives.
Example- woods, desert, swamp
www.ebibleteacher.com/ images/swamp.jpg
Ecosystem
A community of interdependent organisms and the physical environment they inhabit
http://blackhawkhomesteadnurscom.nxg.superpageshosting.com/ecosystem.jpg
Biome
A collection of ecosystems sharing similar climatic conditions, eg tundra, tropical rainforest, desert.
http://www.donnalatham.com/images/Biomes_Cvr.jpg
References
http://www.angelfire.com/sk/monkeypuzzle/index.html
http://martin.parasitology.mcgill.ca/jimspage/biol/intro.htm
http://www.schools.lth5.k12.il.us/bths-e/cowbird.html
Environmental Science, Toward a Sustainable Future Eight Edition by Richard T. Wright and Bernard J. Nebel
http://www.stanfordalumni.org/birdsite/text/essays/Disease_and_Parasitism.html
The May Fly
Species - Giant May Fly - (Hexagenia limbata)
Population – greater in forested streams as opposed to ag or residential http://www.insectidentification.org/imgs/
insects/giant-mayfly.jpg
The Mayfly Community
in nymph stage, shares stream bed with other benthic macroinvertebrate
As adults swarm with stonefly,caddisfly, for example
http://insects.tamu.edu/extension/youth/bug/bug003.html
Mayfly Niche
dwell in and around water sources laying their eggs in the water Eating habits
(larve/nymphs) are generally herbivores--eating plant materials like fine detritus and algae
Adults do not eat (only mate and die, live 90 min to 3 days)
Important important food for many species of fish
Mayfly - Habitat
Habitat – stream bed/above stream
http://images.google.com/imgres?imgurl=http://www.wiflyfisher.com/images/photos/sulphur-habitat.jpg&imgrefurl=http://www.wiflyfisher.com/sulphur-mayfly-
hatch.asp&usg=__rUH2BM4xyU_2R7PVIFzgVXLygyA=&h=384&w=512&sz=105&hl=en&start=3&um=1&itbs=1&tbnid=mxUc0Ps4wiK_3M:&tbnh=98&tbnw=131&prev=/images%3Fq%3Dmayfly%2Bhabitat%26gbv%3D2%26hl%3Den%26sa%3DN%26um
%3D1
Mayfly - Ecosystem
Freshwater Aquatic Ecosystem
http://www.nwfund.org/images/10sc060.jpg
Mayfly Biome
Freshwater Streams found in a Temperate Deciduous Forest
http://earthobservatory.nasa.gov/Experiments/Biome/Images/pictemperate.jpg
A community is composed of1. biotic and abiotic factors.2. several habitats.3. several abiotic factors.4. several populations.
Species X and Y are both at trophic level 2 and species Z is at trophic level 3. Which are the most likely relationships between the species? Relationship between:
Species X & Y Species Z & Xa. Mutualism Herbivoryb. Mutualism Competitionc. Competition Predationd. Parasitism Predation
Mutualism is an interaction between two species in which
1. one benefits and the other is harmed
2. both benefit3. one benefits and the other is
harmed.4. both are harmed
Which of the following is most likely to be a parasite?
1. A fungus in the living tissues of a tree2. A fungus cultivated as a source of food
by ants in their nest3. A fungus growing on the decaying
branch of a dead tree4. A caterpillar consuming the tissue of a
living fungus