1. Biodiversity
Chapter 12

2. Biodiversity
Biodiversity - the variety of living things - three types essential:
Genetic diversity - variety of different versions of the same genes within a species
Species diversity - number of different kinds of organisms within an ecosystem
Ecological diversity - complexity of a biological community (number of niches, trophic levels, etc.)
Adding to the concept of biomes, we now want to consider the concept of biodiversity (how varied living material is in a system). There are three basic kinds of biodiversity. The most commonly used is species biodiversity. However, within any species there can be a large or a relatively small amount of genetic diversity. For instance, let's consider two different species. First, let's take a species of wasp that feeds only on the pollen of one particular flower located in a very small part of a tropical rain forest. The wasp would die out if the flower were not present. The wasp is probably a species that exhibits a small amount of genetic diversity. We could also consider a species like Douglas-fir that is found all the way from British Columbia down to southern California. and also lives in two very different types of temperature and moisture regimes. For instance, it lives in both western and eastern Washington. Western Washington is cooler and wetter in the summer than eastern Washington, where it gets very hot and dry. We can conclude from its wide and varied distribution that Douglas-fir is a species with a lot of genetic diversity.
We can also have ecological diversity, which consists of the niches or functions that species display within an ecosystem. If those are diverse, the system could be considered diverse as well. If we have a number of species that effectively do the same thing within an ecosystem, the ecosystem would not be as ecologically diverse as one in which organisms had a variety of ecological roles.
It is easier to just count species as a measure of biodiversity, and this is probably why the common use of the term biodiversity refers to this measure.

3. Is there an equal distribution among groups of organisms?
Current Estimates of Known Living Species by Taxonomic Group (IUCN, 2005)
Mammals 5,416
Birds 9,917
Reptiles 8,163
Amphibians 5,743
Fishes 28,500
Insects 950,000
Mollusks 70,000
Crustaceans 40,000
Other invertebrates 130,200
Ferns, mosses, and lichens 38,025
Gymnosperms 980
Grasses 59,300
Flowering plants 199,350
TOTAL 1,545,594
How many species exist?
Is there an equal distribution among groups of organisms?
There are big questions in the study of biodiversity. Perhaps the biggest is just how many species there are. Some species are easily identified (flying birds, and plants such as Douglas-fir). Others, particularly small organisms that aren't easy to see, and organisms that live in environments that humans don't often visit, are much more difficult to count. In particular, if we take the insects, we find that they are incredibly diverse; and so it is very difficult to catalogue all of them.
We have only scratched the surface of the number of species that exist, but we recognize that over a million species have been identified so far. This is probably only a fraction of the species that exist, particularly for poorly characterized organisms like insects and mites. The estimates for mammals and birds are stable (it is rare to discover a new species in these groups today), so there are probably fairly good estimates of the number of species that exist today. Another question that needs to be asked in making tallies of species is, "What exactly constitutes a species"?
IUCN - International Union for Conservation of Nature

5. Biodiversity Hotspots
Most of the world's biodiversity concentrations are near
the equator (tropical rainforests, coral reefs).

6. Biodiversity through time
Biodiversity is not stable through time
Extinction
common phenomenon
natural process - one species lost every 10 years
accelerated by human impacts on populations and ecosystems
E.O. Wilson - we are currently losing thousands of species a year
Dynamic earth/solar system process
results in changes of climate & land masses

7. Changes Through Time

8. The Dynamic Earth The earth’s continents are on plates
These continental plates rest on liquid (mantle) and continue to shift
The present-day arrangement of the plates (continents) has not always been so…….

9. Continential Drift 225 million years ago 135 million years ago
present

10. Geologic Time is measured with Extinction Events: six major extinction episodes - we are living the 6th
What role does extinction have on biodiversity?
6. Current Extinction Crisis: caused by human activity
5. Cretaceous: ruling reptiles (dinosaurs); many marine species
4. Triassic: 35% of animal families, including many reptiles and marine mollusks
3. Permian: 50% of animal families, including 95% of marine species; many trees, amphibians, etc.
2. Devonian: 30% of animal families
1. Ordovician: 50% of animal families

11. Adaptive Radiation of organisms
if habitat remains, mass extinction can lead to rapid evolution
due to vacated ecological roles left by extinct species
one example is the mammal “explosion” in the Cenozoic

12. Species Decline after human contact
hoofed
animals
flightless birds

13. Causes of Extinction - HIPPO
1. Habitat loss
2. introduction of Invasive (non-native) species
problems arise from competition (exotic out-competing natives)
3. Pollution
4. Population (human)
5. Overharvesting

14. What value is Biodiversity?
Research and education value
Recreational Value
Intrinsic Value
Aesthetic Value
Life support Value
Economic Value

15. What habitats are in peril?
Endangered and Threatened Species Worldwide from IUCN Red List, 2014 (with % of total)
Mammals 1,199 (26%)
Birds 1,373 (13%)
Reptiles 397
Amphibians 1,957 (40%)
Fish 2,222
Insects &other invertebrates 4,140
Total Fauna 11,288
Plants (Flora) 10,595 (40%)
four habitats in particular
tropical rain forest
estuaries
wetlands
coral reefs
This slide shows the number of endangered and threatened species worldwide that are listed by the US Fish and Wildlife Service. You'll notice that hundreds of species of animals and plants are presently listed as endangered or threatened. This shows that the potential for extinction of many of these species is there. Many of their problems are being addressed, but many are not.
International Union for Conservation of Nature

16. Habitat Loss: tropical rain forest
less than 1/2 exists today
perhaps all gone by 2030
7% of land mass
50% of species
complex and biodiverse
poor soil, since 90% of nutrients are contained as biomass

17. Habitat Loss: estuaries
Pacific Northwest
bays where rivers empty into the sea
mix fresh and salt water
calm, warm, nutrient-rich
65% of marine fish and shellfish use estuaries and saline wetlands for spawning and juvenile development
help stabilize shoreline and reduce storm damage inland
Chesapeake Bay

18. Habitat Loss: wetlands
shallow ecosystems
saturated or submerged land surface
support rich biodiversity
migrating waterfowl
1/3 of all endangered species spend part of their lives in wetlands
retain storm water and reduce flooding
filter/purify urban and farm runoff
swamps
wetlands with trees
marshes
wetlands without trees
bogs
water-saturated ground
ground composed of deep layers of accumulated, undecayed vegetations known as peat
less biologically diverse, yet unique species reside
fens
bogs fed by groundwater

19. Habitat Loss: coral reefs
among the most species-rich and productive ecosystems in the world
reefs are colonies of small colonial animals (polyps) that live symbiotically with photosynthetic algae
60% of world reefs are at risk from human activities

20. Strategies for Conserving Biodiversity
Read carefully pages
develop an answer to the question:
Describe different strategies for conserving biodiversity from global to local levels.

21. Island Biogeography
What happens to species number as the island gets further away from source pool?
species # as distance of source pool 
What happens to species number as the island gets smaller?
species #  as surface area 
study of facts and patterns of species distribution in/on islands
two important variables to consider
island’s distance from a source pool of species
surface area of an island

22. Island Biogeography
So, what would you predict in the Wisconsin forest example?

23. National Parks as Isands

24. Conserving Biodiversity
Population biology principles (p. 465)
small populations of a species are more likely to become extinct than large populations
easier to prevent “endangered status” than “endangered” to extinct
to understand a population, important to consider age structure and sex ratio
populations must be monitored to determine the effects of a conservation plan on the status of a species

25. Conserving Biodiversity
Conservation biology principles (p. 466)
species less likely to become extinct if broadly distributed across its range
habitat characteristics favoring species preservation:
large rather than small in size
close together rather than widely separated
whole rather than internally fragmented
linked by “corridors” rather than isolated
broad rather than long and narrow
inaccessible rather than easily accessible to people

26. Applying Island Biogeography
read pages
Answer question #1, p. 469
Answer question #2, p. 469
Answer question #3, p. 469