Early Evolution

Wolves to Different Dog Breeding

​man walking with 4 limbs to modern standing-straight man

4.6 billion years ago

Earth has NO OXYGEN at all!

therefore, NO life

-bacteria can live with or without oxygen(anaerobic)

-evolved into a photosynthetic one

-become anaerobic photosynthetic bacteria

• How did life arise on Earth?

• cyanobacteria- prokaryotes that are photosynthetic

• first(primitive) organisms- anaerobic prokaryotes

• the anaerobic photosynthetic bacteria(cyanobacteria) started producing oxygen to the earth's atmosphere

suggested the young Earth could have life through the presence of basic organic molecules(amino acids)

-that amino acids could develop from inorganic such as methane, water, carbon, sulfur, etc

​Miller-Urey's Experiment

1. unicellular prokaryotes
2. photosynthetic prokaryotes
3. unicellular eukaryotes
4. multicellular eukaryotes
5. very small plants and animals

How many species is now extinct?

99%

What is extinct means?

stop existing

-fossil record
-biographical(species distribution)
-anatomical comparison (homologous/analogous bone structures)

​-embryology
-biochemistry(DNA comparison)

​What are the evidences of evolution?

Create a Cause-and-Effect Model
Summarize the evidence of evolution, using these slides.