The Age of Things:Sticks, Stones and the Universe

Molecular Dating and the Many Kinds of Mammals

http://cfcp.uchicago.edu/~mmhedman/compton1.html

Proconsul

WARNING! Astrophysicist talking about Mammalian Phylogeny!

Monotremes Marsupials

Non-Placental Mammals

Rodentia

Lagomorpha

Chiroptera

Carnivora

Primates

Cetacea

Atriodactyla

Perissodactlya

Xenarthra

Proboscidea

Sirenia

Hyracoidea

PholidotaDermoptera Tubilentata

Insectivora

MacroscelideaScandentia

Fossil Records of the Different Orders

Relationships between the orders derived from morphological characteristics

Perhaps orders arose rapidly when the dinosaurs died out

Molecular Data

Hedgehog TGCCAATTCCGTTCTGTTGTGAGAATGGACTACATGGTGTTCTTCAGCTTSloth TGCCAAATTAGTTCCGTCATGAGAATGGACTACATGGTCTACTTCAGTTT

Sirenian TGCCAATTCCGTTCCGTTATGAAGATGGACTACATGGTCTACTTCAGCTTElephant TGCCAATTCCGTTCCGTTATGAGGATGGACTACATGGTCTACTTCAGCTTAardvark TGCCAATTCCGTTCCGTTATGAGGATGGACTACATGGTCTACTTCAGCTT

Mouse TGCCACTTCCGTTCCGTGGTCAGTTTGGATTACATGGTCTTCTTCAGCTTRabbit TGCAAATTCGATTCTGTTATACCCATGGAATACATGGTCTTCTTTAGCTTHuman TGCCAATTTGTTTCCGTCATGAGAATGGTCTACATGGTATACTTCAGCTT

Flying Fox TGCCAATTCCGTTCTGTCATAAAGATGGACTACATGGTCTATTTCAGCTTWhale TGCCAATTCCGTTCCGTCATGAGGATGGACTACATGGTCTACTTCAGCTT

Pig TGCCAGTTCCGTCATGAGGATGGACTGGACTACATGGTCTACTTCAGCTTHorse TGCCAATTCCGTTCTGTTGTGAGCATGGACTACATGGTCTACTTCAGCTTCat TGCCAGTTCCGTTCTGTCATGACGATGGACTACATGGTCTACTTCAGCTT

Chimp Gorilla OrangutanHuman 1.24% 1.62% 3.08%Chimp 1.63% 3.12%Gorilla 3.09%

Human Chimp Gorilla Orangutan

All animals do not accumulate mutations at the same rate

W X Y Z

30 Mutations 10 Mutations 10 Mutations30 Mutations

5 Mutations5 Mutations

Time 1

Time 0

Time 2

W X Y Z

30 Mutations 10 Mutations 10 Mutations30 Mutations

5 Mutations5 Mutations

Time 1

Time 0

Time 2

X Y ZW 40 50 70X 30 50Y 40

W X Y Z

30 Mutations 10 Mutations 10 Mutations30 Mutations

5 Mutations5 Mutations

Time 1

Time 0

Time 2

X Y ZW 40 50 70X 30 50Y 40

W X Y Z

30 Mutations 10 Mutations 10 Mutations30 Mutations

5 Mutations5 Mutations

Time 1

Time 0

Time 2

X Y ZW 40 50 70X 30 50Y 40

W X Y Z

30 Mutations 10 Mutations 10 Mutations30 Mutations

5 Mutations5 Mutations

Time 1

Time 0

Time 2

X Y ZW 40 50 70X 30 50Y 40

W X Y Z

30 Mutations 10 Mutations 10 Mutations30 Mutations

5 Mutations5 Mutations

Time 1

Time 0

Time 2

X Y ZW 40 50 70X 30 50Y 40

Accumulates More Mutations

W X Y Z

30 Mutations 10 Mutations 10 Mutations30 Mutations

5 Mutations5 Mutations

Time 1

Time 0

Time 2

X Y ZW 40 50 70X 30 50Y 40

Accumulates More Mutations

W X Y Z

30 Mutations 10 Mutations 10 Mutations30 Mutations

5 Mutations5 Mutations

Time 1

Time 0

Time 2

X Y ZW 40 50 70X 30 50Y 40

Tree Based on Morphological Characters Tree Based on Molecular Characters

Afrotheria

Euarchonotoglires

Xenartha

Laurasiatheria

Human Chimp Gorilla Orangutan

1%

2%

3%

Sivapithecus

Proconsul

15

10

5

Mil

lio

ns

of

year

s ag

o

Calibrating the molecular clock

ProconsulSivapithecus

W X Y Z

30 Mutations 10 Mutations 10 Mutations30 Mutations

5 Mutations5 Mutations

Time 1

Time 0

Time 2

X Y ZW 40 50 70X 30 50Y 40

W X Y Z

30 Mutations 10 Mutations 10 Mutations30 Mutations

5 Mutations5 Mutations

Time 1

Time 0

Time 2

X Y ZW 40 50 70X 30 50Y 40

A simpler problem: Flipping Coins

Probability of getting five heads, given the number of Coin Flips

A simpler problem: Flipping Coins

Probability of getting five heads, given the number of Coin Flips

Assumed Probability of each number of Coin Flips

A simpler problem: Flipping Coins

Probability of getting five heads, given the number of Coin Flips

Assumed Probability of each number of Coin Flips

Likelihood the coin was flipped a given

number of times

Eutherians

120 Million Years Ago

Eutherians

Afrotheria

Xenarthra and others

105 Million Years Ago

Afrotheria

Xenarthra

Euarchontoglires

Laurasiatheria

?

90 Million Years Ago

Next Time

Meteorites and the Age of the Solar System