2015 sf exploratorium lecture: "corn: diversity and origins"

Corn: Diversity and Origins

Jeffrey Ross-Ibarra @jrossibarra • www.rilab.org University of California, Davis

Photo: Jason Wallace

tassel (male)

ear (female)

Photo: U. Nebraska-Lincoln

corn (maize)

tassel (male)

ear (female)Photo: OllieMartin

Photo: U. Nebraska-Lincoln

corn (maize)

tassel (male)

ear (female)Photo: OllieMartin

Photo: U. Nebraska-Lincoln

Photo: © HD WIlson

corn (maize)

Photo: Rosana Prada

Photo: https://www.flickr.com/photos/croptrust/

Photo: https://www.flickr.com/photos/dandelion-and-burdock/

ACTG

Photo: Michael Neugebauer

1.2% DNA difference

Photo: USDA

Photo: Michael Neugebauer

1.2% DNA difference1.6% DNA difference

Photo: USDA

Original DNA

Mutation

Original DNA

Original DNA Transposon

Barbara McClintock 1902-1992

Original DNA Transposon

Barbara McClintock 1902-1992

Original DNA Transposon

Photo: Damon Lisch

purple:no transposon

Photo: Damon Lisch

purple:no transposon

yellow:transposon

inserted

Photo: Damon Lisch

purple:no transposon

yellow:transposon

inserted

spots:transposon jumps

Photo: Damon Lisch

purple:no transposon

yellow:transposon

inserted

spots:transposon jumps

Photo: Damon Lisch

no transposon

Photos: Cold Spring Harbor Laboratory Press

transposon

A TG AC T

A TG GC T

A CG GC T

A TG GC T

A TG AC T

A TG GC T

A CG GC T

A TG GC T

A TG AC T

A TG GC T

A CG GC T

A TG GC T

A TG AC T

A TG GC T

A CG GC T

A TG GC T

A TG AC T

A CG GC T

A TG AC T

A TG GC T

A CG AC T

A TG AC T

A CG AC T

A CG GC T

A CG GC T

A TG GC T

traditional (landrace)

A CG GC T

A CG GC T

modern industrial corn

A CG GC T

A CG GC T

A CG GC T

A CG GC T

modern industrial corn

A CG GC T

A CG GC T

A TG AC T

A TG AC T

Modern Industrial Corn

A CG GC T

A CG GC T

A TG AC T

A TG AC T

A CG GC T

A TG AC T

Modern Industrial Corn

A CG GC T

A CG GC T

A TG AC T

A TG AC T

A CG GC T

A TG AC T

A CG GC T

A TG AC T

Modern Industrial Corn

A CG GC T

A CG GC T

A TG AC T

A TG AC T

A CG GC T

A TG AC T

Modern Industrial Corn

Beadle 1979 Field Museum of Natural History Bulletin Meyerowitz 1994 Current Biology

Duvick et al. 1999 US 6639132 B1

maize origins

Tripsacum extinct maizeF1F1

teosinte Zea mays ssp. parviglumis

maize Zea mays ssp. mays

George Beadle

Meyerowitz 1994 Current Biology Duvick et al. 1999 US 6639132 B1

maize origins

Tripsacum extinct maizeF1F1

teosinte Zea mays ssp. parviglumis

maize Zea mays ssp. mays

teosinte parviglumis

teosinte mexicana

modern corn

Matsuoka 2002 PNAS

teosinte parviglumis

teosinte mexicana

modern corn

Matsuoka 2002 PNAS

Photos: Matt Hufford, Brandon Gaut, John Doebley

teosinte teosinte

modern corn

modern corn

teosinte

modern corn

teosinte

modern corn

reconstructed ancestral corn

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modern corn

reconstructed ancestral corn

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Highland Route

Highland Route

Pacific Route

Photo: Moenkopi Legacy Inn & Suites

Highland Route

Pacific Route

Highland Route

Pacific Route

modern Chapalote

modern Palomero

Highland Route

Pacific Route

modern Chapalote

modern Palomero

Tularosa Cave

Highland Route

Pacific Route

3,000 yrs

modern Chapalote

modern Palomero

Highland Route

Pacific Route

3,000 yrs

modern Chapalote

modern Palomero

2,000 yrs 1,000 yrs

Highland Route

Pacific Route

3,000 yrs

modern Chapalote

modern Palomero

700 yrs2,000 yrs 1,000 yrs

01010

0010 01011 01111

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