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Walter Alvarez and Roland Saekow and Planetary Science University of , Berkeley

Earth history goes back almost exactly 106 times as far as

Human History: 5,000 years Earth history: 5,000 million years

Gubbio, a medieval town in Umbria Gubbio, a medieval town in Umbria

T K Only 3 species of small forams survive

1 mm base Tertiary (T) top Cretaceous (K)

Many species of forams, including large ones 1 mm

The Berkeley Theory — Impact at the KT boundary

Donald E. Davis Evidence for the KT impact

KT impact spherule from the Pacific Ocean

KT shocked quartz from Montana The buried crater at Chicxulub (Yucatán Peninsula)

Diameter 170 km (largest on Earth in last 1.8 billion years)

Imaged by gravity David Christian Macquarie University Sydney

Maps of Time, 2004, University of California Press Earth and Planetary Science 51 : Cosmos, Earth, , Humanity Cosmic History

Big Bang 10 billion 5 billion Today Years ago Years ago 4.567 Earth History billion years

Cosmic History

Big Bang 10 billion 5 billion Today Years ago Years ago About 4 Life History billion years 4.567 Earth History billion years

Cosmic History

Big Bang 10 billion 5 billion Today Years ago Years ago About 5 Human Million years (Before About 4 Life History writing) billion years 4.567 Earth History billion years

Cosmic History

Big Bang 10 billion 5 billion Today Years ago Years ago * About 5 Human thousand years History About 5 Human million years Prehistory (Before About 4 Life History writing) billion years 4.567 Earth History billion years

Cosmic History

Big Bang 10 billion 5 billion Today Years ago Years ago Earth, Solar system formed Modern humans extinction Invention World War II Last year Universe formed of writing in Big Bang

1010 yr 105 yr 100 yr ago ago ago Cambrian explosion, Abundant fossils

Earth, Solar system formed Modern Modern Dinosaur humans extinction Early Invention World humans War II Last year Universe formed of writing in Big Bang

1010 yr 105 yr 100 yr ago ago ago

Walter Alvarez and Roland Saekow Earth and Planetary Science University of California, Berkeley

Video Title video Partner Title partner Name Title Company Customer Title customer Name Title Company Announcement Title announcing Robert Butler, Univ. Arizona Robert Butler, Univ. Arizona

Touareg Festival at Ghat, 1969 The Sahara, verdant 8,000 years ago, is now a desert

Ghat Nile

Sahel Stone-age art shows animals who lived in the now-hyperarid desert

Libyan Sahara Bedrock grooved by glaciers Algerian Sahara Bedrock grooved by glaciers Algerian in the Ordovician, Sahara about 450 million years ago An Ordovician fossil ice stream in 450 million years old

Mega-scale glacial lineations Ghat due to a fast-flowing ice stream

10 km Moreau et al., Geology, Sept 2005 A modern ice stream in Antarctica: Byrd Glacier

The Rodinia Supercontinent, 700 million years ago The Rodinia Supercontinent, 700 million years ago The assembly of Gondwanaland

California, 606± for scale 2 Ma The assembly of Gondwanaland Ghat demo demo James Ogg Adam Lugowski