1. Chapter 4 – The organization of life
Section 1 – Ecosystems: Everything is Connected

2. Defining an Ecosystem
Ecosystem: Communities of organisms and their surrounding environment
- oak forest or a coral reef
Ecosystems are connected
a. Do not have clear boundaries
b. Things move from one ecosystem to another
- Pollen can blow from a forest into a field
- Soil can wash from a mountain into a lake

3. Ecology
Ecology: the branch of biology that deals with the relations of organisms to one another and to their physical surroundings.

4. The Components of an Ecosystem
- Ecosystems need five basic components to survive:
1. energy (most comes from the sun)
2. mineral nutrients
3. water
4. oxygen
5. living organisms.
- If one part of the ecosystem is destroyed or changes, the entire system is affected

5. Biotic and Abiotic Factors
- environmental factors that are living or once living organisms OR materials that come from organisms
- plants, animals, dead organisms, and their waste products
- Abiotic factors
- environmental factors that never were living organisms
- air, water, rocks, and temperature, etc.

6. Levels of Ecological Organization
Pick-up Figure 4, page 95

7. Ecologists organize life into categories
Organism: Living things that can carry out life processes independently.
-You are an organism, as is an ant, ivy plant, and each of the bacteria living in your intestines.
- Every organism is a member of a species.
-Species are groups of organisms that are closely related and can mate to produce fertile offspring. (Mating pair)

8. Ecologists organize life into categories
- Members of a species may not all live in the same place. Field mice in Maine will not interact with field mice in Texas
- Populations
- groups of organisms of the same species that live in a specific geographical area and interbreed.
- All the field mice in a corn field make up a population of field mice.

9. Ecologists organize life into categories
- Members of a population usually breed with one another rather than with members of other populations
- Bison will usually mate with another member of the same herd not other a member from another herd

10. Ecologists organize life into categories
Communities: Groups of various species that live in the same habitat and interact with each other
- Every population is part of a community
- The most obvious difference between communities is the types of species they have.
- Land communities are often dominated by plants species
- The plants determine what other organisms can live in that community

11. Ecologists organize life into categories
Habitat: Places where an organism usually lives
- Habitats have specific characteristics that the organisms living there need to survive
- If any of these factors change, the habitat changes
- Organisms tend to be very well suited to their natural habitats
- animals and plants usually cannot survive for long periods of time away from their natural habitat

12. Ecologists organize life into categories
Ecosystem: Communities of organisms and their surrounding environment
Biome: a large region with a similar climate and organisms
Biosphere: the regions of the surface, atmosphere, and hydrosphere of the earth occupied by life.

13. Critical Factors

14. Organism Research Project
Pick an Organism and research the following information about the organism:
Common Name, Scientific Name, Name of a group of your organism (ex: Group of lion = Pride, sault, or troop)
Other populations that interact with this species
Detailed description of natural Habitat (include some specific biotic and abiotic factors in description)
Regional location (be specific as possible) and Biome (include climate details) the organism is primarily located
Create a mini-poster with all of this information. Include a colored drawing of your organism in an example of it’s habitat.

15. Chapter 4 – The organization of life
-Turn in: Ecosystem Drawing and Organism Poster.
-Get a Evolution Note handout.
What do you think?
What are some adaptations organisms have to hunt prey? What are some ways organisms defend for themselves from hunters?
Chapter 4 – The organization of life
Section 2 - Evolution

16. Charles Darwin
- Charles Darwin observed that organisms in a population differ slightly from each other in form (structure), function, and behavior
- Some of these differences are hereditary (get passed from parent to offspring)
- He proposed the environment exerts a strong influence over which individuals survive to produce offspring
- Some are more likely to survive and reproduce than other individuals because of certain traits

17. Evolution by Natural Selection
- Natural selection: individuals that have favorable traits and are better adapted to their environment.
-They survive and reproduce more successfully than less- adapted individuals
- Darwin proposed that over many generations, natural selection causes the characteristics of populations to change
- Evolution: change in the characteristics of a population from one generation to the next. AKA “decent with modification”

18. Nature Selects
Pick-up Figure 8, page 99

19. Nature Selects
- Nature ‘selects’ for certain traits, such as sharper claws, because organisms with these traits are more likely to survive
- Over time, the population includes a greater and greater proportion of organisms with the beneficial trait
- As the populations of a given species change, so does the species.

20. Sickle Cell Anemia http://www.youtube.com/watch?v=1fN7rOwDyMQ
In the heterozygous condition, both alleles are expressed equally
Example: Sickle Cell Anemia in Humans
NS = some of each
SS = sickle cells
NN = normal cells
sick

21. Nature Selects
Adaptation: an inherited trait that increases an organism's chance of survival and reproduction in a certain environment
-Can be an Physical, Behavioral, or Physiological change that improves a population’s ability to
survive

22. Three Types of Adaptations
Physical Adaptations: some type of structural modification made to a part of the body.
Ex: webbed feet, sharp claws, fur.
Behavioral Adaptations: something an animal does (how it acts) usually in response to some type of external stimulus.
Ex: hibernation, mating dances, flying south for winter
Physiological Adaptations: the ability of the organism to perform special functions
Ex: venom production, temperature regulation, growth and development.

23. Darwin’s Four Premises
Overproduction – each species produces more offspring than will survive to maturity
Variation – individuals in a population have slightly different traits
Selection – individuals compete and the environment selects those with traits that help survival and reproduction
Adaptation of a Population/Successful Reproduction – beneficial traits become more common in the next generation

24. Coevolution
Coevolution: When two species evolve in response to long-term interactions with each other
- The Hawaiian honeycreeper has a long, curved beak to reach nectar at the base of a flower
- The flower has structures that ensure the bird gets some pollen on its head
- When the bird moves the next flower, some of the pollen will be transferred, helping the flower reproduce

25. Coevolution - The honeycreeper’s adaptation is a long, curved beak.
- The plant has two adaptations:
- 1. the sweet nectar to attract the birds
- 2. the flower structure that forces pollen onto the bird’s head when it sips nectar

26. Newt vs. Snake

27. Man Selects
Artificial selection :selective breeding of organisms, by humans, for specific desirable characteristics.
- Dogs have been bred for certain characteristics
- Sporting, Hunting, Herding, Terriers, Working, etc.
- Fruits, grains, and vegetables are also produced by artificial selection.
- Humans save seeds from the largest, and sweetest fruits
- Farmers direct the evolution of crop plants to produce larger, sweeter fruit

28. Evolution of Resistance
Resistance: the ability of an organism to tolerate a chemical or disease-causing agent
- An organism may be resistant to a chemical when it contains a gene that allows it to break down a chemical into harmless substances
- Humans promote (encourage) the evolution of resistant populations by trying to control pests and bacteria with chemicals.

29. Evolution and Resistance
Pesticide and Corn:
-A pesticide is sprayed on corn to kill grasshoppers, may kill most of the grasshoppers, but some develop resistance
- The hoppers that survive could have a gene that protects them from the pesticide
- These surviving insects pass on this resistant gene to their offspring
- Each time the corn is sprayed, more resistant grasshoppers enter the population
- Eventually the entire population will be resistant, making the pesticide useless

30. Pesticide Resistance
Pick-up Figure 11, page 101

31. Antibiotic Resistance Video
copeland-gma-interview-battle-flesh-eating- disease

32. Evidence for Evolution
Homologous Structures
Vestigial Structures
Biochemical Evidence

33. Homologous structures:
Similar Structures in Different species suggest a common ancestor

35. Homologous Structures
-Show descent with modification
-Traits that are similar between different species have been inherited from a common ancestor

36. Vestigial Structures
traces of structures from ancestral species that serve no current useful function ex. Pelvic Bones in whales, appendix in Humans

37. Whale pelvic bones are vestigial

39. Example: Hand bones in a manatee

40. Comparing DNA
Biochemical Evidence: Shows DNA similarities and relatedness
The more DNA species have in common, the more closely related they are
Ex. Human and Chimp are about 98% same DNA

41. Convergent vs. Divergent
Convergent evolution
Different species produce similar adaptations
Divergent evolution
Similar species produce different adaptations

44. Darwin’s Finches