Age of the Universe

1
Age of the Universe

• The early universe was very hot and dark.
• Fiat Lux!
• There were no planets like the earth when the
  universe was young.

2
Helium to Carbon

• One Carbon atom is formed from the fusion of two
  Helium atoms.
• Heavier elements are formed from the fusion of
  Carbon.

3
Nucleosynthesis

• Stars burn with fusion reactions in their cores
• Fusion reactions produce heavier atoms from
  lighter atoms

4
All of the atoms in our bodies heavier than
lithium were made by the stars, then spread
through the Universe with the explosions of super
novae.
5
We are all star stuff.
6
The Great Bombardment

• The early solar system was full of colliding
  planets and planetoids
• The last important collision with the Earth was
  around 4 billion years ago

7
Chemical Evolution

• Earths early atmosphere contained water vapor,
  H2, CH4, NH3. (CHON)
• Primordial Soup
• This process requires nothing beyond normal
  chemistry

8
Evolution of Earths Atmosphere

• Anaerobic biosphere
• Harsh Environment
• Oxygen is toxic

9
Stromatolites

• Blue-green algae evolves
• Photosynthesis
• Sunlight CO2 H20 ? O2 C6H12O6

10
Black Smokers

• Super heated water coming from deep ocean vents.
• High concentrations of dissolved minerals.
• Offers a protected area that may have served as a
  haven for early life.

11
Life in extreme environments

• Exobiologists use life on earth found in extreme
  environments as models to study life that may be
  found in similar environments in space.

12
Mars

• Mars has long been a subject of speculation and
  investigation.
• Mars probably once had a warmer, damper
  environment.
• Evidence for surface water in the recent past.

13
ALH84001 and Viking

• Martian rocks contain what appear to be fossils
  of simple organisms
• New evidence from Viking data reanalysis
  discovers circadian rhythms in Martian soil
  samples

14
Europa

• Europa is a world frozen across its surface
• There is strong evidence that under the ice is
  the largest liquid ocean in the Solar System

15
Titan from 340,000 km

• Methane atmosphere 1.4 times that of Earth
• Oceans of hydrocarbons
• May look a lot like the primordial Earth

16
Lifes Story in a Nutshell

• After the first cell divided competition began.
• Given the low levels of competition, early life
  probably spread across the world in as little as
  a few years.
• Early cells would have found themselves spreading
  to new environments thus encouraging adaptation.
• Time and selection have produced complicated
  ecosystems.

17
Geologic Time

• The earth is old enough for the continents to
  have had enough time to reshape their
  configuration.

• Number millions of years ago

18
Mass Extinctions

• Cretaceous (About 65 million years ago.)
• Triassic (About 208 million years ago.)
• Permian (About 245 million years ago)
• Devonian (About 360 million years ago.)
• Ordovician (About 438 million years ago.)

19
Impact

• The Cretaceous Extinction is thought to have been
  brought about by an asteroid collision

20
Impacts Close Calls

• Size matters.
• Resilience of biosphere?

21
Energy Evolution
22
Open Closed Systems Chaos, Entropy and the
Drive to Complexity

• that energy can neither be created nor destroyed.
• that entropy always increases.

23
The Sun is the Earths external energy source.
24
Photosynthesis and Weather
Photons from the sun provide energy for plants.
Solar power drives large weather systems over the
Earths surface.
25
Earths internal energy source.
26
Characteristics of Life

• Ordered
• Metabolizes energy
• Reproduces
• Evolves
• Maintains homeostasis
• Responds to environment
• WHAT ABOUT VIRUSES?

27
Evolution
28
The Fossil Record

• How fossils form
• Transitions
• Estimates state that only one species in 10,000
  is represented in the fossil record.

29
Key ideas about the fossil record

• The older the rocks the greater are the
  differences with modern life forms
• Overall trends in complexity
• Most species that have existed on the Earth are
  already extinct

30
Biochemical Evidence

• Our DNA shares more in common with closely
  related organisms
• We share 98.4 of our DNA with chimps, 86 with
  rattlesnakes and 58 with yeast

31
Vestigial Organs and Imperfect Design

• Some animals possess organs with little or no
  purpose. Such organs are called vestigial organs.

32
Vestigial Organs

• Appendix
• Your tailbone
• Muscles you use to wiggle your ears
• Flightless insects often have tiny wings
• Certain snakes have leg bones

33

• "Oh my dear, let us hope that what Mr.Darwin says
  is not true. But if it is true, let us hope that
  it will not become generally known!" 

34
Early Ideas

Darwins mapping expedition on H.M.S. Beagle
1831-1836
35
(No Transcript)
36
(No Transcript)
37
Darwins Conflict

• Charles Darwin Alfred Wallace

38
Darwin Publishes 1869

• Storm of controversy
• Uses and misuses of his ideas
• Immediate Best Seller!
• Read Darwins books on line here
  http//www.literature.org/authors/darwin-charles/

39
Natural Selection

• Every population contains genetic diversity.
• Many more individuals are born than can survive.

40
Adaptation

• Competition among individuals within a species
  over generations in response to a changing
  environment

Occurs during the slow course of evolution.
41
Rate of Evolution

• There are different ideas about the rate of
  evolutionary change.
• We see both gradual changes and mass extinctions
  followed by adaptive radiations.
• What is it that evolves?

42
Time Line

• The number of families has increased through time
  even as species have gone extinct.
• Ecosystems becoming more complex

43
Five Kingdom Classification System
44
Kingdom Characteristics

• Animals multicelled, heterotrophs
• Plants multicelled, autotrophy
• Protists single multicelled autotrophs
  heterotrophs
• Monera single celled, prokaryotes
• Fungi multicelled, heterotrophs

45
Taxonomic Nomenclature

• Hierarchical classification system used for all
  species
• Universal, unambiguous communication
• 1,435,662 species identified so far

46
Group No. of described species Bacteria and
cyanobacteria 4,760 Fungi
46,983 Algae 26,900 Bryophytes (mosses
and liverworts) 17,000 Gymnosperms
(conifers) 750 Angiosperms
(flowering plants) 250,000 Protozoans
30,800 Sponges 5,000 Corals and
jellyfish 9,000 Roundworms and
earthworms 24,000 Crustaceans
38,000 Insects 751,000 Other arthropods
and minor invertebrates 132,461 Mollusks
50,000 Echinoderms 6,100 Fishes
19,056 Amphibians 4,184
Reptiles 6,300 Birds
9,198 Mammals 4,170 Total species
1,435,662
47
Three Domains

• Recent change to classification system
• Early evolutionary split between Eubacteria and
  Archaea
• Genetic diversity in Monera recently discovered
  through better molecular techniques

48
Human Evolution

• The evolution of humans is no different from the
  evolution of any other species

49
SEX
50
Credits

• Life in extreme environments, Mars, ALH0001,
  Europa NASA
• Titan http//antwrp.gsfc.nasa.gov/apod/ap041026.h
  tml
• Adaptation Encarta
• Darwin http//www.turnpike.net/mscott/darwin.htm
  
• Geologic time http//www.ucmp.berkeley.edu/exhibi
  t/geology.html
• Black Smokers http//walrus.wr.usgs.gov/pubinfo/s
  mokers.html
• Great Bombardment http//www.uky.edu/ArtsSciences
  /Geology/webdogs/time/hadean/hade1.htm
• Natural Selection http//www.sprl.umich.edu/GCL/p
  aper_to_html/selection.html
• Stromatolites Stromatolites of Hamlin Pool,
  Shark Bay, W. Australiahttp//www.virtualtravelle
  r.org/Australia13.htm
• Sun/earth http//science.nasa.gov/newhome/images
  /define_SUNEARTH.GIF
• Early atmosphere Joe Tucciarone
  http//www.novaspace.com/LTD/TUCC/PIX/Atmo.jpeg
• Continental drift animation http//www.ucmp.berk
  eley.edu/geology/anim4.html
• Photosynthesis animation http//www.bio.davidson.
  edu/courses/Bio111/Photosynth/PS.html
• Number of species http//www.bwf.org/bk/pamayanan
  /r-howmany.html
• Three Domains http//www.ucmp.berkeley.edu/alllif
  e/threedomains.gif