Slide 1 CHAPTER 7: COMMUNITY ECOLOGY STRUCTURE SPECIES INTERACTION SUCCESSION SUSTAINABILITY

Slide 2 COMMUNITIES AND STRUCTURE ISLAND BIOGEOGRAPHY SPECIES TYPES IN COMMUNITIES SPECIES INTERACTIONS PLANT SUCCESSION STABILITY AND DISTURBANCE TOPICS AND CONCEPTS CHAPTER 7

Slide 3 COMMUNITY STRUCTURE Structure can be thought of as: Physical – for example the diameter of trees, canopy cover and layers of vegetation or tree partitioning by various animal species such as finches. Spatial patterns – populations dispersed randomly, clumped or uniformly. Biodiversity Abundance - the number of individuals of a species in an area Richness - the number of different species in an area which is a useful measure of the variety of ecological niches or genetic variation in a community. It decreases as we go from the equator towards the poles Genetic – gene frequency; number of alleles, etc. Habitat changes – frequency of habitat changes through a fixed distance Trophic level complexity – number of food chains (webs) in a system Number and types of services provided by natural capital – for example water purification Productivity (discussed in chapter 4, pp )

Slide 4 mft Tropical rain forest Coniferous forest Deciduous forest Thorn forest Tall-grass prairie Short-grass prairie Desert scrub Thorn scrub Figure 7-2 Page 141 COMPARISON OF PHYSICAL STRUCTURE OF THE WORLD'S TERRESTRIAL BIOMES

Slide 5 Click to view animation. Species by latitude animation. Animation

Slide 6 Figure 7-3 Page 142 Species Diversity 1, Latitude 80ºN ºN ºS60 Latitude WHAT AFFECTS BIODIVERSITY? LATITUDE?

Slide 7 Number of individuals per diatom species Number of diatom species Unpolluted stream Polluted stream Figure 7-4 Page 142 HOW DOES POLLUTION AFFECT DIVERSITY?

Slide Percentage disturbance Species diversity Figure 7-13 Page 154

Slide 9 THEORY OF ISLAND BIOGEOGRAPHY – diversity of isolated area is a function of: –Factors that influence diversity on islands are: Size Degree of isolation (distance from mainland) Age of island –Species reach equilibrium where immigration rate equals extirpation rate (not extinction!!!) –Galapagos are a classic example of this. San Juans follow this model. What about the Hawaiian Island chain?

Slide 10 High Low Rate of immigration or extinction Equilibrium number Immigration and extinction rates Number of species on island (a) Figure 7-5 (1) Page 143 © 2004 Brooks/Cole – Thomson Learning

Slide 11 High Low Rate of immigration or extinction Small island Effect of island size Number of species on island (b) Large island Figure 7-5 (2) Page 143 © 2004 Brooks/Cole – Thomson Learning

Slide 12 High Low Rate of immigration or extinction Far island Effect of distance from mainland Number of species on island (c) Near island Figure 7-5 (3) Page 143 © 2004 Brooks/Cole – Thomson Learning

Slide 13 Click to view animation. Animation Area and distance effects interaction.

Slide 14 SPECIES TYPES IN COMMUNITIES –Keystone (flying fox) –Indicator (amphibians) –Exotic or invasive (Himalayan blackberry) –Top predator (killer whales, lions, wolves)

Slide 15 Figure 7-6 Page 145 sperm Eggs Sexual reproduction Fertilized egg development Organ formation Egg hatches Tadpole develops Into frog Young frog Adult frog (3 years) AMPHIBIANS ARE GOOD INDICATOR SPECIES

Slide 16 SPECIES INTERACTIONS –Commensalism –Mutualism –Competition –Predation –Parasitism – role in macroevolution with the development of eukaryotic cell (predate, exploit to coexistence)

Slide 17

Slide 18 Number of individuals Resource use Species 1Species 2 Region of niche overlap Species 1Species 2 Figure 7-7 Page 147 © 2004 Brooks/Cole – Thomson Learning COMPETITION LEADS TO RESOURCE PARTITIONING

Slide 19 Figure 7-8 Page 148 HERE THE RESOURCE PARTITIONED IS LOCATIONS ON THE TREE

Slide 20 Span worm Bombardier beetle Viceroy butterfly mimics monarch butterfly Foul-tasting monarch butterfly Poison dart frog When touched, the snake caterpillar changes shape to look like the head of a snake Figure 7-9 Page 150 Wandering leaf insect Hind wings of io moth resemble eyes of a much larger animal DIFFERENT TYPES OF MIMICRY TO AVOID PREDATORS MIMICRY IS LOOKING OR ACTING LIKE OTHER SPECIES TO AVOID BEING EATEN. 2 TYPES ARE MULLERIAN AND BATESIAN

Slide 21 Figure 7-10 Page 151 Oxpeckers and black rhinocerosClown fish and sea anemone Mycorrhizae fungi on juniper seedlings in normal soil Lack of mycorrhizae fungi on juniper seedlings in sterilized soil EXAMPLES OF MUTUALISM

Slide 22 COMMUNITY DYNAMICS PLANT SUCCESSION MODELS –The book gives primary and secondary models (a spectrum in reality). Primary succession is like cooking from scratch, secondary is when the structure is changed, but the ecosystem is able to rebuild from what is left. Plant invasion of cooling lava is a good example of primary; regeneration after fires is a good example of secondary. Three basic models more realistic (especially when stochastics are considered) are –Facilitation or relay floristics (Clemens vs. Gleason) –Inhibition –Competition STABILITY –Persistence – resistance to being disturbed or altered –Constancy – ability to keep population numbers within limits imposed by available resources –Resilence – ability of community to recover after disturbance –Restoration (back to original form and function) vs. rehabilitation (fix it up and restore partial function.

Slide 23 Time Small herbs and shrubs Heath mat Jack pine, black spruce, and aspen Balsam fir, paper birch, and white spruce climax community Exposed rocks Lichens and mosses Figure 7-11 Page 152 PRIMARY ECOLOGICAL SUCCESSION FACILITATION (RELAY FLORISTICS) MODEL DEVELOPED BY CLEMENS

Slide 24 Time Annual weeds Perennial weeds and grasses Shrubs Young pine forest Mature oak-hickory forest Figure 7-12 Page 153 SECONDARY ECOLOGICAL SUCCESSION

Slide 25 THIS IS THE END OF CHAPTER 7 THE TEST WILL COME FROM THESE LECTURE SLIDES!!!!!! USE THE TEXT TO CLEAR UP POINTS OR TOPICS THAT ARE NOT CLEAR TO YOU. THANKS FOR STUDYING ENVIRNOMENTAL SCIENCE