exam 4 Flashcards
what is the definition of fossils
trees and remains of ancient organisms
the remains of once living organisms
what are the conditions for fossilization
not exposed
buried quickly
oxygen free
where scavengers cannot access & bacteria free
what are conditions that will NOT lead to fossilization
remains are left exposed for a long period of time
because scavengers will eat
and maggots will quickly consume the flesh
what are some examples of of ways that an organisms can be buried quickly upon death
under soil sediments deposited by water
how is the geological timescale information obtained?
By placing all past life forms - as rep. by organisms - on the geographical timescale - paleo’s record major changes and events in the evolution of plants and animals
what is stratigraphy
Stratigraphy is a branch of geology concerned with the study of rock layers and layering. It is primarily used in the study of sedimentary and layered volcanic rocks.
what is the geological timescale
Geologic Time Scale, also often known as GTS, is a method of determining when certain animals lived and their relationships to each other by examining rock layers and the fossils they contain.
when was the cenozoic era?
65 mya
what are the 7 epochs within the cenozoic era?
These are the 7 epochs within the cenozoic era and in order
1 - Holocene
2 - Pleistocene
3 - Pliocene
4 - Miocene
5 - Oligocene
6 - Eocene
7 - Paleocene
what are the two types of fossils
sedimentary ( common)
volcanic rock
holocene time frame in book
0 - 0.12 million years
pleistocene timeframe
0.12 million years - 2.6 million years
pliocene timeframe
2.6 - 5.3 million years
Miocene timeframe
5.3 - 23 million years
Eocene
34 - 56 mya
paleocene
56 - 66 mya
who is the first recognized tool user?
austrolopithecus garhi
what is cenozoic
era lasting from 66 mya until the present encompassing the radiation and proliferation of mammals such as humans and other primates
what is mesozoic
second major era of geologic time, 230 - 66 mya, characterized by the emergence and extinction of dinosaurs
what is paleozoic
first major era of geologic time, 545 - 66 mya, characterized by the emergence and extinction of dinosaurs
what is the criteria for radiometric dating
The method compares the abundance of a naturally occurring radioactive isotope within the material to the abundance of its decay products, which form at a known constant rate of decay.
what is characteristics define a hominin
bipedal locomotion
nonhoning chewing
preceded speech
material culture
what are the 7 distinguishing characteristics that are associated with bipedalism in the skeleton
foramen magnum is positioned on the bottom of the skull
the spine is s shaped
ilium is short from frornt to back
legs are long relative to the body trunk and arms
knees are angled inward
foot has a longitudinal arch
big toe is not opposable
what is the difference between honing and nonhoning chewing
primates have honing chewing, which means their large canines cut their food