More History of Life Stuff! Flashcards
When did modern humans first appear?
100-150 kya
_______ are pieces of evidence of organisms that lived in the past.
Fossils
What are the types of fossils?
Preserved Remains
Trace Fossils
Cast Fossils
Mold Fossils
Petrified Fossils
Carbon Film
A type of fossil where an impression or negative image of an organism is made in a substance and is then preserved. Example: shells
Molds
A type of fossils that forms when a mold is filled in by minerals from sediments and groundwater. Example: bones and teeth
Casts
A type of fossil that forms when an organic material is converted into stone. Example: coal balls and fossilized trees
Petrified
A type of fossil that forms when remains are preserved wholly. Example: mosquitos in amber, and Wooly Mammoth from the Siberian Ice
Original Remains
A type of fossil that forms when a carbon impression of an organism is made in sedimentary rocks. Example: leaf impressions on rocks
Carbon Films
A type of fossil that records the movement and behaviors of organisms. Example: trackways, tooth marks, gizzard rocks, coprolites (fossilized dungs), burrows and nest
Traces/Ichnofossils
The Six Ways of Fossilization
Unaltered Preservation
Permineralization/Petrification
Replacement
Carbonization/Coalification
Recrystallization
Authigenic Preservation
A way of fossilization: a small organism or part is trapped in amber, which is a hardened plant sap
Unaltered Preservation
A way of fossilization: the organic contents of bone and wood are replaced with silica, calcite, or pyrite, forming a rock-like fossil
Permineralization/Petrification
A way of fossilization: hard parts are dissolved and replaced by other minerals, like calcite, silica, pyrite, or iron
Replacement
A way of fossilization: the other elements are removed and only the carbon remains
Carbonization/Coalification
A way of fossilization: hard parts are converted to more stable minerals, or small crystals turn into larger crystals
Recrystallization
A way of fossilization: molds and casts are formed after most of the organism have been destroyed or dissolved
Authigenic Preservation
What are the two ways of dating fossils?
Relative Dating and Absolute Dating
This type of dating fossils does not tell the exact age; it compares a fossil as older or younger in context with other fossils depending on their position in the rock layer/s.
Relative Dating
This type of dating fossils tell the exact age of fossils using radioactive isotopes such as Carbon-14 and Potassium-40 with the their respective half-lives used as reference.
Absolute Dating
What are the rules of relative Dating (only the ones discussed by Niko-sensei)
what the fuck
Law of Superposition
Law of Original Horizontality
Law of Cross-Cutting Relationships
A rule of relative dating: when sedimentary rock layers are deposited, younger layers lay on top of older deposits
Law of Superposition
A rule of relative dating: sedimentary rock layers are deposited horizontally. If they are tilted, folded, or broken, it means that it happened earlier.
Law of Original Horizontality
A rule of relative dating: if igneous intrusions or a fault cuts through existing rocks, the intrusion/ fault is YOUNGER than the rock it cuts through.
Law of Cross-Cutting Relationships
How did the first living cells appear?
- abiotic synthesis of organic molecules.
- joining of these small molecules into macromolecules
- packaging of these molecules intro protocells
- formation of the origin of self-replicating molecules
