Hist 103 Final

node

decision points

contingency

the notion that future events are dependent on passed ones but not determined or predicted

Teleology

the belief that some process unfolds toward a predetermined goal, divinely ordained or just destined

Scale

how big/how small

Big Bang time

13.7 bya

big bang

small infinitely dense then rapidly expands, still expanding today

10^43 seconds

Planck time, universe is smaller than Planck length, nothing before this, gravity appears

10^-35

inflation begins, energy and matter are interchangeable, e = mc^2, gravity, strong nuclear force, quark soup

10^-6

temp fell to 1 trillion K, quarks stable enough to bond

1 second- 2 minutes

1 electron per proton, 1 billion K, nuclei formed

380,000 years after big bang

temp fell to around 3,000 K, threshold, end of radiation era, neutral atoms with electron orbits, gravity

Hubble constant

rate of universe expansion seen through red shift

cosmic background radiation

radiation left over from the big bang

makeup of universe after big bang

about 75% hydrogen, 25% helium, similar today

Lord Brahma

hindu origin story, creator of universe

contingency in big bang

tiny imbalance of matter and antimatter, slightly more matter, that's why we're here. Proof is CBR unevenly distributed.

200 million years after Big Bang

"Dark Age" universe cools and expands, matter clumps

at 200 million years after Big Bang

stars and galaxies begin to form. hydrogen and helium

Milky Way age

13 billion years

Msolar system distance from center of galaxy

26,000 light years

Nebular Hypothesis

swirling massive clouds of dust, gravity pulls into center, sun ignited and remaining stuff is planets

Earth special

wwater, tectonic activity, size, distance from sun, MOON

Theia

4.5 bya earth and companion planet collided, became molten, became earth and moon

moon benefits

slow down earth's spin, regulates tides, keeps axis stable

Hadeon Era

4.6-4.0 bya, after theia, lots of asteroids, crust began to harden, cooled to 3000 degrees, black sphere with cracks of lava, red sky, rained for millions of years to make oceans

both shape history

contingent and deterministic events

Anthropic Principle

we live on an Earth designed for life

Strong Anthropic Principle

The circumstances in our universe have made the emergence of life inevitable, perhaps because the universe way designed that way

Weak Anthropic Principle

The universe just happens to be this was, and if it were any different we wouldn't observe it

what is life

organized cellular structure, reproduces, store info (genetics), metabolism, composed of organic things

steps of life emergence

1. building blocks: amino acids, sugars, lipids form 2. come together to make macromolecules 3. molecular selection, symmetrical efficient bonds (RNA/DNA) 4. Replication

Complex adaptive systems

interact and adapt with their environments to survive, determinism and contingency

Life made of?

lipids, carbohydrates, proteins, nucleic acids

RNA world hypothesis

RNA formed first (genes first), primordial soup and acted like proteins and replicated

Iron-sulfide world hypothesis

metabolism came first

Panspermia

life originiated somewhere else and was delivered to Earth through meteors

3.5 bya

first life: prokaryotes

2.5 bya

Great Oxygenation Event, photosynthesis in cyanobacteria, contingent event

1.9 bya

first Eukaryotic cell, one prokaryote absorbed another, "Last Common Ancestor"

Dark matter

matter that does not give off electromagnetic radiation, 90% of universe

sun/solar system age

4.56 billion years old, will live for 4-5 billion more years

T Tauri Wind

100,000 years after sun's formation, blasted away remaining gas and dust in inner orbits and young earth atmosphere

evidence for early earth

seismograph, relative dating, radiometric dating, meteorites

Uniformitarianism

geologic processes happened over huge periods of time, deep time

Archean Era

3.8 bya, continental crust, seas, carbon dioxide atmosphere, Pangaea, age of bacteria

synestias

impact-generates hybrid between planet and disk

cladogram

shows the evolutionary relationships among a group of organisms, how long ago that had a common ancestor

natural selection

determines how evolution functions

struggle for existence

scarcity of food, competition among species

allopatric speciation

populations get separated and eventually grow into separate populations with different features and genetics, evolution happens quicker in small group

Bottleneck events

The Great Oxygenation Event, Snowball Earth

Snowball Earth

700 mya, during breakup of Rodenia, produced massive ice age

Ediacaran Era time

560-540mya

Ediacaran importance

first multicellular life

Path dependency

the idea that certain possibilities are made more or less likely because of the historical path taken

Path dependency examples

bilateral symmetry, varnanimalcula

540 mya

Cambrian explosion, marin life

50 mya

all animal groups that live now were there

Arthropods

segmentation, same body plan, trilobites

niche

particular way of living for an organism that seems to have been adapted or sculpted by evolutionary processes

taxonomy

biological classification

acquired traits

occur in a life time, a buff guy won't have a buff kid

Phanerozoic Eon

last 600 ma, all of Earth's history

Carboniferous Period

300 mya, highest oxygen concentration, dinosaurs came about

Random walk

a stochastic or random process describing a path consisting of random steps through some mathematical space (integers), memory of previous steps

Just because there is a trend...

does not mean its destined

Evolution trends

greater size, complexity because it was the only way to go

stochastic

random, unpredictable

Big 5 extinctions

End-ordovician, devonian, permian, triassic, cretaceous

Importance of extinctions

Leads to new opportunities for the survivors, new niches, rapid genetic evolution, bottleneck effects

extinctions causes

climate change, change in sea level, plate tectonics

1st extinction

end ordovician, 425 mya, led to colonization of land, planets first, first land animal (arthropods)

2nd extinction

end Devonian, synapses diversified, pelycosaurs, therapsids (mammal-like reptiles)

3rd extinction

permian, only synapses to survive were mammals, biggest, caused by global warming and volcanoes, no more large vertebrates

Triassic

After permian, new body plans, dinosaurs rose, bipedalism, Cambrian explosion like

4th extinction

50 mya, maybe asteroid, higher CO2, killed off Dinosaur competitiors

Jurassic

age of dinosaurs, mammals are small foragers, flight evolved

5th extinction

65 million years ago, huge asteroid impact, changed earth completely, ended Dinos, sunlight blocked for year

Catastrophism

geological changes have taken shape through sudden and dramatic catastrophes, such as major volcanic events, floods, and earthquakes. Explains why the fossil record has sudden extinctions.

punctuated equilibrium

Pattern of evolution in which long stable periods are interrupted by brief periods of more rapid change

large scales vs. small

large: more stochastic, small: more deterministic

true symbiosis

one or both partners can no longer survive without the other

mammals first appeared

triassic

Gaia

Living organisms constitutes a single earth-wide system, Huge self regulating superorganism, keeping earth's conditions good for life

patter of species

migration, innovation, growth, overexploitation, decline, stabilization

Kt Boundary

Time of mass extinction of dinosaurs

Lucy

bipedal hominine, 3.2 mya, 40% fossil

mammal

milk, three middle ear bones, neocortex in the brain

Morganucodon

First true mammal, protected brain, strong jaw, faster digestion and metabolism, replacing teeth, more upright posture, flexible

Therian mammal

primates, placentals, marsupials

KT event name

K/Pg event

Micocene

23 mya, diversification of carnivores, temp drop

last common ancestor of humans and chimps date

6-7 mya

amount of DNA shared with chimps

98.4%

contingent event in human and chimps

human ancestor had mutation where two chromosomes fused

East African Rift Valley

birthplace of humanity, 6-4.5 mya

advantages of bipedalism

Free hands, heat regulation, efficient over distance, see further

Australopithecus anamensis

4.2 - 3.8 mya The oldest species of australopithecine from East Africa and a likely ancestor to A. afarensis.

Australopithecines

walked upright, primitive stone tools, ate meat without first, omnivore, bipedal

what separates human

internal life, recognize thoughts and feelings of others, others have internal life