I. BIODIVERSITY (CH2, CH10, CH3 plus 3 “big articles”)

Intro to terms -Levels of biodiversity

A. History of biodiversity (and extinction) on earth

B. Where is biodiversity on earth and why?

C. How many species do we have? (Fri)

D. Extinction today

E. Relationships between ecosystem functioning, ecosystem services and biodiversity.

I. BIODIVERSITY

Intro to terms -Levels of biodiversity

Species diversity

II. Biodiversity

A. Species diversity

Genetic diversity

biomes, landscapes, ecosystems, habitats, niches, population

Community diversity

Your text…has table below

Despite all this we really focus on organism level.

Some more details…

In ecology… diversity is also more technically referred to as richness

What is the richness of each of these communities?

Is richness a great way of describing these two communities?

Species richness vs evenness

evenness=relative abundance of each species

A little more terminology…

Other ways of thinking about measuring diversity…

Alpha diversity is the within-habitat diversity

number of species per habitat

Beta diversity is the between-habitat diversity

number of different habitats

Gamma diversity= # species in a given large area like continent

A. History of biodiversity (and extinction) on earth

1. Precambrian before about 500mya

Ends with Cambrian explosion2. Paleozoic

Ends with the “End Permian” Extinction3. Mesozoic

Ends with the Cretaceous Extinction (K/T) 4. Cenozoic

5. Anthropocene

PRECAMBRIAN

PRECAMBRIAN

Oldest fossils are Prokaryotes-

What are Prokaryotes?Stromatolites (3.5bya)

Precambrian Ends with..Cambrian explosion about 500mya

Paleozoic Period about 500-250myaClimate-Moist SwampyPlants-ferns, mosses, horsetailGiant insects

Many diverse amphibians were large! 9ft

Science DailyTiktaalik roseae, an early tetrapodomorph (late Devonian period, ~380 M. y. ago) (Credit: Arthur Weasley, GNU Free Documentation licence)

And scary fish

nationalgeographic.com

Many Diverse Synapsids

A dicynodont

Thrinaxodon-cynodont

More Synapsids

Figure 23.4a

OTHERTETRAPODS

Reptiles(includingdinosaurs and birds)

Mammals

†Very late (non-mammalian)cynodonts

†Dimetrodon

Cyn

od

on

ts

Th

erapsid

s

Syn

apsid

s

Paleozoic Ends with the “End Permian Extinction” 250mya

Effect 90-96% of all species

Why?Huge amounts of lava oozing out of the earth Siberia- lasting millions of years…heat CO2 and sulfur dioxide

http://www.nationalgeographic.com/ngm/0009/feature4/

Mesozoic about 250-65mya•Dinos super diverse! •Mammals around..•Flying and pollinating insects begin to diversify with flowering plants

Mesozoic about 250-65mya•Dinos and diverse other reptiles! Mammals around..•Flying and pollinating insects begin to diversify with flowering plants

Mesozoic Ends with…Cretaceous Extinction event (K/T)! 65mya

Figure 23.10

Time (mya)

Paleozoic Mesozoic Cenozoic

542 488 444 416 359 299 251 200 145 65.5 0

E O S D C P Tr J PC N Q

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EraPeriod

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Average species lives 1-10my

One Bryzoan has been on the planet for 85 my! (p34)

All Invertebrates Raup (1978) 11Marine Invertebrates Valentine (1970) 5–10Marine Animals Raup (1991) 4Marine Animals Sepkoski (1992) 5All Fossil Groups Simpson (1952) .5–5Mammals Martin (1993) 1Cenozoic Mammals Raup and Stanley (1978) 1–2Diatoms Van Valen 8Dinoflagellates Van Valen (1973) 13Planktonic Foraminifera Van Valen (1973) 7Cenozoic Bivalves Raup and Stanley (1978) 10Echinoderms Durham (1970) 6Silurian Graptolites Rickards (1977) 2Adapted from the book “extinction rates”, edited by Lawton, J, and May, R.[8] Wikipedia!!

http://www.planetunderpressure2012.net/images/anthropocene_cartoon.jpg

http://www.igbp.net/news/opinion/opinion/haveweenteredtheanthropocene.5.d8b4c3c12bf3be638a800

https://www.youtube.com/watch?v=fvgG-pxlobk

I. BIODIVERSITY

A. History of biodiversity (and extinction) on earth

B. Where is biodiversity on earth and why?

C. How many species do we have? (last Fri)

D. Extinction today (Today and Wed)

E. Relationships between ecosystem functioning, ecosystem services and biodiversity.

Biodiversity and where it is found..(Text 2.3)

•Land and water-do look at!

•Major biogeographic realms and ecoregions (Neotropics, Afrotropics, Nearctic..Western Indo Pacific etc…)

•Altitude and depth…

We will mostly focus on latitude

10 ha of forest in Brazil might have 300 species

10 ha of forest in US might have 30 species

Ants (Fischer 1960)

Brazil 222

Trinidad 134

Cuba 101

Utah 63

Iowa 73

Alaska 7

Arctic Alaska 3

Snakes

Mexico 293

U.S. 126

Canada 22

Freshwater fish

Lakes Victoria/Tanganyika/ Malawi each have about 1450 species

Amazon more than 1000

Central America has 456

North America 173

Marine inverts-planktonic crustaceans

Great Barrier Reef

50 genera of coral vs. 10 genera

Is the north or south end more diverse?

Marine bivalves

Butterflies

Lizards

Why do we see this pattern? (not so clearly ordered in your text-p38)

Hypotheses……

1.Energy

What does this mean? How might amount of energy reaching the earth affect the number of species?

More solar radiation->>more photosynthetic activity->>more resources->>more species

2. Evolutionary Time

What does this mean? Why might tropical areas be “older”?

All communities diversify over time because they accumulate species

Older communities will have more species than younger communities

tropical biotas ---”mature”

temperate and polar biotas ---”immature communities”

EX. Lake Baikal is one of the oldest lakes in the world

580 species of benthic invertebrates

Great Slave Lake Canada

4 species in (comparable area, latitude)

3. Spatial heterogeneity (i.e., topography)

Why might areas that vary lots in topography have more species?

The more complex the physical structure of the environment

1. Many different kinds of habitats.

But also..

2. Speciation is encouraged-populations are easily isolated from one another….

4. Climatic stability Why might a more stabile climate increase diversity?

means lower levels of extinction (museum of diversity)

Another factor that directly affects number of species is…

5. Size of area (Island Biogeography)

Note: may or may not relate to why tropics is hi in diversity…

Plants on small islands in Bahamas

Birds on lakes

Bats and caves Springs in Australia

Fig 10.3

I. BIODIVERSITY

A. History of biodiversity (and extinction) on earth

B. Where is biodiversity on earth and why?

C. How many species do we have?

E. O. Wilson-Mr. Biodiversity

The Ants

The Diversity of Life

http://www.youtube.com/watch?v=knLdKcx6VXk

History of our attempts to count species

• Linnaeus-1758-described about 12,000 species

• Number of described species today 2 million extant (your text p30)

• In Mora paper…Used database of 1.2 million• “catalogued 1.5 million”

• Much of the uncertainty revolves around number of insects… (and what other major group/s?)

Extrapolating actual number#1 (May)

•Assume all mammals have been identified.

•Found ratio of 1/3 Temperate to 2/3 Tropical mammals

•Assume all the Temperate insects have been identified (1 million)

•Then if this ratio is maintained we can extrapolate -----numbers of tropical insects should be .. ? 2 million (total insects should be?)

Extrapolating actual number#2 (May)https://canvas.sfu.ca/courses/.

10 8=100 million total

67/22,000

The guy that wrote your chapter!

Extrapolating actual number#3 (Gaston)

67/22,000 = 15,000/N

The guy that wrote your chapter!

Extrapolating actual number#4 (Erwin)

•Insecticidal fog

•Estimated number of species in a specific tree

•Then extrapolated given the number of tree species (a better known taxon)

•Argues for 30 million insects alone

2 million described +

May said add 2 million more for insectsMay said add 100 million based on sizeGaston said add 5-6 million more for insectsErwin said add 30 million more for insectsPimm a well respected ecologist said 100 million

(Some of these estimates are referred to in Table 1 of article for Friday…)

What organisms are NOT included in these estimates???

1. Why bother with the hopeless task of counting species?  2. Review the nested nature of taxonomy!

3. What did they do with the “1.2 million currently valid from several publicly accessible sources”? What do they mean temporal accumulation curves of different taxa?  Why would they be interested in when we discover species over time?

4. What do the graphs in Figure 1A-F show?

What about graph 1G, what does it show?

5. What does Figure 2 show? What do they mean they are validating their approach?

6. What are at least two of the limitations of this approach that they describe?

7. What do you notice about Table 2? (FYI the Chromista are the non Protozoan Protists)

How do these numbers compare with the estimates we went over?  From the table, what groups have we done a good job with in terms of finding/identifying species and which have we done a poor job?

7. What were the main points of the critics of the paper? (Zimmer article and Eisen’s blog)

There is a good analogy concerning a pyramid-did you notice?

http://www.dnr.state.mn.us/ecs/index.html