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Adaptations & the Physical Environment

FIELD BIOLOGY & METHODOLOGY Fall 2013 Althoff. Lecture 03. Adaptations & the Physical Environment. Kangaroo rat. Tolerance Limits. Limiting factors vs. zone of tolerance (~ concentration gradient???)

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Adaptations & the Physical Environment

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  1. FIELD BIOLOGY & METHODOLOGYFall 2013 Althoff Lecture 03 Adaptations & the Physical Environment Kangaroo rat

  2. Tolerance Limits • Limiting factors vs. zone of tolerance (~ concentration gradient???) • Zones (handout): a) optimum range b) zone of physiological stress c) zone of intolerance

  3. Popn abundance Gradient HIGH LOW

  4. Tortugas individuals Halifax individuals Pulsations/minute Temperature 0C _____ species of Jellyfish (Aurelia aurita) but from different populations (genetic variation increasing adaptability to local environment!!!).

  5. Tolerance Limits…con’t • Simplistic view: one factor “acting” at-a-time • Reality: _________________ of factors • ________ factor: “one factor…more than any other…determines distribution & abundance”

  6. Adaptations Modifications which better suit the organism to its particular environment vs. Gray wolf: colder climate African hunting dog: warmer climate Notice: _______________________

  7. Adaptations…con’t • May allow control “flux” of heat or various substances across their surfaces • By regulating __________ with physical environment, internal environment can be controlled better. “Can move or adjust”

  8. Specific examples • Salt and water balance • Nitrogen excretion • Temperature & water conservation • Plant-water relationships • C3, C4, & CAM Photosynthesis

  9. Fish: ______________________ actively exclude or retain solutes to maintain salt balance

  10. Highly developed __________ in kidneys…. allows for maximum retention of H20 during urine formation Urine almost comes out paste-like. Animal almost exclusively gets all of its water from seeds (i.e., metabolizes H20) Kangaroo rat: found in dry, arid or semi-arid environments

  11. C3 (cool season plants) • Plants well-adapted to “average” temperature and “average” moisture conditions … think ________________ • Relates to C-assimiliation • Examples: Kentucky bluegrass, maples, dandelion

  12. C4 (warm season plants) • Plants well-adapted to hot temperature and “average” moisture conditions …. think _______________ • Relates to C-assimilation • Examples: big bluestem, switchgrass, tomatoes, corn, sunflower

  13. CAM • Plants well-adapted to hot temperature and “dry” moisture conditions (i.e., arid conditions) • Carbon assimiliation daytime, Calvin cycle nighttime • Examples: cacti & prickly pear

  14. Back to “environmental conditions” Most organisms have “optimum range.” Within that concept, there are eurytypic and stenotypic organisms

  15. Range of Tolerances • _________________ -- species with wide tolerance ranges ex:white-tailed deer & “any” habitat combination • _________________ -- species with narrow tolerance ranges ex: Kirtland’s warbler & jack pine

  16. Seasonal Cycles – Temperate Lakes • Understand the temperature profile of a typical lake related to seasonal changes (Fig. 4.13, p82) • ____________—zone of rapid change. Marks boundary between epilimnion (warm) and hypolimnion (cold) waters

  17. Topographic and Geologic Influences The “lay” of the land influences the local environment. Soil and exposure have profound influences on ___________ and therefore __________ distribution

  18. Lay of the land….

  19. Tbasic soil types Ricklefs Table 4.2, p90

  20. Local Variations • RIPARIAN—forested zones along rivers, creeks, and streams • XERIC—dry sites • MESIC—”in between” sites • HYDRIC—wet sites

  21. Life Zones • Distinct “_______” of vegetation. Belts are a result of local climate which influences vegetation… …which influences animal diversity and distribution

  22. Life Zones Fig 4.20 p89

  23. Lower Sonoran zone: saguaro cactus, mesquite, herbs

  24. Upper Sonoran zone: agave and grasses

  25. Transition zone: ponderosa pine

  26. Alpine zone: higher up, bushes, herbs, lichens

  27. Landscape Ecology • Study of the __________ nature of the environment influences the functioning of the ecosystem • Emphasis on movement between habitats by organisms • Human influence on landscape is tremendous

  28. In summary… • Mechanisms by which organisms interact with their physical environment help us understand why organisms are specialized to ______________ _________________ • Plant species ___________(C) in one of three ways: C…C3 pathway, C4 pathway, or CAM pathway. Each way is specialized to provide a competitive advantage under certain sets of climatic conditions • ____________ represent result from climatic influences on plants, which in turn have influences on the distribution of animals

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