recording natural history. break-down of time different periods of earth’s history are broken into...

Recording natural history

Break-down of time

• Different periods of Earth’s history are broken into periods of time,just like a year is broken into months, weeks, days and hours

• Earth’s history is broken into eons, eras, periods, and epochs

Eons – Billions of years • Haden: Earth before life evolved

3.5 to 3.9 Billion years ago • Achaean: Earth with only prokaryotic cells

– 3.9 to 2.5 Billion years ago

• Proterozoic: Current Eon– 2.5 BYA to present

How time periods are distinguished

• Major geological events: The movement of tectonic plates to form continents and super-continents

• Changes in climate: a change from an ice ace to a warming period

• Mass extinctions or explosions: Changes in the types of life forms on earth

Haden Eon 4.5-3.9 BYA

• The first 13% of the Earth’s history

• Earth is a solid lifeless planet

• No liquid water, little O2 in the atmosphere

• Relative to a calendar year: Jan 1st – Feb. 25th

Achaean Eon 3.9-2.5 BYA

• Earth has a crust & ocean• Life forms in the sea• Prokaryotes including photosynthetic blue-green

algae & later bacteria• Feb. 25th - April 17th

Proterozoic Eon: Precambrian Era2.5 BYA – 540MYA

• Super continent Rodinia

• 21% O2 in Atmosphere

• First Eukaryotic cells & sexual reproduction– July 13th

• First Multicellular organism (seaweed/algae)– Aug 31st

Haden

lifeless Earth

Achaean Achaean

Prokaryotic lifeProkaryotic life

Little OLittle O22

Proterozoic

Eukaryotic life, multicellular plants, First plants & soft bodied animals in oceans later vascular

plants fish, arthropods in ocean

Insects, amphibians & reptiles on land

Review of Earth’s first 3.9 Billion years

Paleozoic Era From the Cambrian explosion to the

Permian extinction

Cambrian Explosion 540-490 MYA

• 2 continents: mild climate• All life in ocean only• Sponges & coral • Then mollusks (clams)• Later arthropods (trilobites) • Finally chordates – pre-vertebrate ancestors• Nov. 17 - Nov. 21st

Paleozoic Era

Ordovician Period 490-443 MYA• More Continents • First vertebrates – armored fish• First plants & invertebrates on land• Nov. 21st – Nov. 24th

Paleozoic Era

Silurian Period 443-417 MYA • Most continents are near equator

First: nautilus, jawed fish, shark, lungfish

Lots of arthropods

more complex plants on land (vascular)

Nov 24th – Nov. 27th

Paleozoic Era

Devonian Period 417-354• Europe & N. America at equator & S America &

Africa over S. pole• Warm & moist• First: air breathing Arthropods • First: insects (beetles), amphibians, seed plants (ferns) • Nov. 27th - Dec 1st

Paleozoic Era

Carboniferous Period 354-290 MYA

• First swampy & warm then cold glaciers • Oceans: armored fish extinct • greater diversity of fish etc.• Land: Giant insects, first reptiles• Dec 1nd – Dec 6th

Paleozoic Era

Permian Period: 290-248• Supercontinent Pangaea – all climate zones

• Glaciers & deserts

• Mass extinction 99% of all life gone

• Modern insects, fewer amphibians, many reptiles

• Dec. 6th - Dec 10th

Paleozoic Era

Mesozoic Era The rise and fall of dinosaurs

Triassic Period 248-206 MYA• Pangea covers ¼ Earth’s surface• Warm and dry climate• On land: 1st small dinosaurs • Plants: Ferns, ginkgoes, & conifers • In ocean: 1st reptiles • Dec. 10- Dec. 14

Mesozoic Era

Jurassic Period 206-144 MYA

• Pangaea begins to break apart• Dinosaurs dominate land and sea• First bird• Early amphibians go extinct, replaced by frogs & salamanders • First mammals (small shrew like) • Dec. 14th - Dec. 19th

Mesozoic Era

Cretaceous Period 144-65 MYA• Sea levels rise: no ice at poles• Large dinosaurs dominate • most modern insects• First flowering plants• Ends with mass extinction of Dinosaurs

Dec. 19th – Dec 25th

Mesozoic Era

Cenozoic Era

Paleocene Epoch 65-55 MYA

• Mammals diversify: first only marsupials • Inland seas dry up, Australia breaks free• Later placental mammals • First dogs & cats• Dec 25th

Oligocene Epoch 34-24 MYA • Lots a tectonic plate movement temperate

climate

• Grass land expand forest decline

• First primate

• Dec. 28

Cenozoic Era

Miocene Epoch 24-5 MYA

• Climate cools

• Half of modern mammals exist

• Many modern bird groups

• First: apes

• Dec 29th – Dec. 31st 3PM

Pliocene Epoch 5-1.8 MYA

• Alps rise & Central America formed

• Camels, horses, & giant ground sloths in N. America

• Australopithecines – 1st human ancestor

• Dec 31st 3:00 PM – 10 PM

Cenozoic Era

Pleistocene Epoch 1.8 M- 10,000• Great ice age – 30% earth covered

in ice

• Wooly mammoths & saber-tooth cats go extinct

• Homo Habilis: tool maker

• Dec. 31st: 10PM – 11:48 PM

Holocene Epoch 10 TYA - today• Glaciers retreat, sea levels rise, deserts form

• 1st humans modern civilizations

• The world as we know it

Review of last 240 Million years

First Dinosaurs

Last Dinosaurs

Flowering Plants

First Mammals

First bird

First monkeyFirst human

Review1. What was the surface of the earth life for most of the

Haden Era? 2. During which era did multicellular life evolve?3. Which is a shorter period of time and eon or an era? 4. During which period did flowering plants evolve?5. When did the first birds evolve?6. What were the first vertebrates?7. When did the first air breathing arthropods evolve. 8. What was the name of the supercontenent formed

during the Permian?