1. Species Change Over Time

2. CH 6 Objectives
Identify early ideas and observations on evolution
Explain how Darwin developed his theory of natural selection
Identify Darwin’s 4 principles of natural selection
Describe how new species can form from previous species

3. Essential Questions and Understandings
What is evolution and who contributed to the modern theory of evolution?
Compare and Contrast Artificial and Natural Selection
What are Darwin’s 4 principles and how do they lead to evolution?
What is speciation?
How can isolation of a group of individuals lead to a new species?

4. Evolution is defined as change over time
It is the result of changes in the genetic material that are passed from generation to generation
Organisms use adaptations to have a better chance of surviving and reproducing

5. History
Lamarck was on of the first scientists to suggest the idea of change over the lifetime of an organism (Giraffes Necks)
Darwin studied plant and animal species on the Galapagos Islands (178 islands)
He noticed that species were different from island to island
Looked at adaptations to certain environments
Looked at finches and their feeding behaviors

6. Artificial Selection
When people (breeders) produce new varieties of animals over time
Select a certain desired trait
Breed two animals displaying that trait
The result is offspring displaying the trait

7. Darwin proposed the same thing was happening naturally in the animal and plant world
He based his ideas on 4 principles:
Overproduction: When a species produces more offspring than can live in the environment
Variation: mutations that naturally occur in the genetic material
Adaptation: any inherited trait that gives an organisms an advantage to survive
Selection: if a trait helps an organism survive to reproduce, the trait has been “selected”
Natural Selection

8. Speciation The evolution of new species from an existing organism
Can occur when the environment changes dramatically such as a volcanic eruption
New species can also occur when the environment changes gradually

9. Formation of New Species due to Isolation
Example from a population of Cichlids (fish)
Water level is low, one species lives in a lake
Level rises filling shoreline, population spreads throughout the lake
Level falls, isolating the fish from each other
New species development that are more successful in their environment

10. Isolation Can Lead to New Species
Scientist believe that Isolation is essential to speciation
Isolation can occur due to geographic changes such as mountains building up
Cases caused by isolation have led to the great level of biodiversity on Earth

11. CH 7
Classification of Living Things

12. CH 7 Objectives Explain why scientists classify living things
Describe evidence scientist use to classify organisms
Explain how scientific names are determined and give examples
Use the 7 levels of classification to identify an organism
Describe organisms found in each of the current 6 kingdom system of classification
Describe the 3 domains
Describe how dichotomous keys can be used to identify organisms
Utilize a dichotomous key to identify common household objects

13. Essential Questions and Understanding
Understand how scientist study biological relationships to classify living organisms
How has our classification system changed over time?
Describe how we give organisms scientific names and give and example.
Use a dichotomous key to classify organisms correctly
Identify characteristics of organisms found in the 6 kingdoms

14. 1600’s: organisms were classified based on appearance and behavior
PROBLEM: Can be deceiving, not universal (i.e. they could not ALL agree on a system for naming organisms)
1700’s: 2 Kingdoms (Plant and Animal)
Linnaeus set a standard 2 name system for each animal (Genus species)
Linnaeus developed a system for naming species and organizing them into groups 1866: 3 Kingdom Sytem (plant, animal, protista)
20th Century: Started using DNA and genes to classify related species
1925: 2 Kingdoms (Prokaryota & Eukaryota)
1938: 4 Kingdoms (Monera, Protoctista, Plantae, Animalia)
1969: 5 Kingdom System (Monera, Protista, Plantae, Fungi, Animalia)
1977: Current 6 Kingdom System
2000’s:???? 7 Kingdoms???? No Kingdoms??? Domains??

15. Classification
Classification is the process of arranging organisms into groups based on similarities
Taxonomy: science of naming and classifying organisms
To classify organisms scientists use similarities and differences among species
A classification system (such as one found in a field guide can help you identify unfamiliar organisms
A taxon is a group of organisms that share certain traits based on shared ancestors.
Not All organisms that look alike are closely related

16. Binomial Nomenclature
Each organism has a 2 part name
Scientific name
Written in Latin and Greek
Genus species
Genus: a group of species with similar characteristics
Species: the specific name for the organism (contains the least number of organisms)
EX) Homo sapiens (human), Aubrieta gracilis (flower), Chameleo gracilis (chameleon), Mammillaria gracilis (cactus)

17. 7 Levels of Classification to Name a Species
Each level is more specific than the last
Kings Play Chess On Fat Green Stools
Kingdom
Phylum
Class
Order
Family
Genus
Species

18. Dichotomous Keys
Asks a series of questions that can be answered in only two ways.
Each answer leads to another question until you identify the organism

19. KEY TO THE CRITTERS ON BEBONK
1. Has 1 hair………………………………………………..2
Has 2 hairs………………………………………………4
2. Has a belly button…………………………………BIP
Has no belly button………………………………3
3. Has 2 legs………………………………………………GLIP
Has 4 legs……………………………………………FOOP
4. Has arms…………………………………………….GLOP
Has no arms……………………………………….NOP

21. Multicellular
Live on water and land
Obtain energy from sunlight
Have a nucleus, cell wall, chloroplast
EX) grass, trees, moss
Kingdom Plantae

22. Kingdom Animalia
Multicellular
Live on water and land
Obtain energy by eating food
Have a nucleus, no cell wall, no chloroplast
Have the ability to move
EX) human, elephant dog, fish bugs

23. Kingdom Protista
Most are unicellular
Nucleus
Have the ability to move
Some eat like animals
Some get energy from sunlight
EX) Sea weed, Kelp, Euglena

24. Takes nutrients from environment Rooted in one place Have cell walls
Kingdom Fungi
Takes nutrients from environment
Rooted in one place
Have cell walls
Act as decomposers
EX) Mushroom, yeast, molds

25. Live in extreme environments-high heat, high salt, high sulfer
Kingdom Archaea
No Nuclei
Live in extreme environments-high heat, high salt, high sulfer
EX) Methanococcoides burtonii

26. Reproduce by dividing in two Can move EX) E. Coli
Kingdom Bacteria
Unicellular
No Nuclei
Reproduce by dividing in two
Can move
EX) E. Coli