Pyramids & Species

1. Pyramids & Species

2. 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) Structure & Pyramids in an Ecosystem 2.1.4 Pyramids in Ecosystems 2.1.5 How Pyramid Structure Affects Ecosystems

3. 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

4. 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

5. 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

6. 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

7. 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

8. 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).

9. 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

10. 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

11. 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

12. Ecosystem Function & Pyramids • "bottom-up" control - nutrient supply to the primary producers • "top-down" controls - predation and grazing by higher trophic levels

13. 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?

14. 2.1.6 Ecosystem Terms www.facstaff.bucknell.edu/ abrahmsn/bi356/

15. 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

16. 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

17. 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

18. 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.) www.archbold-station.org/.../ unit4/unit4intro.html

19. Habitat • The environment in which a species normally lives. • Example- woods, desert, swamp www.ebibleteacher.com/ images/swamp.jpg

20. Ecosystem • A community of interdependent organisms and the physical environment they inhabit http://blackhawkhomesteadnurscom.nxg.superpageshosting.com/ecosystem.jpg

21. Biome • A collection of ecosystems sharing similar climatic conditions, eg tundra, tropical rainforest, desert. http://www.donnalatham.com/images/Biomes_Cvr.jpg

22. 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

23. The May Fly • Species - Giant May Fly - (Hexagenialimbata) • Population – greater in forested streams as opposed to ag or residential http://www.insectidentification.org/imgs/insects/giant-mayfly.jpg

24. 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

25. 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

26. 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

27. Mayfly - Ecosystem • Freshwater Aquatic Ecosystem http://www.nwfund.org/images/10sc060.jpg

28. Mayfly Biome • Freshwater Streams found in a Temperate Deciduous Forest http://earthobservatory.nasa.gov/Experiments/Biome/Images/pictemperate.jpg

29. A community is composed of • biotic and abiotic factors. • several habitats. • several abiotic factors. • several populations.

30. 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 & X a. Mutualism Herbivory b. Mutualism Competition c. Competition Predation d. Parasitism Predation

31. Mutualism is an interaction between two species in which • one benefits and the other is harmed • both benefit • one benefits and the other is harmed. • both are harmed

32. Which of the following is most likely to be a parasite? • A fungus in the living tissues of a tree • A fungus cultivated as a source of food by ants in their nest • A fungus growing on the decaying branch of a dead tree • A caterpillar consuming the tissue of a living fungus