catastrophism
todays geological formations result from catastrophic events in the past on a scale never observed today
uniformitarianism
geological processes taking place now worked similarly in the past
who is the “father of geology”
Hutton
relative dating
techniques for assigning relative ages to rock strata based on the relationships between newer and older rocks
what was used to create the geologic time table?
relative dating
examples of relative dating techniques
Hadean + Archean + Proterozoic =
Precambrian
fossils in the 1800s
viewed as products of supernatural forces
did everyone believe in extinction
fossilization requires …
species circumstances
why would a lack of fossils make it more difficult to understand evolution?
it would be more difficult to deduce the particulars about how life evolved
fossilization
variety of processes that enables the preservation of organic remains within the geological record
conditions of fossilization
rapid & permanent burial/entombment (fossilization)
protected specimen from biological disturbance
continued sediment accumulation (fossilization)
ensures organism remains buried
oxygen deprivation (fossilization)
limits decay
absence of excessive heat or compression (fossilization)
geological processes that can destry fossils
compression fossils
casts and molds fossils
fossil mold
unfilled space
fossil cast
new material fills the space
permineralized fossils
unaltered remains
weaknesses of the fossil record