1. CHAPTER 4 Biodiversity and Evolution

2. Core Case Study: Why Should We Protect Sharks?
400 known species
Only _____ deaths per year from shark attacks but _________________ sharks killed every year
Caught for their _____________ (finning)
Organs, meat, hides
Fear
32% of shark species threatened with extinction
Act as _______________ species that keep their ecosystem functioning
Cancer resistant…we could use this information to fight cancer in own species 6
million
fins
keystone

3. Threatened Sharks Hammerhead Shark Eats stingrays Whale Shark
Figure 4.1: The threatened whale shark (left), which feeds on plankton, is the largest fish in the ocean. The endangered scalloped hammerhead shark (right) is swimming in waters near the Galapagos Islands, Ecuador. They are known for eating stingrays, which are related to sharks.
Hammerhead Shark
Eats stingrays
Whale Shark
Eats phytoplankton
Fig. 4-1, p. 80

4. 4-1 What Is Biodiversity and Why Is It Important?
Concept 4-1 The biodiversity found in genes, species, ecosystems, and ecosystem processes is vital to sustaining life on earth.

5. Biodiversity Is a Crucial Part of the Earth’s Natural Capital (1)
Biological diversity, ___________________, is the… ________________ of earth’s species, the genes that they contain, and the ecosystems in which they live
Species: set of individuals who can mate and produce ___________________ offspring
So far biologists have identified ________________ species…we think that there are many more unidentified species in the ___________________ and ____________
biodiversity
variety
fertile
1.9 million
rainforests
oceans

6. Biodiversity Is a Crucial Part of the Earth’s Natural Capital (2)
There are four major components of biodiversity…
Species diversity – variety of species
Genetic diversity – enables life on earth to adapt and survive dramatic _____________________ changes
Ecosystem diversity – variety of _______________ or regions with distinct climates/species
Functional diversity – variety of process such as _________________ and _________________...that affect food webs
environmental
biomes
energy flow
matter cycling

7. Genetic Diversity The variety of genetic material within a
Functional Diversity The biological and chemical processes such as energy flow and matter recycling needed for the survival of species, communities, and ecosystems.
Ecological Diversity The variety of terrestrial and aquatic ecosystems found
in an area or on the earth.
Solar energy
Chemical nutrients (carbon dioxide, oxygen, nitrogen, minerals)
Heat
Heat
Heat
Decomposers (bacteria, fungi)
Producers (plants)
Consumers (plant eaters, meat eaters)
Heat
Heat
Figure 4.2: Natural capital.
This diagram illustrates the major components of the earth’s biodiversity—one of the earth’s most important renewable resources and a key component of the planet’s natural capital (see Figure 1-4, p. 9). See an animation based on this figure at CengageNOW. Question: What role do you play in such degradation?
Genetic Diversity The variety of genetic material within a
species or a population.
Species Diversity The number and abundance of species present in different communities.
Fig. 4-2, p. 82

8. Coastal mountain ranges Mississippi River Valley
Variety of Terrestrial Biomes
Denver
Baltimore
San Francisco
Las Vegas
St. Louis
Coastal mountain ranges
Sierra Nevada
Great American Desert
Rocky Mountains
Great Plains
Mississippi River Valley
Appalachian Mountains
Figure 4.5: The major biomes found along the 39th parallel across the United States are shown in this diagram. The differences in tree and other plant species reflect changes in climate, mainly differences in average annual precipitation and temperature.
Coastal chaparral
and scrub
Coniferous forest
Desert
Coniferous forest
Prairie grassland
Deciduous forest
Fig. 4-5, p. 84

9. Classifying Homo Sapiens
Classification
system to help
scientists study
biodiversity
Figure 2 This diagram illustrates the taxonomic classification of the latest human species, Homo sapiens sapiens.
Supplement 5, Fig. 2, p. S19

10. Edward O. Wilson First scientist to use the term biodiversity
in a research paper
Long career studying ___________ diversity
Worked to develop the theory of ___________ biogeography…which deals with how island biodiversity is affected by the ________ and _____________ of the island
insect
island
Figure 4.B: Edward O. Wilson.
size
location
Fig. 4-B, p. 85

11. Science Focus: Have You Thanked the Insects Today?
Bad rep: sting us, bite us, spread disease, eat our food, invade plants
_________________________: lets flowering plants reproduce sexually
Free pest control: insects eat ____________ insects
We need insects more than they need us
Pollination
other

12. Importance of Insects
Figure 4.A: Importance of insects: The monarch butterfly, like bees and numerous other insects, feeds on pollen in a flower (left), and pollinates flowering plants that serve as food for many plant eaters, including humans. The praying mantis, which is eating a house cricket (right), and many other insect species help to control the populations of most of the insect species we classify as pests.
Monarch butterfly pollinating a flower as it feeds
Praying mantis feeding on a cricket
Fig. 4-A, p. 83

13. 4-2 How Does the Earth’s Life Change Over Time?
Concept 4-2A The scientific theory of evolution explains how life on earth changes over time through changes in the genes of populations.
Concept 4-2B Populations evolve when genes mutate and give some individuals genetic traits that enhance their abilities to survive and to produce offspring with these traits (natural selection).

14. Biological Evolution by Natural Selection Explains How Life Changes over Time (1)
Fossils…_______________ or ________________ replicas of skeletons, bones, teeth, shells, leaves, seeds or _______________ of such items
Physical evidence of ____________ organisms
Reveal what their external structures looked like
Fossil record: entire _________of fossil evidence
Uneven and incomplete… we probably only have fossils of 1% of all species that lived on earth
mineralized
petrified
impressions
ancient
body

15. Fossilized Skeleton of an Herbivore that Lived during the Cenozoic Era
Figure 4.6: This fossilized skeleton is the mineralized remains of an herbivore that lived during the Cenozoic era from 26 to 66 million years ago.
Fig. 4-6, p. 86

16. Biological Evolution by Natural Selection Explains How Life Changes over Time (2)
Biological evolution: how earth’s life changes over time through changes in the __________________ characteristics of populations
First person who attempted to explain the process behind evolution was ______________ ______________...published his explanation in 1859: On Origin of Species by Means of Natural Selection
Alfred _______________ also studied natural selection at the time and derived similar conclusions
Natural selection: individuals with certain __________ are more likely to survive and _______________ under a certain set of _____________________ conditions
genetic
Charles
Darwin
Wallace
traits
reproduce
environmental

17. Evolution of Life on Earth
Theory of evolution
states that all species
descend from earlier
_______________
species
Basically, life comes
from life
ancestral
Figure 1 This diagram provides an overview of the evolution of life on the earth into six major kingdoms of species as a result of natural selection.
Supplement 5, Fig. 2, p. S18

18. Evolution by Natural Selection Works through Mutations and Adaptations (1)
________________ evolve by becoming genetically different
Can an individual evolve during its lifetime?
Ex: If a human runs every day will he/she be able to run as fast as a cheetah?
Genetic variations
First step in biological evolution
Occurs through _______________ in reproductive cells…that get passed along ________________
Mutations: random changes in ________ molecules
Populations No
mutations
to offspring
DNA

19. Evolution by Natural Selection Works through Mutations and Adaptations (2)
Natural selection: favors some individuals over others
Second step in biological evolution
Adaptation – any heritable trait that gives you a survival/reproductive _________________
Adaptations may lead to differential reproduction….enables individuals with the trait to produce more ___________________ offspring
advantage
surviving

20. Evolution by Natural Selection
Genetic resistance: ability of one or more members of a population to resist a _________________ designed to kill it
chemical
Figure 4.7: Evolution by natural selection. (a) A population of bacteria is exposed to an antibiotic, which (b) kills all individuals except those possessing a trait that makes them resistant to the drug. (c) The resistant bacteria multiply and eventually (d) replace all or most of the nonresistant bacteria.
Fig. 4-7, p. 87

21. Case Study: How Did Humans Become Such a Powerful Species?
Human adaptations…
Strong opposable thumbs
Walk upright
Complex brain

22. Adaptation through Natural Selection Has Limits
Adaptive genetic traits must _____________change in the environmental conditions
Reproductive capacity
Species that reproduce rapidly and in large numbers are _______________ able to adapt
precede
better

23. Three Common Myths about Evolution through Natural Selection
“Survival of the fittest” is not “survival of the strongest”
Organisms do not develop traits out of need or want
No grand plan of nature for perfect adaptation

24. Review Questions
What are the four major components of biodiversity demonstrated in this figure?
Ecosystem
diversity
functional
diversity
Species
diversity
genetic
diversity

25. Review Questions Place the following concepts in the correct order…
populations evolve
genes mutate
individuals are selected 3 1 2