I. Theory of Evolution

• Predict what the early atmosphere and environment of the Earth were like.

Oparin’s Theory

• “The origins of all life on Earth were in nonliving chemical substances which spontaneously formed in Earth's early atmosphere and combined to make more complex chemicals until living cells were formed.”

Miller/Urey Experiment

Miller/Urey Experiment

• Produced amino acids by passing sparks through a mixture of hydrogen, methane, ammonia, and water.

• This suggested that simple compounds found on Earth could have combined to form organic compounds needed for life.

Lamarck’s Theory of Evolution

• “By selective use or disuse of organs, organisms acquired or lost certain traits during their lifetime. These traits could then be passed on to their offspring. Over time, this process led to change in a species.”

Charles Darwin

Natural Selection

• Individuals that are better suited to their environment survive and reproduce most successfully. (Survival of the fittest)

• Passing on of genes by the best adapted organisms.

• This cannot be seen directly, only over many successive generations!

What other evidence is there?

• Skulls

• Bird wings/beaks

• Human appendix

• Mammalian embryos

• DNA fingerprints

Artificial Selection

• The breeding of plants and animals based on a specific characteristic.

• Examples:– Variety of dogs– Cows with high milk production– Pigs with long backs– Plants that are disease resistant– Plants that yield a lot of fruit or vegetables

Patterns of Evolution

• Macroevolution refers to the large-scale evolutionary patterns and processes that occur over long periods of time.

1. Extinction: Species died out

2. Adaptive Radiation: a single species or a small group of species has evolved through natural selection and other processes, into diverse forms that live in different ways

ex. Darwin’s finches

3. Convergent Evolution: unrelated organisms come to resemble one another

ex. Fish and aquatic mammals

4. Coevolution: when two species evolve in response to changes in each other over time

ex. Pollinating insects and flowers

plants producing poisons

5. Gradualism: organisms change gradually over time.

6. Punctuated equilibrium: a rapid change in a species

7.Developmental Genes: changes in genes could produce transformations in body size and shape

ex. Turning on or off genes

II. Classification of Organisms

• Taxonomy: classification and naming of living things

• Binomial Nomenclature: use of two names to identify an organism Genus species

Ex. Homo sapien

Musca domestica (house fly)

Taraxacum officinale (dandelion)

Linnaeus’s Hierarchial System of Classification

• Kingdom

• Phylum

• Class

• Order

• Family

• Genus

• Species

The 3 Domains• Bacteria

– Unicellular and prokaryotic– Corresponds with the kingdom Eubacteria

• Archaea– Unicellular and prokaryotic– Live in very extreme environments– Many can survive without oxygen– Corresponds with the kingdom Archaebacteria

• Eukarya– Eukaryotic organisms– Corresponds with the Protista, Fungi, Plantae, and

Animalia kingdoms

The 5 Kingdoms• Eubacteria

• Archaebacteria

• Protista

• Fungi

• Plantae

• Animalia