The History of Life on Earth

1
The History of Life on Earth
2
LIFE
3
Formation of the Earth

• Earth was formed approx. 4.54 billion years ago
  out of the solar nebula.
• Initially molten, the outer layer cooled to form
  a crust about 4.3 B.Y.A. as water was brought to
  Earth by meteors.

• By 3.9 B.Y.A. Earth had cooled enough to form
  oceans.

4
Formation of the Earth

• Out gassing and volcanic activity produced the
  primordial atmosphere consisting of water vapor,
  carbon dioxide, hydrogen, ammonia, methane, and
  other gasses.

• The primordial ocean was most likely made up
  of water, with methane,
• ammonia, hydrogen, sulfur, and carbon dioxide.

• No free oxygen in the
• atmosphere or oceans at
• this time.

5
First Life on Earth- Biogenesis

• Life metabolism and reproduction, growth and
  response to stimuli (adaptation).
• Proto cells cell-like spheroid formed from
  proteinoids (chained groups of amino acids).
• Proto-cells containing RNA may have been the
  first cellular life forms on Earth. (3.8 B.Y.A.)

6
The First Cells

• Prokaryotic cells (bacteria) Cells without a
  membrane-bound nucleus. (3.5 - 2.5 B.Y.A.)
• Archaebacteria- first autotrophs, blue-green
  algae (supplied the first oxygen to the
  atmosphere)
• Genetic material is in a circular loop called a
  plasmid

7
The First Cells

• Eukaryotic cells cells with a membrane-enclosed
  nucleus.
• Developed approx. 2 billion years ago
• Include all complex cells and make up all
  multi-cellular organisms.
• Animals, plants, fungi, and protists are
  eukaryotes.

8
The Precambrian

• Proterozoic Eon 2500 to 543 mya
• Paleoproterozoic Era 2500 to 1600 mya
• Stable continents
• 2400 2100 Huronian ice age
• Mesoproterozoic Era 1600 to 900 mya
• Formation of supercontinent Rodinia
• Eukaryotic cells appear
• 1200 mya spore/gamete formation (sexual
  reproduction)
• Photosynthetic organisms proliferate, oxygen
  above 10
• Formation of the ozone layer
• 950 mya start of Stuartian-Varangian ice age

9
The Precambrian

• Proterozoic Eon 2500 to 543 mya
• Neoproterozoic Era 900 to 643 mya
• Earth day is 18 hours long
• Formation of a supercontinent
• Cryogenian Period 850 to 635 mya
• 750 mya End of last magnetic reversal
• 650 mya mass extinction 1 of 70 of dominant
  sea plants.

10
Bellringer Wed, 02/18

• What is a mass extinction? (Educated guess of
  look it up!)
• Name 3 things that happened during the
  Precambrian Era/Eon!
• Reminders HW 4 due Fri, LAB FEE anytime, Quiz
  Fri Grade Progress Reports go out next
  week!

4 Minutes
1 Minute
Times Up!
5
2
1
3 Minutes
30 Seconds
2 Minutes
10
9
8
7
6
4
3
11
TIME EON ERA PERIOD EPOCH
12
Phanerozoic Eon (543 mya to present)

• Paleozoic Era 543 to 251 mya
• Vendian (Ediacaran) Period 635 to 543 mya
• 570 mya end of Stuartian-Varangian ice age
• Soft-bodied organisms developed (first jellyfish)
• Cambrian Period 543 to 490 mya
• Most of the major groups of animals first appear
• 530 mya Animals with shells appeared

13
Phanerozoic Eon (543 mya to present)

• Paleozoic Era 543 to 251 mya
• Ordovician Period 490 to 443 mya
• Diverse marine invertebrates, first vertebrates
  appear, first green plants and fungi on land
• 450 mya start of Andean-Saharan ice age
• 443 mya mass extinction 2 of many marine
  invertebrates.
• Silurian Period 433 to 417 mya
• End of Adean-Saharan ice age, stabilization of
  Earths climate
• Coral reefs appeared, first fish with jaws,
  spiders, centipedes and plants appear on land.

14
Phanerozoic Eon (543 mya to present)

• Paleozoic Era 543 to 251 mya
• Devonian Period 417 to 354 mya
• Ferns and seed-bearing plants appeared, first
  amphibians
• Wingless insects and vertebrates appear on land
• Pannotia fragmented into Laurasia and Gondwana
• Atmospheric oxygen level about 16
• 374 mya mass extinction 3 of 70 of marine
  species

15
Phanerozoic Eon (543 mya to present)

• Paleozoic Era 543 to 251 mya
• Carboniferous Period 354 to 299 mya
• Mississippian Epoch 354 to 318 mya
• Karoo ice age, large primitive trees, vertebrates
  appear on land, first winged insects
• Pennsylvanian Epoch 318 to 299 mya
• First reptiles, atmospheric oxygen over 30,
  giant arthropods, deposits of coal form in Europe
  and Asia.

16
Phanerozoic Eon (543 mya to present)

• Paleozoic Era 543 to 251 mya
• Permian Period 299 to 251 mya
• Formation of the supercontinent Pangaea, Earth is
  cold and dry
• Conifers (pine trees) appear
• 260 mya end of Karoo ice age
• Oxygen levels drop from 30 to 12
• 251 mya Great Permian-Triassic mass extinction
  4 90 of ocean dwellers and 70 of land plants
  and animals.

17
PANGEA
18
Phanerozoic Eon (543 mya to present)

• Mesozoic Era 251 to 65 mya
• Triassic Period 251 to 200 mya
• Breakup of Pangea starts
• First dinosaurs appear, first evidence of mammals
• 201 mya mass extinction 5 20 of marine
  animals

19
Phanerozoic Eon (543 mya to present)

• Mesozoic Era 251 to 65 mya
• Jurassic Period 200 to 145 mya
• Earth is warm no polar ice
• Age of the dinosaurs giant herbivores and
  vicious carnivores.
• North America splits from Europe.
• 150 mya First birds (archaeopteryx) appear

20
Phanerozoic Eon (543 mya to present)

• Mesozoic Era 251 to 65 mya
• Cretaceous Period 145 to 65 mya
• Africa and India split from Antarctica, South
  America splits from Africa
• Flowering plants, crocodiles appear, modern
  mammals and birds developed.
• 70 mya T-Rex thrived
• 65 mya Meteor impact, Yucatan, Mexico mass
  extinction 6 of dinosaurs.

21
(No Transcript)
22
Phanerozoic Eon (543 mya to present)

• Cenozoic Era 65 mya to today
• Tertiary period 65to 1.8 mya
• Paleocene Epoch 65 to 54.8 mya
• Appearance of placental animals
• Formation of Rocky Mtns, major global warming

• Eocene Epoch
• 54.8 to 33.7 mya
• India and Asia collide forming the Himalayas,
  Australia separates from Antarctica.
• Small modern mammals appear.

23
Phanerozoic Eon (543 mya to present)

• Cenozoic Era 65 mya to today
• Tertiary period 65 to 1.8 mya
• Oligocene Epoch 33.7 to 23.8 mya
• Start of Pleistocene ice age
• Appearance of grasses, elephants, camels, early
  horses.
• Miocene Epoch 23.8 to 5.3 mya
• The plants and animals of the Miocene were fairly
  modern.
• Mammals and birds were well-established. Whales,
  seals, and kelp spread.

24
Phanerozoic Eon (543 mya to present)

• Cenozoic Era 65 mya to today
• Tertiary period 65to 1.8 mya
• Pliocene Epoch 5.3 to 1.8 mya
• Accumulation of ice at the poles
• Spread of grasslands, rise of long-legged grazing
  animals
• 2.4 mya Homo habilis appears- tool making
  humanoids

25
Phanerozoic Eon (543 mya to present)

• Cenozoic Era 65 mya to today
• Quaternary Period 1.8 mya to today
• Pleistocene Epoch 1.8 mya to 10,000 yrs ago
• Homo erectus moves out of Africa
• Presence of large land mammals and birds
• Global cooling and glaciation
• Neanderthals 500,000 yrs ago
• Homo sapiens 200,000 yrs ago

26
Phanerozoic Eon (543 mya to present)

• Cenozoic Era 65 mya to today
• Quaternary Period
• 1.8 mya to today
• Holocene Epoch 11,600ya to today
• Development of agriculture and domestication of
  animals starts
• 9,000 ya metal smelting found
• 5,500 ya wheel invented
• 5,000 ya first writing
• 4,500 ya Pyramids in Egypt
• 2,000 ya Christian Era starts
• 250 ya industrialization Age
• 50 ya First Space Travel