2 Biodiversity - Lecture notes 2 PDF

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Global Patterns of Biodiversity

Dr. Laci Gerhart-Barley BIS 2B, Fall 2018

Opening Question What time of year is shown in this diagram? A. June

B. September

C. December

Clouds

Equator

D. March

E. WTF?

Learning Objectives • Calculate diversity indices for different ecosystems/habitats • Understand how species richness and species evenness contribute to overall diversity indices • Describe global patterns of biodiversity and the physical and historical factors that contribute to these patterns • Interpret species-area and rarefaction curves

Levels of Biological Diversity Variation in characteristics

Groupings of species by physical environment

Habitat or Ecosystem (river, lake, ocean)

Groupings of species by evolutionary relatedness or ecological role

Higher taxa (genera, orders, phyla) Functional groups (e.g., predators)

Different species occupying the same habitat at the same time

Species

Differences in genotypes of individuals of the same species Different phenotypes among individuals with the same genotype

Genetic Plasticity

WE ARE HERE

How do we measure diversity? Kansas wheat field

Exuma Cay, Bahamas sea grass bed

Kansas tallgrass prairie

Hanauma Bay coral reef

Which environment is more diverse? Site A

Site B

Quantifying Diversity Diversity Index D Species Richness total number of species in the habitat

Species Evenness relative abundance of each species

D = (p1-p1)(p2-p2)( p3-p3)…(pn-pn) p is the proportion of individuals of that species

Which ecosystem is more diverse? Site A

Site B

How much do we sample? • Species-Area curve • How the number of species found changes with area sampled

• Rarefaction plots • How the number of species found changes with number of individuals sampled

Species Area Curves A

A

C B D

A F

B C B

C

A

B

C

F D

B

E A

B

B

B C

C

E A

C

D

B

E

Total number of species (cumulative)

C

A

DC D D F A

G

A B C F

E

G

C

8 6 4 2 0

1

2

4

8 16 Cumulative area sampled (m2)

32

Mauffrey et al 2007

Rarefaction Curves

Global Diversity Camilo Mora Univ Hawai’i

Prediction: 8.7 mill species

Mora et al 2011

Question You are an ecologist studying species diversity at the Jepson Prairie Reserve. You collect the data shown in the rarefaction plot below. What do these data indicate to you?

Question You are an ecologist studying species diversity at the Jepson Prairie Reserve. You collect the data shown in the rarefaction plot below. What do these data indicate to you?

Biodiversity • Climate • Temp/Precip • Seasonality

• Vicariance • Tectonic Plate Movement • Sea Level Change

• Regional Factors • Rainshadow Effect

What Controls Climate?

Hawai’i

Biomes outlined by dashed line heavily impacted by seasonality and disturbance (fire, grazing)

Kansas

California

Where in the Earth’s orbit does the month of June occur? A

B

D C

Equinoxes and Solstices

Tilt and Solar Energy What time of year is shown in this diagram? A. Winter

B. Spring

C. Summer

D. Fall

E. None of these

Hadley Cell

Hadley Cell and Biomes

Intertropical Convergence Zone

Intertropical Convergence Zone What time of year is shown in this diagram? A. June

B. September

C. December

ITCZ

Equator

D. March

E. WTF?

Vicariance • The geographic separation of a species into separate populations through some form of physical barrier Tectonic Plate Movement

Oxbow Lake Formation

Plate Tectonics

Plate Movement

Penguins of the World

Oldest fossil, ~62 mya

The Panamanian Land Bridge

Permian 225 MYA

Jurassic 135 MYA

Triassic 200 MYA

Cretaceous 65 MYA

Present Day

Islands and Sea Level 400,000 years ago, could an animal have walked from Mindanao to Samar? A. Yes B. No C. I have no idea what any of this means

Wallace’s Line

Alfred Russell Wallace

Regional Climate Factors How does the rain shadow effect impact patterns of diversity in montane ecosystems?

WEST

EAST

(Sacramento)

(Reno)

12000ft 10000ft

S Lo dg e

8000ft

i ne f u b a lp

pole

F ir F & Red

Y e llo w

6000ft 4000ft F

wood oothill

orest o r e st

p i ne

la n d s

er -J u n i p n o y n i P and Woodl

Sagebrush scrub

2000ft Valley grassland Rainfall

20

40

60

80

20

< 10

Regional Climate Factors Which region would you expect to be the DRIEST? A. The windward side of the Coast Ranges B. The leeward side of the Coast Ranges C. The windward side of the Sierra Nevadas D. The leeward side of the Sierra Nevadas

Understanding Rain Shadows In what direction are air masses moving? A. B. C. D. E.

From north to south From south to north From east to west From west to east What?...