1.25.13• Test on Tuesday• Quizlet due Tuesday• Homework: Read 5.2, 5.3, 5.4
Review• Describe the processes that create a rain shadow• On a map identify regions of the globe that are affected by rain shadows• Explain how abiotic conditions determine the characteristics of a biome
Objectives• Describe the importance of biodiversity.• Differentiate between species richness and species evenness.• Utilize Shannon’s index to calculate species diversity.
Question• Why does a healthy lawn need 4 types of grass?
Levels of Biodiversity• Does anyone recall the 3 levels of biodiversity? • Ecosystem • Species • Genetic
Levels of Biodiversity• In general, will greater biodiversity be found on tended land or untended land?• Why?
Levels of Biodiversity• Of the three levels of biodiversity, which one ultimately determines the other two?
Richness vs. Evenness• Why is the number of species on earth not a useful indicator of local or regional diversity?• Species aren’t distributed evenly over the face of the earth.
Richness vs. Evenness• If you had to define SPECIES RICHNESS vs. SPECIES EVENNESS, how would you do it?
Richness vs. Evenness• Richness: The number of species in a given area• Gives a sense of the biodiversity in an area
Richness vs. Evenness• Evenness: Relative proportions of individuals within the different species• Are there equal numbers of many species?• Is the area dominated by one species?
Richness vs. Evenness• High Evenness • All species have a relatively equal number of individuals
Richness vs. Evenness• Low evenness • One species has many individuals • Other species have only a few
Richness vs. Evenness• Could an ecosystem have low evenness and still be rich?• If two areas have the same richness ...• The more even ecosystem is considered more diverse
Shannon’s Index• Used to calculate the biodiversity present in an area• H = -∑ pi ln (pi)• Shannon’s Index = [(% A X (ln % A)) + (% B X (ln % B))]• Example: 3 Species: Species A 75%, Species B 15%, Species C 10%• Calculate the Shannon’s Index for each sample on the next slide
Sample 1 Sample II Sample IIISpecies A 24 48 24Species B 20 40 20Species C 7 14 7Species D 3 6 3Species E 3Species F 1 Index
Sample 1 Sample II Sample IIISpecies A 24 48 24Species B 20 40 20Species C 7 14 7Species D 3 6 3Species E 3Species F 1 Index 1.15 1.15 1.36
Why is BD Important• Get out a sheet of paper• Write a D on the top of your paper• Walk around and write down the names of 3 people
Why is BD Important• Everyone remain standing• I am the disease• When your name is called sit down• How many are left standing?
Why is BD Important• 2D• N - Noble Fir• C - Western Cedar• M - Vine maple• H- Hemlock• W - Fir• L - Pine
Agenda• Garbage Patch projects due Tuesday• Should have completed packet reading• Completed lab will be due next Friday
Reading Quiz• Name 1 way in which evolution occurs• How are artificial and natural selection alike, how are they different?• How does evolution lead to biodiversity?• How does geographic isolation lead to reproductive isolation?
Objectives• calculate diversity values for sampled habitats, using three indices: species richness, Shannon-Wiener, and Simpson’s• Explain trade-offs involved in establishing biodiversity reserves.• Understand rationales for maintaining biodiversity when possible.• Understand subtle differences between the different ways of measuring and defining biodiversity
Berlese Funnels• What are some possible reasons for low microarthropod captures?• How could the experiment be altered to obtain better data?• Use hand lenses and dissecting scopes to determine if you have anything in your alcohol
Schedule• Go outside and collect sticky traps• Come inside and begin to crunch data• Look at photos from yesterday• Analyze trap catches and gather data• Work through Berlese Funnel catches• Start questions
Agenda• Hope you turned in your garbage patch work• Chapter 4 and 5 test tomorrow• Lab due Friday
Objectives• Explain the terms fundamental niche, realized niche, niche generalist, and niche specialist.• Relate environmental change to species distribution.• Compare and contrast major mass extinctions
Question• Is it better to be mediocre at many things or excellent at one thing?
Niches• How would you define Range of Tolerance? • The minimum and maximum amount of any factor that an organism can handle
Niches• Range of Tolerance • At either end of the spectrum an organism may survive but not thrive.
Niches• Fundamental Niche • The combination of all ideal conditions for an organism • Determined by abiotic factors
Niches• How could biotic conditions limit a species range or survival?
Niches• Realized Niche • The combination of biotic and abiotic conditions under which an organism survives • Once realized niche is determined distribution can be understood.
Niches• Some species can thrive under a wide variety of environmental conditions.• Large Realized Niche• Known as NICHE GENERALISTS
Niches• Some species can only thrive only under a very small set of conditions.• Small realized niche• Known as a NICHE SPECIALIST
Niches• Where do you think generalists are likely to be found?• Specialists?
Niches• We’ve seen that environmental conditions determine what lives where.• What do you think will happen if the environment changes?
Climate Change• Organisms follow the conditions.• New areas are colonized by new species.• How do you think this relates to disease transmission?