Exam 1 Review Flashcards
1
Q
What is Scientific Inquiry?
A
- It has to be explanatory by reference to natural law
- It is testable against the empirical (natural) world
- its conclusions are tentative (not the final word)
- It is falsifiable
- It can do the “work”
2
Q
What is Idealism?
A
It explains that that are 2 coexisting worlds– one is idea, eternal and real; one is illusionary and imperfect (perceived by humans)
- developed by Plato; also referred to as essentialism
3
Q
Who is Plato?
A
Greek philosopher who developed the concept of idealism – he did not believe in evolution
4
Q
Who is Aristotle?
A
- Plato’s pupil
- recognized organisms vary from simple to complex
- proposed the scala naturae
- did not believe in evolution
5
Q
What is the Scala Naturae?
A
- a ladder of life where each organism occupies each particular rung
- every species was fixed and did not evolve
6
Q
Who is Nicolaus Steno?
A
- found fossilized shark teeth on top of mountains
- concluded that the earth must be very old and changed
7
Q
Who is James Hutton?
A
- Father of geology
- formulated theory of gradualism
- concluded that the earth is extremely old
8
Q
What is Gradualism?
A
- a profound change is the cumulative product of slow but continuous processes
- possible to explain present day geological formations by studying present day forces
9
Q
Who is Charles Lyell?
A
- author of Principles of Geology
- it is used to explain events in the past
10
Q
What is Uniformitarianism?
A
- processes acting now can be used to explain events in the past
11
Q
Who is Charles Darwin?
A
- proposed the theory of evolution by natural selection
12
Q
Who is Georges Cuvier?
A
- father of paleontology
- found the history of life was contained in fossil-bearing rocks deposited in layers
- recognized extinction
- did not believe in evolution
13
Q
Who is Linneaus?
A
- father of taxonomy and binomial nomenclature
- grouped species into hierarchies
- natural theologian
14
Q
Natural Theology
A
- attempt to reveal God’s plan by studying nature
15
Q
William Paley
A
- Author of Natural Theology
- developed the “watchmaker” metaphor
- natural theologian
16
Q
Richard Owen
A
- developed the concept of homology
- coined the term dinosaur
- developed the archetype
17
Q
Jean-Baptise Lamarck
A
- first evolutionist to propose a mechanism for how evolution took place
- two principles: use and disuse – those traits that were most used by an organism get bigger and stronger, & the that are not are discarded – traits can be passed down to offspring by the inheritance of acquired characters
18
Q
Thomas Malthus
A
- wrote “Essay on the Principle of Populations.” In nature, plants and animals produce far more offspring than can survive
19
Q
Who is Alfred Russel Wallace?
A
- Co-founder of evolution by natural selection along with Darwin
20
Q
What is Artificial selection?
A
- selective breeding of plants and animals to promote the occurrence of desirable traits in offspring
- Example) can produce different crops from a single common ancestor
21
Q
The law of succession
A
- the pattern of how fossils are deposited
22
Q
What are vestigial structures ?
A
- structure present in an organism that no longer serves the original purpose
- Example) human tailbone
23
Q
What is homology?
A
- similarity resulting from common ancestry
24
Q
What is developmental homology?
A
- similarities in the development of embryos between different species that share a common ancestor
25
What is molecular homology?
- similar DNA among different species from a common ancestor
26
What is biogeography?
- the pattern of distribution of organisms on earth
27
What are Darwin's first 3 observations and first conclusion?
1. All species have great potential for fertility. Populations would increase if all offspring survived and reproduced
2. populations of species normally display stability
3. natural resources are limited
1. Since more offspring are produced than can survive, there is a struggle for existence among populations
28
What are Darwin's last 2 observations and conclusions?
4. individuals vary in their characteristics
5. much of the variation is heritable
2. The struggle for existence is not random -- natural selection occurs
3. the inequality in survival / reproduction will lead to change in a population with favorable characteristics accumulating over the generations
29
What is natural selection?
- the only mechanism that results in adaptations and leads to increased fitness - - survival of the fittest
30
What is Modern Synthesis?
- the fusion of genetics with Darwinian evolution
31
What is a population?
- a group of individuals that belong to the same species and live in the same area
32
What is a gene pool?
all the genes, including all different alleles for each gene, that are present in a population at any one time
33
What is an allele?
- different forms of a gene
34
What is sexual recombination?
- crossing over and shuffling of genes during meiosis
- a source of genetic variability
35
What is evolution?
- a change in allele and genotype frequencies over time
36
What are the assumptions of Hardy-Weinberg?
1. no mutation
2. no migration (genetic drift)
3. random mating
4. no natural selection
5. large population size
37
What is the Hardy-Weinberg equation?
p^2 + 2pq + q^2 = 1
38
What is a mutation?
- ultimate source of genetic variability
- occurs constantly in DNA
39
What is gene flow (migration)?
- it is the movement of alleles from one population to another
- tends to eliminate genetic differences in populations by equalizing allele frequencies
40
What is Genetic Drift?
- a change in the allele frequency of a population as a result of random chance
- can be modeled by a coin toss
- pronounced in small populations
- leads to loss or "fixation" of alleles and can be intensified by a genetic bottleneck or colonization
41
What is a genetic bottleneck?
- temporary dramatic reduction in size of a population or species
- often caused by natural disaster
- reduces genetic variability
42
What is the founder effect?
- genetic drift that occurs when a few individuals become isolated from a larger population and form a new population whose gene pool composition is not reflective of that one of the original population
- exposes recessive alleles from non random mating increasing the number of homozygous individuals
43
What is inbreeding?
- mating between close relatives
- increases the number of homozygotes and reduces the number of heterozygotes
44
What is inbreeding depression?
- loss of fitness that takes place when homozygosity is increased due to inbreeding
45
What is fitness?
- the relative likelihood that a genotype will contribute to the gene pool of the next generation as compared with other genotypes
- the measure of reproductive success
46
What is directional selection?
- decreases diversity by favoring one extreme phenotype in the population
47
What is stabilizing selection?
- the decrease of diversity by favoring the average phenotype over both extremes
48
What is disruptive selection?
- the increase of diversity by favoring both extremes, and selecting against the average
49
What is sexual selection?
- occurs when individuals in a population differ in their ability to attract mates
- a form of non-random mating the DOES alter allele frequencies
- targets loci that code for mate choice traits and produces changes in allele frequencies
50
What is sexual dimorphism?
- differences in physical characteristics between males and females of the same species
- results from sexual selection
51
What is intrasexual selection?
- happens between members of the same sex
- males directly compete for mating opportunities or territories
52
What is intersexual selection?
- between members of the opposite sex
- female choice
- often results in showy characteristics from males such as bright colors of male birds
53
What is the fundamental asymmetry of sex
- female fitness is limited by an ability to gain resources required to produce eggs and rear young
- male fitness is limited by the ability to attract mates
54
What is species?
- the fundamental biological unit
- not fixed (they change)
55
What is speciation?
- occurs when ancestral populations are split in two and each population diverges from the other
- gene flow stops
- can be tested by taking individuals from each population and mate them to see if they can still interbreed
- the outcome of isolation and divergence
56
What is the biological species concept?
- based on reproductive isolation
- Alfred Russel Wallace and Ernst Mayr
57
What is the morphospecies concept
- based on identifying species that look different
- cells look different and have different # of chromosomes
- different species can use it on anything (bacteria, fossils, "easy to use")
Weakness -- things that look the same might be different species, things that look different might be the same species
58
What is hybridization?
- when two species mate and produce a hybrid offspring
- complicated the biological species concept (BSC)
59
What are the limitations of BSC?
- difficult to apply in real world
- cannot be applied to asexual or extinct organism
- does not account for genetic exchange in ring species
- does not account for hybridization in plants and animals
60
What is the ecological species concept?
- there is a one-to-one correspondence between a species and its niche
- improves the biological species concept
61
What is the evolutionary species concept?
- members of a species share common ancestry
- improves the biological species concept
62
What is pre-zygotic reproductive isolation?
occurs before fertilization
- behavioral (ie: two frogs do not recognize each other's mating call)
- time: temporal (ie: one frog mates in summer, one mates in spring)
- ecological (prefer slightly different ranges of habitat)
- habitat isolation (geographic barrier prevents contact)
- mechanical (size or incompatible genitalia prevents mating)
- gametic isolation (gametes fail to untie successfully. Important in species that release gametes into the water or air)
63
What is post-zygotic reproductive isolation?
occurs after fertilization
- genetic incompatibility usually leading to failure of the zygote to develop
- hybrid inviability (fertilized egg cannot progress past an early embryo)
- hybrid sterility (interspecies hybrid viable but sterile -- mule)
- hybrid breakdown (hybrids viable and fertile but subsequent generations have genetic abnormalities
64
What is isolation?
- created by reduction in gene flow
- causes speciation
65
What is divergence?
- created when mutation, genetic drift, and selection act on populations separately
- causes speciation
66
What is allopatric speciation?
the formation of a new species as a result of an ancestral population's becoming isolated by a geographic barrier
- vicariance (geographic separation)
- dispersal (migration)
67
What is co-speciation?
- when two groups of organisms speciate in response to each other and at the same time
- Example) gophers migrated and speciate, forcing their parasites to speciate
68
What is sympatric speciation?
- speciation without geographic isolation
69
What is instantaneous speciation?
- caused by hybridization between two species in which the offspring are reproductively isolated from both parents
70
What is polyploidy?
- in plants, the result of an extra set of chromosomes during cell division
- a type of sympatric speciation
71
What is allopolyploidy
- a species with multiple sets of chromosomes derived from different species
- type of sympatric speciation
- creates sterile but viable hybrid
72
What is nondisjunction?
- an error in meiosis or mitosis in which members of a pair of homologous chromosomes or a pair of sister chromatids fail to separate properly from each other
- creates tetraploid (fertile plant)
- type of sympatric speciation
73
What is a phylogenetic tree?
- a diagram that describes phylogeny
- a hypothesis of evolutionary relationships among carious species
- branches represent populations, nodes represent hypothetical ancestors that gave ride to two species
74
What are sister groups?
- they share a common ancestor not shared by any other group
- a phylogenetic tree is a set of these relationships
75
What does monophyletic mean?
- pertaining to a taxon derived from a signed ancestral species that gave rise to no species in any other taxa
76
What does paraphyletic mean?
- pertaining to a group of taxa that consists of a common ancestor and some, but not all, of its descendants
77
What does polyphyletic mean?
- pertaining to a group of taxa derived from two or more different ancestors
78
What is taxonomy?
- the hierarchical system involving successive levels
- discovered by Linneaus and reinterpreted by Darwin
- each group is called a taxon
79
What is a domain?
- a classification in taxonomy
- most inclusive group
- all of life belongs to one of the 3 domains (bacteria, archaea, and eukarya)
80
What is phylogeny?
- reflects the hierarchical taxonomic system of linneaus
-domain--kingdom--phylum--class--order--family--genus--species
81
What is homology?
- the similarity resulting from common ancestry
- used to build phylogenetic tree
82
What is analogy?
- superficial similarity, often due to convergent evolution (amphibians having fins but not being fish; bats having wings but not being birds)
83
What is apomorphy?
- derived character state (a trait)
84
What is synapomorphy?
- shared derived character state (a trait)
- you can group them
85
What is the out group?
- characteristics you're interested in connecting in a phylogenetic tree
86
What is Occam's razor?
- the simpler explanations that are more likely to be true than complex ones
87
What is the fossil record?
- only record we have of extinct forms
- allows us to calibrate phylogenies in terms of Tim e
-places evolutionary events in context with earth's histroy
88
What are the fossil record bias?
- easier for common things
- hard parts
- aquatic things
- more recent things
- more widespread things
89
What is mass extinction?
- an event during which many species become extinct during a relatively short period of time
