Evolutionary Biology Lecture 2

Front 1

Evolution

Back 1

When differences arise within a population of descendants of one ancestor

Front 2

Theory

Back 2

One or more linked coherent statements or explanations confirmed by observation and experiments and have withstood attempts at disproving them

Front 3

Inheritance of Acquired Characteristics

Back 3

Changes in physiology from frequent use are passed on to offspring until reaching the "ultimate form" or limit of development

Front 4

Spontaneous generation, variations between siblings, common ancestry

Back 4

What doesn't inheritance of acquired characteristics explain?

Front 5

1. Two species of Rhea in separate regions of S. America

2. Galapagos finches

3. Fossils of extinct llama-like ancestor in S. America

Back 5

What are three of Darwin's clues on the voyage of HMS Beagle?

Front 6

Natural Selection

Back 6

Beneficial traits of an organism are selected by environmental pressures

Front 7

1. No individuals alike

2. Wallace's Line

3. Malthus' essay

Back 7

Key observations made by Wallace

Front 8

Wallace's Line

Back 8

Deep channel restricted movement during low levels when Sumatra, Borneo and Java joined with the mainland and Australia was connected to New Guinea

Front 9

Origin of a Species

Back 9

Book written by Darwin and presented at the Linnean Society in London

Front 10

1. Common ancestry

2. Natural Selection

Back 10

2 Main Ideas of Origin of a Species

Front 11

Darwin: Variations in pops, favorable variations survive, life diverged from single common ancestor, evolution gradual

Lamarck: Species arise spontaneously, progressed from simpler to more complex, ignores variations in pops, doesn't explain extinction

Back 11

Contrast Darwin and Lamarck

Front 12

Particulate Inheritance

Back 12

What did Mendel call his studies in genetics?

Front 13

1. Different arrangements of chromosomes in Metaphase I

2. Crossing over in Meiosis I

3. Mutations and inaccuracy of DNA replication

Back 13

Three Sources of Genetic Variation for Natural Selection

Front 14

New Synthesis

Back 14

Term coined by Julian Huxley of combination of mutation and natural selection causing evolution in populations

Front 15

Neutral Theory of Molecular Evolution

Back 15

Evolutionary changes result from genetic drift and do not influence fitness of organism

Front 16

Molecular Clock

Back 16

Mutation rate of gene or protein is constant over time and closely related species have fewer mutations between them

Front 17

Fossil

Back 17

Preserve remains or traces of organisms usually formed through mineralization, compression or molds

Front 18

Permineralization

Back 18

Process of fossilization in which mineral deposits fill internal spaces of an organism

Front 19

1. Population size of organism

2. Body parts usually hard

3. Rapid burial

4. Location is marine

5. Layer remains intact

Back 19

Factors influencing fossil formation

Front 20

1. Existence and disappearance of organisms

2. Periods of diversification

3. Movement of continents and distribution of organisms

4. Climatic or environmental changes

Back 20

Fossils Show:

Front 21

Taphonomy

Back 21

Study of fossils and how they become fossilized

Front 22

Radioactive dating

Back 22

Unstable elements decay and we measure their half-life

Front 23

Strata

Back 23

Layers of sediment deposited at different times

Front 24

Cyanobacteria, stromlites

Back 24

Earliest microfossils

Front 25

1. Too complex

2. Phylogenetically come too late

Back 25

Why are cyanobacteria not the first life forms?

Front 26

Biomarkers

Back 26

Compounds unique to each domain that are preserved in sediment and used with radiometric dating to indicate presence of baceria, archaea and eukaryotes

Front 27

Fossil biomechanics

Back 27

Biomechanical studies to predict behavior from morphological information

Front 28

Sarcopterygian

Back 28

Early tetrapod

Front 29

Synapsid

Back 29

Mammal ancestor

Front 30

Osteolepiforms

Back 30

Paired fins, inflexible head, five-digit limbs

Front 31

Clade

Back 31

A group consisting of a single organism and all of its descendants

Front 32

Cladistics

Back 32

Study of systematics classifying living organims on basis of shared ancestry

Front 33

Linnean Taxonomy

Back 33

Classifying organisms together based on morphological similarites

Front 34

Cope's Law

Back 34

Median rate of change= Change from original/# of generations

Front 35

Central Dogma

Back 35

DNA--->RNA------>Amino Acid

Front 36

Stanley Miller

Back 36

1950s experiment replicated conditions of early Earth and produces purines, pyrimidines, amino acids, sugars and lipids

Front 37

Tom Cech

Back 37

RNA ribozyme can link amino acids together to form protein without rRNA or tRNA

Front 38

Replicated slowly and less accurately, only had RNA and lipid membranes

Back 38

What did org's look like in RNA world?

Front 39

Pre Cambrian atmosphere

Back 39

Anaerobic atmosphere, landscape dominated by stromalites inhabited by cyanobacteria

Front 40

Iron bands

Back 40

What geological indication exists of an oxic atmosphere created 2.2 BYA

Front 41

Endosymbiosis

Back 41

Archaean acquired a mitochondria

Front 42

1.5 BYA

Back 42

First eukaryote fossil found when?

Front 43

640 MYA

Back 43

First multicellular eukarotes appeared when?

Front 44

Edicaran fauna

Back 44

First multicellular eukaryotes

Front 45

Cambrian Explosion

Back 45

Evolutionary event that created nearly all the modern phyla of skeletonized marine animals

Front 46

Bilateria

Back 46

Organisms with bilateral symmetry present by end of Cambrian

Front 47

Burgess Shale

Back 47

Place with many fossils of Cambrian explosion

Front 48

Palezoic: Ordovician and Silurian

Back 48

Period where 21 classed of echinoderms appear and are epifaunal and first land plants

Front 49

1. Dessication

2. Varying temperatures

3. UV radiation

Back 49

Adaptations for first land plants

Front 50

Charales

Back 50

Order of first land plants

Front 51

Paleozoic: Devonian

Back 51

Era with first tetrapods and marine millipedes come to land

Front 52

Paleozoic: Carboniferous and Permian

Back 52

Era when seed plant diversified, amphibians and winged insect diversified, Pangaea formed, reptiles arrive

Front 53

Permian Extinction

Back 53

Greatest mass extinction where 96% species died

Front 54

Mesozoic: Triassic, Jurrasic and Cretaceous

Back 54

Split Pangaea, dominated by gymnosperms, first angiosperms, increased diversity of insects, diapsids most diverse group and dinosaurs diversed. Synapsids show up

Front 55

Laurasia and Gondwanaland

Back 55

Two splits of Pangaea

Front 56

The Cenozoic: Tertiary and Quaternary

Back 56

Era when N. America separated from Europe angiosperms, birds, mammals and snakes diversified. Period of Pleistocene

Front 57

Pleistocene

Back 57

1.8 MYA when changes in global temps lowered sea levels and linked N. America and Siberia, New Guinea and Indonesia joined to Asia and allowed movement of terrestrials

Large mammals became extinct from human hunting