M3: History of Life on Earth Flashcards
The longest time unit in the GTS
eons
the 4 eons?
hadean
archean
proterozoic
phanerozoic
hadean eon is also called as
unseen
archean eon is also called as
ancient/primitive
proterozoic eon is also called as
before complex life
phanerozoic eon is also called as
visible life
The term was coined in 1972 by geologist Preston Cloud.
hadeon eon
is derived from Hades, Greek for underworld, referring to the hellish conditions on the planet at the time.
hadean
hadean eon was later classified as the ________ period by W. Brian Harland.
Priscoan
the time/period of hadean eon
4.6 to 4 billion years
what is the atmosphere of hadean eon?
Hot, thick, steamy, and full of ______ and _____.
Made up of mostly _________ _______ and water vapor, with traces of ________ and smelly ______ compounds.
Hot, thick, steamy, and full of dust and crud.
Made up of mostly carbon dioxide and water vapor, with traces of nitrogen and smelly sulfur compounds.
Geology of hadean eon
Covered with oceans of liquid _______ , boiling ________ , and impact _______.
Covered with oceans of liquid rock, boiling sulfur, and impact craters.
Life Forms of hadean eon
Small amounts of organic ________ has been found that probably may be an evidence of first life on earth.
Small amounts of organic carbon has been found that probably may be an evidence of first life on earth.
Ended with the cooling of the earth’s temperature.
hadean eon
The name _______ is derived from the ancient Greek (Arkhe), meaning beginning or origin.
archean
It was first used in 1872, Which means “the earliest geological age”
Archean Eon
time/period of archean eon
4 to 2.5 billion years ago
atmosphere of archean eoN??
Comprised ______ , _________, and other gases.
Most of the carbon dioxide have been chemically changed into _________ and deposited at the bottom of the ocean.
Comprised methane, ammonia, and other gases.
Most of the carbon dioxide have been chemically changed into limestone and deposited at the bottom of the ocean.
geology of archean eon?
Formation of the __________ ________ rock.
Small “island” land masses floated in the ________ “seas.”
Start of the formation of _________
Water from _______ and hydrated minerals condensed in the atmosphere and fell as ________ rain, cooling the planet and filling the first oceans with liquid _____.
Formation of the continental shield rock.
Small “island” land masses floated in the molten “seas.”
Start of the formation of oceans
Water from comets and hydrated minerals condensed in the atmosphere and fell as torrential rain, cooling the planet and filling the first oceans with liquid water.
life forms of archean eon
_________ _________ such as photosynthetic bacteria, (Cyanobacteria) Stromatolites, Single-celled archaea extremophiles
Microscopic prokaryotes such as photosynthetic bacteria, (Cyanobacteria) Stromatolites, Single-celled archaea extremophiles
ARCHEAN EON
Life began in the oceans about ____ billion to ____ billion years ago.
Life began in the oceans about 3.5 billion to 2.8 billion years ago.
The oldest fossils ever found (3.5 bya)
Stromatolites
Are layered bio-chemical accretionary structures that formed in shallow water by the trapping, binding, and cementation of sedimentary grains of microorganisms.
Stromatolites
The name ____________ comes from Greek and means “earlier life”.
proterozoic
time/period of proterozoic eon
2.5 GA to 541 MA
atmosphere of proterozoic eon
Mostly ______ , with a little water vapor and carbon dioxide.
With Free ______ released by ____________
Mostly nitrogen, with a little water vapor and carbon dioxide.
With Free oxygen released by cyanobacteria
geology of proterozoic eon
Formation of supercontinents: _________
Frequent movement of earth surface ( Plate Tectonics) and _________ _______.
Formation of supercontinents: Rodinia
Frequent movement of earth surface ( Plate Tectonics) and continental collisions.
proterozoic eons
1.7 GA - Appearance of single celled __________ .
511 MA - appearance of ______________organism.
Life is still found only in the _______.
1.7 GA - Appearance of single celled eukaryotes.
511 MA - appearance of multicellular organism.
Life is still found only in the ocean.
PROTEROZOIC EON
Extinction of many anaerobic bacteria
GREAT OXYGENATION EVENT
Approximately 635 million to 541 million years ago
Autotrophs and soft-bodied heterotrophs
The Ediacaran Period
The Ediacaran Period
Fossils:
Ediacaran biota
- ________
- ___________
Charnia
Dickinsonia
Lasted for 36 million years
Snowball Earth
Caused by a 250 million year lull in volcanic activity.
a
Snowball Earth
This caused a decrease in the carbon dioxide of the atmosphere resulting in a climate cool down
Snowball Earth
The term “phanerozoic” was first introduced by the American geologist ________ ________ ________(1876–1953).
The term “phanerozoic” was first introduced by the American geologist George Halcott Chadwick (1876–1953).
The term phanerozoic is derived from the Ancient word “phanerós” meaning ________ and “zōḗ” meaning _______.
The term phanerozoic is derived from the Ancient word “phanerós” meaning visible and “zōḗ” meaning life.
Because it was once believed that the life began in ___________ , the first period of the phanerozoic eon.
Because it was once believed that the life began in Cambrian, the first period of the phanerozoic eon.
time period of phanerozoic eon
541 MA to present
s the eon of abundant complex life.
Phanerozoic Eon
It is the eon we are living in.
Phanerozoic Eon
Phanerozoic eon
It is divided into 3 Era
P__________ Era
M___________ Era
C___________Era
It is divided into 3 Era
Paleozoic Era
Mesozoic Era
Cenozoic Era
The term ‘Paleozoic’ has been derived from Greek words: palaios meaning ‘__________ ‘ and zoe meaning ‘life’
The term ‘Paleozoic’ has been derived from Greek words: palaios meaning ‘ancient’ and zoe meaning ‘life’
Marks the beginning of life on our planet.
Paleozoic Era
It was the period of early life where plants, corals, mollusks, insects, fish, and many other living organisms emerged.
Paleozoic Era
period of paleozoic era
- p_________
- carboniferous - P____________ and m____________
- d_______
- si_________
- o________
- ca_________
- permian
- carboniferous - pennsylivanian and mississippian
- devonian
- silurian
- ordovican
- cambrian
time or period of paleozoic era
542 -252 MA
atmosphere of paleozoic era
___________, oxygen, ________ _________ and other trace gases
Nitrogen, oxygen, carbon Dioxide and other trace gases
geology of paleozoic era
Formation of _________chains, formation of ___ beds.
formation of ____________
Earth’s surface experienced a lot of activity, including shifting of ___________ plates,
Formation of mountain chains, formation of coal beds.
formation of continents
Earth’s surface experienced a lot of activity, including shifting of tectonic plates,
At the beginning, a supercontinent called ____________ broke up into smaller continents.
At the beginning, a supercontinent called Pannotia broke up into smaller continents.
At the end of Permian, all the landmasses merged again to form a supercontinent called _________.
At the end of Permian, all the landmasses merged again to form a supercontinent called Pangaea.
climate of paleozoic era
There are extreme shifts in climate in each era
Cambrian - t___________
Ordovician and Silurian periods - warm _____________ climate interrupted by the Andean-Saharan Ice Age.
Devonian and Carboniferous - _______ until the Karoo Ice Age at the end of Carboniferous
Permian period - _______ and _______ continental climate on the enormous Pangea continent.
climate of paleozoic era
There are extreme shifts in climate in each era
Cambrian - temperate
Ordovician and Silurian periods - warm greenhouse climate interrupted by the Andean-Saharan Ice Age.
Devonian and Carboniferous - stable until the Karoo Ice Age at the end of Carboniferous
Permian period - harsh and dry continental climate on the enormous Pangea continent.
life forms of paleozoic era
______________ (animals without backbones) such as corals, brachiopods, mollusks, and arthropods such as trilobites ruled the oceans in the early and middle parts of the Paleozoic.
.
_________ (including fish, amphibians, and reptiles) began to flourish in the later Paleozoic.
Invertebrates (animals without backbones) such as corals, brachiopods, mollusks, and arthropods such as trilobites ruled the oceans in the early and middle parts of the Paleozoic.
.
Vertebrates (including fish, amphibians, and reptiles) began to flourish in the later Paleozoic.
Animals and plants populated the land (but many still lived in the ocean!).
Paleozoic Era
60% of invertebrates in the oceans and seas became extinct.
May be triggered by volcanic eruptions
Late Ordovician Mass Extinction
Monsoons affected the subtropical east coast but that interior/ center of Pangaea was dry.
Appearance of Reptiles that can survive in dry land.
PALEOZOIC ERA
252 mya 70% of the land vertebrates and 96% of the marine species disappeared from the fossil record including all survivors of previous extinction like trilobite
Paleozoic Era
Mesozoic era 3 periods
c_________
j__________
t_________
Mesozoic era 3 periods
cretaceous
jurassic
triassic
time/period of mesozoic eon
253 to 66 million years ago
geology of mesozoic eon
separation of supercontinent pangaea
climate of mesozoic eon
The climate is _______ throughout the ______ and ______ period but towards the middle of the ________ period the climate became warmer.
Then global cooling occurred at the end of the _______________
The climate is warm throughout the triassic and jurassic period but towards the middle of the cretaceous period the climate became warmer.
Then global cooling occurred at the end of the Mesozoic
life form of mesozoic eon
Appearance of _________, birds, plants, and __________
Appearance of dinosaurs, birds, plants, and mammals
were reptiles, however there is some evidence that they may have been warm-blooded.
Dinosaurs
During the late Mesozoic, ______ evolved from a group of small carnivorous dinosaurs.
birds
Plants
_______ trees evolved at the beginning of the Mesozoic.
The first flowering _____ evolved towards the end of the Mesozoic.
Plants
Conifer trees evolved at the beginning of the Mesozoic.
The first flowering plants evolved towards the end of the Mesozoic.
evolved during the Mesozoic but there were relatively few species and they were small in size.
Mammals
uring the Mesozoic, _______ were eaten by carnivorous dinosaurs.
Mammals
At the end of the Mesozoic, the Cretaceous-Tertiary Mass Extinction occurred.
This was the extinction event that killed the dinosaurs (among others).
The K-Pg Event
Many of the animals and plants that survived the extinction event (such as mammals and birds) went on to become very abundant afterward.
The K-Pg Event
periods of cenozoic era
- q_________
- n_______________
- p___________
quaternary
neogene
peloegene
time/period of cenozoic era
67 million years ago to present
geology of cenozoic era
The _________Ocean continues to widen as new ocean crust is formed at the Mid Atlantic Ridge.
India collided with the Asian continent forming the ___________ Mountains which continue to grow higher today.
The African plate pushed into Europe forming the _____.
In North America, the _______Mountains formed and the ___________ Plateau was uplifted.
geology of cenozoic era
The Atlantic Ocean continues to widen as new ocean crust is formed at the Mid Atlantic Ridge.
India collided with the Asian continent forming the Himalayan Mountains which continue to grow higher today.
The African plate pushed into Europe forming the Alps.
In North America, the Rocky Mountains formed and the Colorado Plateau was uplifted.
life forms of cenozoic era
M__________ became more diverse.The first _________evolved from chimp-like ancestors.
Mammals became more diverse.The first humans evolved from chimp-like ancestors.
climate of cenozoic era
Early Cenozoic climate was ______ and ______and the climate gradually _______ down.
Earth’s climate has cooled and warmed all throughout the cenozoic era
Early Cenozoic climate was warm and humid and the climate gradually cooled down.
Earth’s climate has cooled and warmed all throughout the cenozoic era
New mammal species evolved and were able to live in areas and eat foods that had been used by dinosaurs during the Mesozoic.
Cenozoic Era
Bats, rodents, owls, herons and eagles made their first appearance while crocodiles, turtles and frogs thrived in the tropics
Cenozoic Era
Snakes evolved rapidly as there was now an abundant food supply with the new rodents that had evolved.
Cenozoic Era
evolved and was well adapted to the cooler climates of the late Cenozoic.
Grass
_______ and other species of grazing animals evolved and ate the newly-evolved grass. The first _________ were small, about the size of a labrador retriever
horses
The land was dominated by tropical forests.
Deciduous and coniferous trees became dominant at higher altitudes and tropical forests retreated to the equatorial regions.
Cenozoic Era
cenozoic era
Modern humans and their recent ancestors are called _________.
hominids
cenozoic era
Thousands of fossils of hominids have been found; the oldest is more than ___ million years old.
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