And has not such a Story from of Old
Down Man's successive generations roll'd
Of such a clod of saturated Earth
Cast by the Maker into Human mold?
--Omar Khayyam, Rubaiyat, FitzGerald, Fifth Edition

Audesirk, Audesirk & Byers Part of chapter 17, selections from Chapters 18 & 25

Today's musical selection
Irish Rovers - The unicorn song

History of life on Earth

molten rock solidifies 3.8 bya
Box, scientific inquiry, How do we know how old a fossil is?
40K -> 40Ar, bubbles out of molten rock, trapped in solid rock,
1.25 billion yr half life


Numbers (e.g. -570-) are million years ago

Table 17-1
(Useful to present in reverse, start at the beginning)

Precambrian 4.6 Earth

chemical evolution
biological evolution
RNA as hereditary molecule
Then DNA

very first life 3.5 1st fossils
these would have been anaerobic heterotrophs
3.5 Photosynthesis -> oxygen begins 2,200

2000 (million years ago = 2 billion) eukaryotes
diploidy and sexual reproduction around that time
then they get symbiotes, first mitochondria then chloroplasts
(endosymbiosis was covered in cell lecture)
1200 1st multicellular eukaryotes

O2 high to O3
(ozone, blocks UV, 260 nm damages DNA, 280 damages protein, now freon depletes)



Cambrian explosion (many species formed)

Figure 17-10
Mass extinctions

Coal deposited before and after Carboniferous, but Carboniferous is central.
Frequently flooded swamps with vascular plantscaused "reducing" conditions.
Petroleum from microscopic organism deposits often found near deposits of foraminiferans.
(Also associated with Carboniferous but quite extensive time span.)

Figure 17-11
Plate tectonics (actually not widely understood until the 1970's)
Pangaea, continental drift

Permian extinction, lose ocean habitat
Pangaea formed


Triassic 1st dinosaurs
Pangaea breakup
End of Triassic, mass extinctions, possibly global warming


Jurassic Dinosaurs, 1st birds
mammals flower plant
(Hard to imagine mammals would surpass dinosaurs, but adaptations to survival)


Cretaceous flowering plants
Mass extinctions - meteorite iridium -2.5 tril.tons 11km

- 65 million -



adaptive radiation of mammals & birds
...(other epochs)...


Quarternary Pleistocene (epoch) 4 ice ages
to MO, Ohio R.
mammoths die out
first Homo


Figure 17-12
Primitive primates (prosimians) lemurs, tree shrews
New world monkeys spider monkeys, prehensile tail
Old world monkeys (more "evolved") baboons, macaques (rhesus) color vision
(rhesus used in research - centers)
Animal activists give primate researchers a hard time

Figure 25-13
Figure 25-14
(baboons - very interesting social life)

Great apes -

Figure 18-3
Chimpanzee chromosomes like ours

Figure 25-17
Famously studied by Jane Goodall

present controversy used in AIDS research

Gorilla - very different in zoos,
Studied by Schaller
Dian Fossey studied them and was murdered by poachers in 1985
Gorillas in the mist was a movie about her

Orangutan, Gibbon


Figure 17-14
fossils not in good places
scavange, animals, native groups want buried
Famous hoax, Piltdown man, confused issue
Discoveries continue
Organization (diagram) changes
Excitement, for instance Ice-man
4 million yrs ago, before that "hominids"
Australopithecus afarensis Lucy 2.8 - 3.6 MYA
walked upright before brain grew
Australopithecus africanus (tool use) East Africa

Homo habilis

Figure 17-15
(crude chipped stones) (stone age)

Homo erectus (Java, Peking)
1.5 million yrs ago

Homo neanderthalensis
200,000 yrs ago
co-existed with Homo sapiens
did they compete? did they interbreed?

Homo sapiens

Figure 17-17
paint in caves

Figure 17-16

Figure 17-18
out of Africa

Figure (Chapter opener)
Case study little people big story
Homo floresciensis

Questions used in 2007 & 2008 relating to this outline

Which form of life came into existence first?
(a) flowering plants
(b) reptiles
(c) invertebrates
*(d) prokaryotes
(e) eukaryotes

When Pangaea was formed
(a) the Cambrian explosion blew up the dinosaurs.
(b) coal was deposited.
(c) so were the first cells.
*(d) coastal habitats were lost.
(e) RNA replaced DNA as the hereditary molecule.

Dinosaurs are thought to have gone extinct
(a) in the Quaternary period during the ice ages that wiped out the mammoth.
(b) when ozone was depleted.
*(c) at the Cretaceous-Tertiary boundary when an asteroid or comet crashed into Earth.
(d) because they got buried in frequently flooded swamp forests in the Carboniferous period.
(e) when oxygen started to appear in the atmosphere.

About how long ago did the first cells appear?
*(a) 3.5 billion years
(b) 1.5 billion years ago when eukaryotes came into existence
(c) 3.5 million years
(d) not until there was sexual reproduction
(e) after photosynthesis evolved

There is a consensus that humans originated
(a) because of a mutation in their closest relatives, the New World monkeys.
(b) in Indonesia.
(c) while dinosaurs were still dominant.
(d) in Peking.
*(e) in Africa.

(a) were the earliest humans.
(b) are the recently-discovered small people nicknamed "Hobbits."
*(c) co-existed with Homo sapiens.
(d) were in the species Australopithecus, and Lucy is a famous fossil.
(e) are the missing link between prosimians and modern humans.

The geological time scale corresponds to sequences of rock formations and fossils that have been grouped into four broad eras (ordered from long ago to now)
(a) Precambrian, Mesozoic, Cenozoic, Pleistocene.
(b) Cenozoic, Mesozoic, Precambrian, Paleozoic
(c) Precambrian, Paleozoic, Cenozoic, Pleistocene.
(d) Paleozoic, Precambrian, Mesozoic, Cenozoic.
*(e) Precambrian, Paleozoic, Mesozoic, Cenozoic.

Most scientists attribute the mass extinction of the dinosaurs to
A) loss of habitat.
B) hunting by primitive humans.
C) plate tectonics.
D) predation by mammals.
*E) a meteor impact.

The endosymbiotic hypothesis accounts for the origin of which cell structure?
*A) chloroplast
B) cell wall
C) chromosome
D) plasma membrane
E) ribosome

The first cells were
A) deposited and are now the coal of today.
*B) from 3.5 billion years ago.
C) photosynthetic, somewhat like cyanobacteria of today.
D) terrestrial (land-dwelling).
E) eukaryotes.

The worst mass extinction event of all time
A) occurred when the mammoths went extinct.
B) happened because of the Cambrian explosion.
C) accompanied the 4 ice ages that drove the dinosaurs extinct.
D) was 4 billion years ago.
*E) was at the end of the Permian period.

Humans first appeared in the
A) Mesozoic era.
B) Carboniferous period.
C) Jurassic period.
*D) Quaternary period.
E) Precambrian era.

In addition to Homo, another genus of hominids was
A) the chimpanzee.
B) the Lemur.
C) the Neanderthal.
D) the Piltdown man.
*E) Australopithecus.

Hominids originated in
*A) Africa.
B) Peking.
C) Indonesia.
D) North America.
E) Australia.

Geologists can determine the age of a rock by measuring ________ in the rock.
A) ions
B) chitin
*C) the proportion of potassium-40 to argon-40
D) Euglena
E) coal

Hobbit-sized hominid fossils recently discovered on a remote oceanic island belonged to
A) the genus Australopithicus afarensis.
B) the same species as the cave man in the stone age.
C) the same species as us.
*D) the species Homo floresiensis.
E) the genus Homo neanderthalensis.

Questions used in 2002 relating to this outline (and other outlines)

Which gas was probably not abundant (during chemical and early biological evolution) until after the origin of photosynthesis?
*(a) ozone
(b) carbon dioxide
(c) methane
(d) nitrogen
(e) water vapor

"Pangaea" is a term applied to
(a) present day drift of land masses.
(b) a period in the Paleozoic era.
*(c) a supercontinent in the Paleozoic era.
(d) a domain in the 3-domain system.
(e) the shape of a bacterial cell.

(a) was released when the Cambrian exploded.
(b) served as the energy source of ancient bacteria.
(c) causes programmed cell death.
(d) arrived on Earth from the asteroid that arrived at the end of the Cretaceous.
*(e) is used to date fossils.

Which form of life came into existence first?
(a) flowering plants
*(b) prokaryotes
(c) invertebrates
(d) eukaryotes
(e) reptiles

The first biological organisms
(a) were probably eukaryotes.
(b) were probably autotrophs.
*(c) were probably heterotrophs.
(d) probably used DNA as their hereditary molecule.
(e) were probably photosynthetic.

Chemical evolution before the origin of life on Earth is believed to have taken place
(a) about 4000 years before Christ.
(b) about 10,000 years ago.
(c) about 1,000,000 years ago.
(d) about 1,000,000,000 years ago.
*(e) before any of the above.

Coal was formed
(a) from organisms killed during the Permean extinction.
(b) from flowering plants in a reducing atmosphere.
*(c) from primitive vascular plants in the Carboniferous period.
(d) from mats of Precambrian photosynthetic prokaryotes.
(e) from deposits of foraminiferans.

The dinosaurs disappeared abruptly before the close of the Cretaceous because
*(a) there was a profound shift in climate probably caused by collision with an asteroid.
(b) of the most recent ice age.
(c) there were sudden, massive upheavals in Earth's crust.
(d) of a pathogenic bacterium specific to dinosaurs.
(e) of the Hardy-Weinberg theorem.

The geological time scale corresponds to sequences of rock formations and fossils that have been grouped into four broad eras (ordered from long ago to now)
(a) Precambrian, Mesozoic, Cenozoic, Pleistocene.
(b) Cenozoic, Mesozoic, Precambrian, Paleozoic
(c) Precambrian, Paleozoic, Cenozoic, Pleistocene.
(d) Paleozoic, Precambrian, Mesozoic, Cenozoic.
*(e) Precambrian, Paleozoic, Mesozoic, Cenozoic.

Which would have come first?
(a) sexual reproduction
*(b) heterotrophic prokaryotes
(c) incorporation of bacteria (that eventually became mitochondria) into eukaryotes
(d) incorporation of photosynthetic bacteria (that eventually became chloroplasts) into the precursors of plant cells
(e) the invasion of land

Organisms that do not use oxygen in the process of respiration are
(a) heterotrophic.
(b) haploid.
*(c) anaerobic.
(d) symbiotic.
(e) eukaryotic.

Why do scientists think RNA was the hereditary molecule in the earliest organisms?
(a) RNA is more stable than DNA.
(b) RNA has fewer nucleotides and thus it is simpler.
*(c) RNA has properties like enzymes (usually proteins).
(d) The earliest organisms were viruses, and these contain only RNA.
(e) It was not until later that proteins evolved to take over hereditary function.

At the end of the Paleozoic, continents merged to Pangaea, and the loss of costal habitats contributed to which extinction?
(a) Precambrian
(b) Ordovician
(c) Devonian
*(d) Permean
(e) Cretaceous

Which is thought to have happened most recently?
(a) the first protobionts.
(b) the first heterotrophic prokaryotes
(c) oxygen production by photosynthesis.
(d) incorporation of bacteria that eventually became mitochondria into eukaryotic cells.
*(e) incorporation of bacteria that would eventually become chloroplasts into plant cells.

Fossil fuels
(a) are composed of carbon dioxide precipitated out in rock by chemical action.
*(b) are the remains of plants and animals of hundreds of millions of years ago.
(c) are the only form of carbon stored long-term by biological organisms long ago.
(d) deplete the ozone layer when burned.
(e) have caused an increase in atmospheric nitrogen when burned.

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