Field Experience Course. October 30, 2014 BIO 182 Abe Borker

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1 Field Experience Course October 30, 2014 BIO 182 Abe Borker

2 Upper Campus Review field notes Favorite Plant, Pattern or Process? Have you been back? How many species of plants did you note? How many could you re-identify from your notes?

3 Ecology Basics

4 Scales in Ecology Biological or hierarchical scales Biosphere Biomes e.g. rainforest Biosphere landscapes Ecosystems & Landscapes Communities Communities Species Populations; breeding individuals Populations Individual organisms Individual

5 Global Scale (Lectures 6, 10) Biosphere Vegetation and animals Soil Rock Atmosphere Biosphere Crust Hydrosphere core (Lithosphere) Lithosphere Crust Mantle Crust (soil and rock) Biosphere (Living and dead organisms) Hydrosphere Lithosphere (water) (crust, top of upper mantle) Atmosphere (air)

6 Broad Spatial or Biome Scale (Lecture 6) World Vegetation Types or Biomes Coastal chaparral and scrub Coastal mountain ranges Sierra Nevada Mountain Coniferous forest Great American Desert Desert Coniferous forest Rocky Mountains Prairie grassland Great Plains Deciduous forest Mississippi River Valley Appalachian Mountains Role of climate 15,000 ft 10,000 ft 5,000 ft Average annual precipitation cm (40-50 in.) cm (30-40 in.) cm (20-30 in.) cm (10-20 in.) below 25 cm (0-10 in.)

7 Landscape Scale (Lecture 7) Coastmountain transition in western Norway

8 Geographical Scale (Lecture 7) Elevation gradient = gradual change Alpine tundra Montane coniferous forest Deciduous forest Temperate forest SEA

9 Community Scale (Lectures 1, 2) Populations of different species living and interacting within an ecosystem are referred to collectively as a community Often no real boundaries between communities

10 Community Boundaries: Often Gradual Land zone Transition zone Aquatic zone Number of species Species in land zone Species in aquatic zone Species in transition zone only

11 Deciduous forest and rocky shore = sharp change between communities

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13 How do we measure Organisms? Populations? Communities? Ecosystems?

14 Species Interactions There are different interspecific interactions, relationships between the species of a community. Predation/Exploitation (+/-) Competition (-/-) Mutualism (+/+) Commensalism (+/o) Amensalism (o/-) Neuteralism (o/o) Copyright 2002 Pearson Education, Inc., publishing as Benjamin Cummings

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16 Competition. Interspecific competition: can occur when resources are limited. Copyright 2002 Pearson Education, Inc., publishing as Benjamin Cummings

17 Ecological niche = the "role" a species "plays" in the ecosystem. An organisms use of biotic and abiotic resources in its environment

18 Contrast the ecological niche with the "habitat" which is the physical environment in which the organism lives.

19 The ecological niche of a species, therefore includes: species habitat abiotic & biotic interactions

20 No two similar species occupy the same niche at the same time.

21 Extinction of one species

22 extinction Constant food supply G. F. Gause (1934) tested competitive exclusion principle

23 Classic experiments confirm this. Fig Copyright 2002 Pearson Education, Inc., publishing as Benjamin Cummings

24 Resource partitioning: splitting the niche

25 Insect-eating warblers Sympatric species consume slightly different resources or use resources in slightly different ways

26 Character displacement: two similar species evolve in such a way as to become different from each other by accentuating their initial minor differences

27 Allopatric vs Sympatric populations

28 Allopatric populations: Similar beak morphologies and eat similar sized seeds

29 Avoids competition

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33 Predation. (Exploitation) A predator eats prey. Herbivory, in which animals eat plants. In parasitism, predators live on/in a host and depend on the host for nutrition. Predator adaptations: many important feeding adaptations of predators are both obvious and familiar. Claws, teeth, fangs, poison, heat-sensing organs, speed, and agility. Copyright 2002 Pearson Education, Inc., publishing as Benjamin Cummings

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36 Offset oscillations in the population sizes of the predator and prey Coevolution of predator and prey

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38 Plant defenses against herbivores include chemical compounds that are toxic. Animal defenses against predators. Behavioral defenses include fleeing, hiding, selfdefense, noises, and mobbing. Camouflage includes cryptic coloration, deceptive markings. Copyright 2002 Pearson Education, Inc., publishing as Benjamin Cummings Fig. 53.5

39 Mechanical defenses include spines. Chemical defenses include odors and toxins Aposematic coloration is indicated by warning colors, and is sometimes associated with other defenses (toxins). backside Devil scorpionfish

40 Mimicry is when organisms resemble other species. Batesian mimicry is where a harmless species mimics a harmful one. monarch viceroy

41 Müllerian mimicry is where two or more unpalatable species resemble each other. monarch queen Fig Cuckoo bee Yellow jacket Copyright 2002 Pearson Education, Inc., publishing as Benjamin Cummings

42 Mimicry blenny (Aspidontus taeniatus) mimics Hawaiian cleaner wrasse shortnose wrasse mimics Potter's angel which sports a defensive spine

43 Parasites and pathogens as predators. A parasite derives nourishment from a host, which is harmed in the process. Endoparasites live inside the host and ectoparasites live on the surface of the host. Parasitoidism is a special type of parasitism where the parasite eventually kills the host. Pathogens are disease-causing organisms that can be considered predators.

44 Coevolution and interspecific interactions. Coevolution refers to reciprocal evolutionary adaptations of two interacting species. When one species evolves, it exerts selective pressure on the other to evolve to continue the interaction. - flowers and pollinators - hermatypic coral and zooxanthellae - predator and prey - parasite and host

45 Mutualism Mutualistic symbiosis, or mutualism (+/+ interaction), is an interspecific interaction that benefits both species A mutualism can be Obligate, where one species cannot survive without the other Facultative, where both species can survive alone 2011 Pearson Education, Inc.

46 Figure 54.7 (a) Acacia tree and ants (genus Pseudomyrmex) (b) Area cleared by ants at the base of an acacia tree

47 Figure 54.7a (a) Acacia tree and ants (genus Pseudomyrmex)

48 Figure 54.7b (b) Area cleared by ants at the base of an acacia tree

49 Lobelia Hawaiian honeycreeper

50 Commensalism In commensalism (+/0 interaction), one species benefits and the other is neither harmed nor helped Commensal interactions are hard to document in nature because any close association likely affects both species 2011 Pearson Education, Inc.

51 Figure 54.8

52 Facilitation Facilitation ( / or 0/ ) is an interaction in which one species has positive effects on another species without direct and intimate contact For example, the black rush makes the soil more hospitable for other plant species 2011 Pearson Education, Inc.

53 Number of plant species Figure (a) Salt marsh with Juncus (foreground) (b) 0 With Juncus Without Juncus

54 Figure 54.9a (a) Salt marsh with Juncus (foreground)

55 But how do entire communities structure?

56 Food Chains Artificial devices to illustrate energy flow from one trophic level to another Trophic Levels: groups of organisms that obtain their energy in a similar manner This is a simplification of relationships

57 Antarctic Food Web

58 Draw a Fort Ord Foodweb

59 Keystone Species A species whose presence in the community exerts a significant influence on the structure of that community.

60 Paine s study on Pisaster and blue mussels

61 An Ecological Mystery

62 Keystone Species Kelp Forests

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64 An Ecological Mystery Long-term study of sea otter populations along the Aleutians and Western Alaska 1970s: sea otter populations healthy and expanding 1990s: some populations of sea otters were declining Possibly due to migration rather than mortality 1993: 800km area in Aleutians surveyed - Sea otter population reduced by 50%

65 Vanishing Sea Otters 1997: surveys repeated Sea otter populations had declines by 90% : ~53,000 sea otters in survey area : ~6,000 sea otters Why? - Reproductive failure? - Starvation, pollution disease?

66 Cause of the Decline 1991: one researcher observed an orca eating a sea otter Sea lions and seals are normal prey for orcas Clam Lagoon inaccessible to orcas- no decline Decline in usual prey led to a switch to sea otters As few as 4 orcas feeding on otters could account on the impact - Single orca could consume 1,825 otters/year

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69 BIG CREEK!

70 Weather Expect rain on Saturday! Waterproof shoes! Rain jacket / hat / hood Rain pants if you have tem Change of dry clothes! Cold front comes in Friday FORTY SIX DEGREES AT NIGHT, BRRRRRR!

71 Weather Expect rain on Saturday! Waterproof shoes! Rain jacket / hat / hood Rain pants if you have tem Change of dry clothes! Cold front comes in Friday FORTY SIX DEGREES AT NIGHT, BRRRRRR!

72 Fun stuff!

73 Other Fun stuff! Bathing suit (there s a very COLD creek) Snorkel mask and wetsuit if interested. Towel! Musical Instruments JAFFLE ingredients!

74 More Fun stuff! Big Creek has a huge diversity of habitats Cobble Beach Riparian Oak Woodland Redwood Forests Steep Canyon walls, and big elevation gradients

75 Rough Plan Saturday LEAVE 7am SHARP!!!!! Arrive ~10am Explore Big Creek Habitats Sunday Natural History / Rapid Research 3pm

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