Midterm Cards Flashcards
1
Q
were dinosaurs slow and stupid?
A
agile, got smaller over time
2
Q
did dinosaurs swim in the ocean?
A
no those are marine reptiles
3
Q
era of the dinosaurs
A
mesozoic era
4
Q
what are the periods of the dinosaurs
A
triassic, jurassic, and cretaceous
5
Q
______, Mesozoic, _______
A
Palaeozoic, mesozoic, Cainozoic era
6
Q
time if the mesozoic era
A
251-65 Ma
7
Q
Ma
A
megaanom= million years ago
8
Q
subdivisions of time
A
eons, eras, periods, epochs, ages
9
Q
when did most dinosaurs go extinct?
A
end of cretaceous: 65.5 Ma
10
Q
times of triassic, Jurassic, cretaceous
A
triassic: 251 Ma
Jurassic: 200 Ma
cretaceous: 145
end of cretaceous: 65.5
11
Q
geology
A
study of earths materials and earths hisrtory
12
Q
science
A
a changing body of knowledge obtained through systematic study and practice; a search for general laws of natural processes
13
Q
components of scientific method
A
1) observation establishes question
2) hypothesis developed
3) observation/ experiments to test hypothesis
4) last surviving hypothesis is the conclusion
5) accumulated body of knowledge = scientific theory
14
Q
fossils
A
any physical evidence of ancient life
15
Q
2 types of fossils
A
body fossils
trace fossils
16
Q
body fossils
A
direct evidence of body or body parts such as mineralized bones, or soft tissue (rarely)
17
Q
trace fossils
A
indirect evidence such as tracks (footprints), feces, skin imprints, etc
18
Q
body fossils vs trace fossils
A
- body fossils after organism has died
- trace fossils left continuously
- more trace fossils
19
Q
3 criteria to become a fossil
A
1) rapid burial = to avoid scavenging, erosion, or other damage
2) preserved= in soft sedimentary rocks that aren’t changed too much
3) fossilized= to protect body fossils
20
Q
dinosaur bone fossilization process
A
per-mineralized`
21
Q
permineralized
A
1) decay of organic material opens up pores in the bone
2) pores are filled with mineral precipitates
3) bone minerals are gradually replaced
22
Q
7 types of dinosaur fossils
A
1) bones and skeletons
2) eggs
3) gastroliths (gizzard stones)
4) feces (coprolites)
5) skin impressions
6) footprints and trackways
7) toothmarks
23
Q
other evidence and data used in interpreting dinosaurs (4)
A
1) living relatives (birds)
2) rocks
3) computer modeling
4) other fossil groups
24
Q
collecting specimens
A
- large and fragile bones
- exposed, if fragile then encased in plaster
- allows for safe removal to lab
25
preparing the specimens
bones prepared and reconstructed in lab, not the field
26
Mineral criteria (5)
1) naturally occurring
2) crystalline
3) solid
4) define chemical composition
5) inorganic (usually)
27
What is a rock?
Rock is a consolidated aggregate of minerals
28
3 types of rocks
Igneous, metamorphic, sedimentary
29
How to distinguish rocks
Mineralogy and texture
30
Igneous rock formation
formed from very hot liquid (molten rock - magma) that originated deep in earth and moved up towards surface
31
Types of igneous rock
Extrusion and intrusion
32
Extrusion igneous rock formation
Magma erupts on the surface and cools
33
Intrusion igneous rock formation
Magma stalls just below the earths surface and is later exposed
34
Sediment definition
Anything that gets moved
35
Timeline/process of sediments
- pieces break off (erosion)
- carried down by weather (transportation)
- dropped off somewhere (deposit)
36
Where does sediment often occur
Water becomes calmer, such as low-gradient river valleys, lakes or oceans
37
Why is sand a type of sediment
It’s a collection of broken down (weathered) materials transported from various sources: rocks and living things (shells, wood, bones)
38
Sedimentary rocks
As the sediments pile up, the earlier sediments are buried deeper, and are subject to high overburden pressure, and become more compacted. Various chemical changes take place, cementing the particles together, forming a sedimentary rock.
39
Lithification definition and steps
The process of comparcting and cementing
1) sediment build up
2) pressure build up from all the sediment
3) fused together to become rock
40
Metamorphic rocks
If sedimentary rocks are not uplifted, they can be buried deeper, and undergo chemical change due to higher temperature and pressures (a process called metamorphism). They then become metamorphic rocks.
41
What kind of rocks are these
Metamorphic (warping from the pressure)
42
What type of rock is this
Sedimentary (layers)
43
metamorphic rocks and mountains
Metamorphic rocks may also be uplifted to form mountains, then weathered and transported, etc. Otherwise, they may be buried deeper, then melted to magma (molten rock). Magma may be released to the surface as lava, forming a volcano.
44
label the rock cycle
a: weathering
b: transportation
c: deposition
d: sediments
e: lithification
f: sedimentary rocks
g: metamorphism
h: metamorphic rock
i: melting
j: magma
k: crystallization
l: igneous rock (intrusive)
m: solidification
n: igneous rock (extrusive)
o: uplift and exposure
45
what type of rocks is best to preserve fossils? and why aren't the others?
- sedimentary
- igneous is too hot (maybe igneous extrusive rock ex ash falling and preserving body)
- metamorphic has too much pressure and will break up specimen
46
bones as particles
- bones in a geological sense are just oddly shaped grains of sediment, part of the rock cycle.
- They can be picked up and carried by water, or simply can be buried by other sediments.
- Fossilization is part of the process of lithification of sediments.
47
articulated fossil
full body fossil
48
chunkasaurs
fragment/ part of bone/ articulate
49
rocks and what they tell us about their environment
- Sedimentary rock types reflect their environments of deposition.
- In rocks made up of transported particles, the grain size tells us the energy level of the environment.
- Clays indicate very quiet water (lakes, ponds), whereas sands suggest more energy and gravels even more (e.g., river channel).
-The layers themselves can show old river channels, sandbars, etc.
50
types of sedimentary rocks
low energy = clay/mud (when lithified is shale and mudstone)
medium energy = sand (sandstone when lithified)
high energy = gravel (conglomerate when lithified)
51
best type of sedimentary rock to preserve fossils
low energy (high energy would break up fossil)
52
characteristics of best terrestrial environment to preserve dinosaur fossils
1) on land
2) quiet water
3) rapid burial (mudslide, volcanic ash)
4) low energy
53
what are the layers of the earth by composition
crust (light)
mantle
core (heavy- made of metal: iron and nickel)
54
what are the layers of the earth by physical properties
lithosphere
asthenosphere
outer core
inner core
55
lithospheric plates
the lithosphere is broken into a number of large plates and many more smaller plates that move on the ductile asthenosphere
56
3 types of plate booundaries
1) convergent
2) divergent
3) transform
57
convergent boundary
come together- subduction and uplift
58
what type of boundary is this
convergent
59
divergent boundary
go apart - magma coming up (volcanoes)
60
what type of boundary is this
divergent
61
transform boundary
side by side - still get stuck then pressure builds up until it releases (earthquake)
62
what type of boundary is this
transform
63
plate techtonics
the action of plates (spreading, subduction, faulting) causes movement and tectonic activity (earthquakes, volcanism, mountain)
64
why is plate tectonic important
- continents are parts of large plates and move with respect to one another
- plate tectonics directly affects all of the processes of the rock cycle
- plate history is therefore important in understanding evolution, fossilization, and other topics - the earth has changed
65
when did the world look like this?
early triassic: 251 Ma
separated through Mesozoic
66
when did the world look like this?
late jurassic: 145 Ma
67
when did the world look like this?
late cretaceous: 65.5 Ma
68
mesozoic tectonics
- early in the mesozoic, all the continents are together and sea level was low
- late in mesozoic, all the continents are separated and sea level was vey high
- separated dinosaurs to cause more diverse breeding and more species
- dinosaur fossils can also be found in water because of rising sea levels
69
Taxonomy why
TO DESCRIBE NATURAL CATEGORIES
70
Systematics why
To help understand relationships
71
Systematics
Ordering the categories in terms of relationships (evolution), not just similarity
72
Taxonomy
The procedure of naming things
73
Linnaean system subgroups
Kingdom, phylum, class, order, family, genus, species
74
What is a species
Modern biological species are defines in terms of ability to interbreed under natural conditions
-bio species concept
- morphospecies concept
75
Biospecies concept
Reproduce viable offspring
76
Morphospecies concept
Use different morphology (shape/structure) as indirect evidence that they do not interbreed
77
Natural selection based off of what observation?
1) more offspring are produced than can survive to maturity
2) variations exist among the offspring
3) offspring must compete with one another for food, habitat, and mates
4) offspring with the most favourable characteristics are more more likely to survive to reproduce
5) beneficial traits are passed [on to the next generation
78
Survival of the _________
Best adaptable in that environment
79
Utility of fossils in the study of evolution
1) fossils are their only direct evidence for the history of life on earth
2) when we look at fossils, we see the appearance of structures and forms (adaptations) that separates genera, species, etc.
3) some characters change more with new genera than others
80
Homologous
Minilarity of organisms from different species doe to their inheritance from a common ancestor. Features that share such similarities are said to be homologous - similar from common ancestor
81
Analogous
Features show militarily in form but have a separate evolutionary history - similar but not from same recent ancestor
82
Cladistics
Takes on organism (with a set of characteristics) and classifies other organisms by the degree to which they resemble the first one
83
Cladogram
Shows clades (branches) of how similar organisms are
84
Evolutionary novelties
Organisms in a Claude are grouped by similar structures that are hypothesized to be evolutionary novelties (changes inherited from a common ancestor)
85
Cladistics: assigning characters
Characters need to be useful for distinguishing between organisms. If all organisms in an analysis possess the same character, it cannot tell us about their evolutionary relationships
86
Parsimony
The explanation with the least necessary steps is probably the best one
87
Monophyletic groups
Organisms that share a more recent common ancestor to each other than other organisms
88
what caused early mesozoic climate?
1) Pangea causes high seasonality
2) as Pangea starts to break up (rift), there is substantial volcanic activity that leads to high levels of CO2 in the atmosphere = a warmer world
89
high seasonality
hot summers and cold winters, less stable weather
90
the climate in the cretaceous
Pangea breaks p and high sea levels means a warm climate
- dinosaurs flourish at the poles
91
how would low diversity occur in dinosaurs?
In Pangea, dinosaurs can mix, leading to wide distribution of families
92
what drove the diversification of dinosaurs
Pangea breaks up and dinosaurs (and vegetation) change separately, causing isolation and diverse evolution of species
93
dinosaur food (plants)
ferns, sphenopsids, gymnosperms, angiosperms
94
plants and dinosaurs
angiosperms evolved late in Mesozoic, just when herbivore dinosaurs rapidly diversified. Coprolite (poop) fossils indicate some dinos ate these but also gymnosperms. Dinos, birds, mammals, and pollinators all likely affected plant evolution.
95
The cladogram leading to dinosaurs
notochord, chordates, pikaia, add calcefied skeleton, vertebrates, add jaw, add lobbed fin, tiktaalik, add 4 legs, tetrapods, frog, add amniotic egg, amniote, mammals (synapsids), add two holes in head, diapsids, snakes,add socketed teeth, add antorbital fenetra (holes). archosars, pterasaurs, dinosaurs
