Stromatolites: layers of rock with fossils

Origin of Life

• Big Bang Theory: formation of the universe (20 billion years ago=bya)

• Earth formed 4.5 bya

• First atmosphere: hydrogen, water vapor,nitrogen, methane, ammonia

• What is missing??

FREE OXYGEN

Core

Crust

Miller Experiment

InorganicMolecules

Organic Molecules

(hydrogen, watervapor,nitrogen, ammonia)

(carbohydrates=sugars, Lipids=fats, proteins,DNA)

Electricity

No electricity 3.5 bya, so what could cause a spark?

First life on earth 3.5 bya, prokaryotic cells

Prokaryotic cells Eukaryotic cells (1.5 bya)

Miller Experiment: the origin of life

Plate Tectonics

Plate Tectonics

• What is it called, when plates move against each other?

• An earthquake!• What is it called where the plates meet?• Earthquake fault• What earthquake fault do we live near?• San Andreas Fault• Earthquake Kit??

Continental Drift

Continental Drift

Pangaea:

continents in one land mass

Laurasia:

N. AmericaEuropeAsia

Gondwana:

Africa, S. AmericaAustralia, Antarctica,India

•Quaternary: modern man•Tertiary: radiation of mammals__________________________________•Cretaceous: mass extinction of dinosaurs•Jurassic: dinosaurs dominant•Triassic: first dinosaurs__________________________________•Permian: mass extinction of marine life•Carboniferous: first reptiles•Devonian: first amphibians•Ordovician: first fishes•Cambrian: marine life abundant•Precambrian: first life on earth

Cenozoic

Mesozoic

Paleozoic

Past vs. Current Extinction

Past

•Slow•Natural Causes•Extinction with replacement

Current

•Fast•Human Causes•Extinction without replacement

Taxonomy

• Linnaeus/binomial name (Genus species)• Humans = Homo sapiens• Kingdom, Phylum, Class, Order, Family,

Genus, Species• Homology = similarity in structure due to a

common ancestor• Analogy = similarity in function not due to

a common ancestor• DNA comparison

Homologous Structures

Schools of Taxonomy

• Phenetics: looks for similarity and differences whether homology or analogy

• Phylogenetics: use homologies to map evolutionary relationship

• Cladistics

Clade = evolutionary branch

Cladogram = series of dichotomous forks