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1
Q

What traits evolve … (according to darwin)

A
  • must be inherited (lamark was wrong)
  • must show variation between individuals (inbreeding reduces variation
  • environment must exert some pressure on the traits (some variants must provide an advantage or disadvantage)
2
Q

three types of finches

A

cactus eater, seed eater, and insect eater (each had varied beak size

3
Q

Darwin’s evidence came from

A

homology, embryology, vestigial structures, biogeography, paleontology, comparative anatomy, and selective breeding

4
Q

structural genes

A

code for structurally important molecules (hox genes, sonic hedgehog)

5
Q

regulatory genes

A

code for structurally important molecules (proteins, fibers, etc.)

6
Q

epigenetic and inductions

A

tissue-tissue interactions that have demonstrable effect on morphologies (ex: teeth)

7
Q

genes encode for instructions of how to make RNA , RNA is read to produce what?

A

proteins, hormones, etc… the raw materials for tissue , organ, etc production

8
Q

homeotic gene influence (hox genes) do what?

A

mediate epigenetic interactions

  • also known as pattern formation genes
  • segmentation genes for example
  • serial homology (similar structure bc common ancestor)
  • forelimbs/hindlimbs
9
Q

___ genes are found in all segmented animals

A

homeotic

10
Q

homeobox genes are found in…

A

arthropods (+annelids), vertebrates (many vertebrate HOX genes are found with drosophila primers)

11
Q

Genotype

A

make phenotypes! are defined as simple traits, single genes, or whole chromosomes (sex determination)
two allele- one from the mother and one from the father

12
Q

phenotype

A

outward manifestation of the genotype –> physical traits, enzymes, etc… xx female genotype = female phenotype, xy male genotype = male phenotype, 50 percent probability either gender

13
Q

what are the three types of alleles in the ABO blood system?

A

recessive, dominant, and co dominant

individuals have two alleles

14
Q

dominant allele

A

The allele posssed in a heterozygote

15
Q

co dominant allele

A

when both alleles are expressed in a heterozygote

16
Q

recessive

A

the allele that is not expressed in a heterozygote

17
Q

obesity is a …

A

complex interaction between genes, environment, and phenotype, there are 32 genes associated with obesity

18
Q

gregor mendel

A

plant experiments… established the idea of particulate inheritance (no blending) but NOT ALL TRAITS ARE MENDELIAN… discovered dichotomous variation..

19
Q

mendel’s postulates about inheritance (1)

A
  1. hereditary characteristics are controlled by particulate unit factors that exist in pairs in individual organisms
    - traits remain discrete (not diluted over time)
    - because now we know their genes and the exact sequence of genes is preserved through generations
20
Q

Mendel’s 2nd postulate

A

when an individual has two different unit factors responsible for a characteristic, dominant (expressed) recessive (not expressed) —> recall some phenotype traits are influenced by multiple genes

21
Q

Law of segregation

A

no bias between maternal and paternal source

22
Q

law of independent assortment

A

features are passes onto offspring individual of eachother

23
Q

linkage

A

genes found on same chromosome closer = more linkage

24
Q

crossing over

A

makes possible the independent assortment of linked genes

25
Q

point mutation and sickle cell disease

A

whena single base in a gene is changed

26
Q

trinucleotide repeat disease

A

insertion mutation or deletion of several bases in sequence of a gene. EX) huntington disease caused by CAG repeat (code for glutamine) 40-180 tiems on chromosome 4, autosomal dominant disorder

27
Q

mutations can be

A

can be bad good or neutral.
bad = reduce ability to function causing mild reduction in fitness with lethal results
neutral = no change in protein form of function or slight changes with no effect on reproduction
good = increase “”

28
Q

x linked disorders

A

result from mutations to genes on x chromosome - males more prone because 1 x chromosome… colorblindness, hemophilia, etc…

29
Q

examples of medelian genetics in humans

A

widows peak, dimples, earlobes, darwins tubercle, hairy back , ptc

30
Q

two types of non medelian genetics

A

qualitative variation: discrete, present/absent, two/four

quantitative variation: continuous, color, size, gradient differences

31
Q

natural selection is defined as

A

The primary mechanism of evolution

32
Q

other types of natural selection include

A

directional, diversifying, stabalizing

33
Q

directional selection

A

selection pressure against one end of the population curve, results in a shift of the bell curve in one direction –> any variable.. size, color, etc

34
Q

diversifying/disruptitive selection

A

against the middle of the bell curve, promotes success at either end of the curve

35
Q

stabalizing selection

A

selection against both ends resulting in more homogeneous population –> common in generations after speciation events

36
Q

the modern (evolutionary or genetic) synthesis

A

meetings to discuss why geneticists believe natural selection was wrong and why random selection was correct

37
Q

what are some other mechanisms of evolution

A

gene flow, genetic drift, founder effect, and sexual selection

38
Q

gene flow

A

movement of genes between populations

39
Q

genetic drift

A

random change in frequency of a populaiton

40
Q

founder effect

A

genetic bottleneck

41
Q

sexual selection

A

differential reproductive success with one sex of any species

42
Q

More about gene flow (alleles)

A
  • movement of alleles among a population

- alleles can be transferred through movement of fertile individual gametes (pollen)

43
Q

gene flow tends to…

A
  • reduce differences between populations over tiem
  • is more lilkey than mutation to alter allele frequency –direction
  • can decrease the fitness of a population
44
Q

with genetic drift, the smaller the population…

A

increased chance of deviation from a predicted result

45
Q

genetic drift…(alleles)

A
  • describes how allele frequency flucuates unpredictably
  • tends to decrease genetic variation
  • random change in population, thus unpredictable…so not due to natural selection
46
Q

founder effect

A
  • occurs when a few individ. become isolated from a bigger population
  • allele frequency in the smaller population can be different from those in parent population
  • new populations derived from bigger population not representative of original, parent population
47
Q

bottleneck effect

A

sudden reduction in population size due to change in environment
resulting gene pool may no longer be reflective of original population gene pool
if population remains small, it may be affected by genetic drift

48
Q

sexual selection

A

mate choice is not equally balanced

  • typically the less common gender can choose from among many possible mates
  • most species maintain 1:1 gender ration under normal conditions
  • transiet differnce in sex ratios can have long term effect
  • choice of features can result in significant changes in opposite sex (anatomy, behavior, etc.)
49
Q

sexual dimorphism

A
typically a result of sexual selection 
different morphology (anatomy) between two genderes 
females exhibit choice more often than males resulting in unusual male morphologies
50
Q

examples of dimorphism in class

A

peacocks: symmetry, handicap, survival
orangutan: size and facepads (secondary sex characteristic)
elephant seal: size/nose

51
Q

how is sexual selection affected by social structure

A

polygamy and monogamy

52
Q

polygamy

A

mating is promscious without strong pair/bonds
sexual dimorphism common
promiscuity is hormonally reinforced

53
Q

monogamy

A

1 male and 1 female
sexual dimorphism not common
monogamy hormonally reinforced
selected for…

54
Q

biological species concept: who? and what is it?

A

ernst mayr
any two or more animals capable of potentially interbreeding to produce fertile offspring and are reproductively isolated from other such group in nature

55
Q

problems with bio species concept

A

not typically practicable - observable - in life
no concept of time (not possible to introduce a test if you try)
asexual species

56
Q

phylogenetic species who and what?

A

GG Simpson

common ancestry defines the species lineage evolving independently of other species

57
Q

problems w phylogenetic species

A

gray - how much difference is enough to warrant species distinction ?
exploitable

58
Q

genetic species definition + prob

A

presence of unique alleles in a population

may or may not correspond w phylogenetic species and how many??

59
Q

ecological species who + what

A

leigh van valen
niche defines the species (comparative in nature)
a set of organisms adapted to a particular niche in environment

may or may not form monophyletic group
possess discrete phenetic clusters that we recognize as species because ecological and evolutionary pressures

60
Q

recognition/ mate-recognition species concept

A

essentially mediated by mating behavior or biology

identified after the fact

61
Q

morphological species

A

based on morphological distinctions
may be from molecular or whole anatomy
…most common, paleontological species

62
Q

reticulate species concept

A

a species breaks apart and becomes many species and then may re-form into a single species or possibly multiple species
- occurs constantly at all scales of space and time

63
Q

isolating barriers - two types

A

geographic: extrinsic properties of landscape that prevent gene flow - allopatric - sympatric - parapatric

reproductive: features of organisms that prevent interbreeding
- barriers effective even in sympatry
- pre/ post-zygotic or pre/post-mating

64
Q

pre zygotic isolation mechs

A

ecological, behavioral, temporal, mechanical, (all pre mating) and gametic (post mating)

65
Q

ecological isolation

A

tions/ligers do not occur in wild

lion and tigers rangers overlap in india but they use different habitats

66
Q

behaviorial isolation

A

blue-footed boobies select mates after elaborate courtship display
will not mate with other boobies

67
Q

temporal isolation

A

hybrids can be made experimentally and are fertile

rare in nature because mating seasons differ

68
Q

mechanical isolation

A

structure of male and female copulatory organs may be incompatible

  • known in plans and animals
  • domestic breeds create greater diversity than found in the wild
69
Q

gametic isolation

A

external fertilzation. promotes gametic isolation (ex = fish)
surface factors and binding sites may prevent fusion of gamete

70
Q

post zygotic isolation mechs

A

intrinsic: hybrid inviability, hybrid sterility, and hybrid breakdown
extrinsic: ecological inviability, behavior inviability

71
Q

hybrid inviability

A

weak, malformed, non-function

72
Q

hybrid sterility

A

mules! chromosome number problem, acromosomal reaction fails, abnormal reproductive anatomy, dysfunctional gamete

73
Q

hybrid breakdown

A

F2’s and later.. multiple causes of reduced viability

74
Q

ecological inviability

A

can be easily seen, like a liger in a tiger habitat

75
Q

behavioral inviability

A

mating ritual doesn’t work

76
Q

speciation

A

the evolution of new species –> diversification

77
Q

pied flycatcher example

A

pied flycatcher and collard flycatcher appear very similar where they occur alone

in areas where they are sympatric, differences in color and pattern allow individuals to avoid hybridizing

78
Q

geography of speciation

A

species is a two part process:

  1. initially identical population must diverge
  2. reproductive isolation must evolve to maintain differences
79
Q

homogenizing effect of gene flow…

A

erases differences

80
Q

speciation more likely in …

A

geographically isolated populations

81
Q

three types of speciation

A

sympatric, parapatric, and allopatric

82
Q

john maynard

A

developed first mathematical model for sympatric speciation by assortative mating among ecological morphology.
- one gene per trait model with three genes and three traits
1. ecological perfomance
2.resource choice
3. choice of mating sites
he demonstrated its difficult to create and maintain associations between matcing alleles at three gene loci because re-mixing

83
Q

rhaogletis example

A

flies co evolved with plants : apples, etc..

84
Q

why is sympatric speciation rare? what is needed?

A

problem is how to avoid intermediate genotype that will function as bridges for gene flow which would eliminate difference.

  • need: polymorphism and assortative mating (look alike)
  • problem: if these two are not genetically couple, recombination will eliminate the barrier to gene flow
85
Q

euhadia shairs example

A

mutation in one gene –> shell spirals in opposite direction

= instant mechanical isolation = 2 species

86
Q

subspecies

A

common throughout bio, an identifiable subunit of species (+/- = race.. but politically charged term)

  • often geographically based, multiple unique traits, must have at least two
  • subspecies are in the “eye of the beholder”
  • … may be made-up of multiple populations
87
Q

Deme

A

generally a subset of species or subspecies ( = population defined by genetics)
- population density, western hemisphere. note that political boundaries are largely arbitrary

88
Q

population

A

generally a subset of species or subspecies that is identifiable based on some quantitative or qualitative criteria

89
Q

recording human variation in past civilizations

A
  • ancient Egyptian : recognize physical differences
  • ancient greeks: Ethiopians = dark-skinned
  • ancient roman: very little biological difference among its people
90
Q

Monogeism-Polygenism Debate (about 18th to 19th century)

A

monogeism = all people of all races = single creation
polygenism = different races = terms of own evoltuionary history
environment = environment has power to shape anatomy of individual organisms
DARWIN KILLS DEBATE

91
Q

RACE/RACISM

A

racism = a prejudicial belief that members of one ethnic group are superior in some way to those of another

92
Q

Later in the 20th century - Franz Boas

A
phenotypic plasticity ( growth and sleep)
lack of relationship between race and achievement
93
Q

Biology of Ethnic (Racial) feature-

A
  • skin color
  • eye form
  • hair color + form
  • head shape
94
Q

population genetics

A

study of genetic variation within and between groups of organisms

95
Q

microevolution

A

study of evolution phenomena that occur within species

96
Q

polymorphisms

A

ABO and other blood type systems

- two or phenotypes

97
Q

maternal-fetal incompatibility

A

Human leukocyte antigen (HLA) system

98
Q

A, B, AB, + O

A

first found during crimean war (1854-1856) British army surgeon kept records of successful blood transfusion

99
Q

Both A B have

A

antigens (carbs) , O = no

100
Q

antigen

A

stimulates immune response , especially production of antibodies produced by plasma B cells….

101
Q

Gene flow and morphology

A

complex genetics of morphological traits makes gene flow studies problematic
- some traits = simply inherited = good for study = tooth shape and form

102
Q

polymorphism and phylogenetics studies

A

phylogeny = an evolutionary tree indicating relatedness and divergence of taxonomic groups

  • sample quality is critical
  • polymorphisms can confound poorly sampled studies
103
Q

evolution of lactose tolerance

A

genetics of lactose tolerance:
lactose/lactase
lactose/ malabsorbers
LCT *P

104
Q

Explanations for lactase polymorphism

A

cultural historical hypothesis

lactose tolerance is an example of the interaction of biological and cultural factors

105
Q

balanced polymorphism

A

sicke cell & other conditions
sickle cell = heterozygous advantage (fights malaria)
OTHERS: tay-sachs disease and cystic fibrosis

106
Q

acclimization

A

the process of term changes in physiology that occu in response to changes in environmental changes

107
Q

adaptability

A

ability of organism (individuals) to make changes after chronic exposure to stressful environmental and conditions - AKA phenotypic plasticity

108
Q

parapatric speciation

A

speciation without complete geographic isolation and no clear isolation mechanism
no geographic barrier… speciation takes place on edges

109
Q

clinal variation

A

ring species clinal variants, and sometimes several parapatric speciation events
ex) bears..

110
Q

ring species

A

populations at end can no longer interbreed

ex)mountains

111
Q

cladogenesis

A

speciation characterized by diversification and increased species number (branching)

112
Q

anagenesis

A

essentialy “chronogensis” that results from accumulated change through time in a single lineage

113
Q

Tempo and Mode..

darwin expected..

A

gradual divergence of species… lyell’s uniformitarianism influence. (sympatric/allopatry)
selection pressure = low

114
Q

punctuality equllibrium

A

(eldridge + gould) is the rapid divergence of species followed by periods of relative stasis
-hopeful monsters analogy
-hox genes
selection pressure = high

115
Q

direct fitness

A

number of copies of genome left in the next generation

116
Q

indirect fitness

A

total including not immediate fam, nieces, nephews , etc..

117
Q

inclusive fitness

A

direct + indirect fitness . explains appearance of group selection, atruisim, etc.

118
Q

adaptation verb + noun

A

v: process by which inherited characters evolve in a population resulting in improved performance
n: a trait that has a functional role in life history of an organism and is maintained by natural selection

119
Q

Enhance evolutionary fitness ( + maybe survival)

A

mathematical measure of genes contributed to subsequent generation

120
Q

human adaptations examples

A

dark skin: in tropics = screens out UV radiation, reduces folate destruction, prevents sunburns, reduces risk of skin cancer

light skin: outside tropic = admits UV radiation, helps synthesize vitamin D, prevents rickets and osteoporosis

121
Q

adaptationists

A

every feature is adaptive (now or in past) they’re wrong = spandrels of st. marco

122
Q

biological spandrel exampels

A

human pelvis (holes), farm fox experiment (fur = not adaptive), music

123
Q

adaptive radiationists

A

closely related species that have evolved from a common ancestor by adapted to different parts of the environment —>occurs = evolutionary innovations // in an environment with few species and many resources

124
Q

natural selection acts at the level

A

of individuals.

group selection doesn’t really occur, though it can look like it does

125
Q

fitness

A

mathematical calculation of an individual reproductive contribution to the next generation
1 diploid offspring = 0.5 , 2 - 1.0 , etc…

126
Q

why do we study non human primates

A

behaviors are universal among modern primates and give us clues to our ancestors’ behavior –> allows the reconstruction of social structure, ecology, and intelligence of early humans.

compare and constrast primate social organization, communication, and intelligence –> interesting and my shed light on human diversity

better understand the environment factors that led to the divergence of the human lineage. —> environment affect behavior, and human culture exhibits diverse behaviors.

conservation of nonhuman primates NHPs

127
Q

the evolution of behavior (3)

A

behavior has evolved through natural selection
- brain structure, organization, etc..

individuals act to maximize their own reproductive success - evolutionary success

behavior is the product of complex interactions between genetic and environmental factors - polymorphisms, environmental plasticity, etc..

128
Q

studying primates

A
captive study (zoo)
semi free ranging (jane goodall, food= affects behavior and time budget) 
field study (no provisioning) (lose group)
129
Q

allogrooming (contrast: autogrooming)

A

reinforces male-female mate bonds
reinforces same sex friendships bonds
measurable physiological effects on both the individual being groomed and the one doing the grooming

130
Q

Promiximate causes

A

hormonal or physiological reason to act

131
Q

ultimate causes

A

deeper, evolved strategies that have been shpaed over millions of years of natural and sexual selection

132
Q

two paradigms of studying primate behavior

A

socioecology and sociobiology

133
Q

important primate behavior

A
dominance 
communication
aggression 
affiliative 
reproducing and reproductive strategies
mothers and infants
NHP cultural behaviors (crab eating macacks) 
primate cognitive abilities
134
Q

socioecology

A

relationship between social behavior and natural environment. Favors select for the individuals daily survival.

135
Q

sociobiology

A

focuses on the genetic predisposition to behaviors and those behaviors’ enhancement of reproductive success.

136
Q

evolutionary fitness

A

a component of sociobio. a quantification of reproductive success (% of genes left in generation)

137
Q

natural selection acts on behavior…

A

the same way it acts on physical characteristics

138
Q

behavior

A

is a phenotypic expression and genes may code for specific behaviors. directly or indirectly through neurological features.

provides opportunity to show the effects natural selection has had in shaping primate behavior.

139
Q

Case study (sociobiology)

A

3 monkeys allogrooming

140
Q

altruism

A

an action which increases (or potentially increases) someone else’s fitness while placing one’s own at risk
FAKE
genes… who else has our genes?
what effect does helping them have

141
Q

inclusive fitnesss

A

the total effect an individual has proliferating its genes

142
Q

coefficient of relatedness

A

the proportion of genes you share with a relative

ex) siblings 50%, cousins 12.5%

143
Q

kin selection

A

the behavior associated with being altruistic preferentially toward relatives

144
Q

socioecology

A

primatologists consider the following factors:
quality and quantity of different factors
distribution of food sources (relative with other species
activity patterns (diurnal v nocturnal)
relationship with other species
impact of human activities

145
Q

environmental factors such as resource availability and predation

A

have strong influence on group size and structure

  • multimale/female groups have an advantage when predation pressure is high
  • adult males may join forces and chase and attack predators
  • savannah baboons have been known to kill domestic dogs and attack leopards or lions
146
Q

solitary forging may be related to…

A

diet and distribution of resources or predator avoidance

147
Q

social behavior and reproductive asymmetry

A
femae philopatry (committment is longer)
male philopatry
148
Q

male reproductive strategies

A

dominance
have priority access to food and mating partners
many factors influence dominant status: sex, age, level of aggression, time spent in group, intelligence, motivation, and mother’s social position

149
Q

female reproductive strategies

A

dominance

sexual receptivity signals

150
Q

why are NHP social?

A

PARADOX OF SOCIALITY

  • access to mates
  • food
  • avoiding predators

CONS = competition and altruism rewarded.

151
Q

types of NHP societies

A
solitary
monogamy
polygamy
fision-fusion polygamy (no pair bonding) (baboons at seasonal plant site)
polyandry
152
Q

poly andry

A

many males one female

153
Q

primate origins

A

+/- mya (plesiadapis)

154
Q

extant taxa

A

+/- 300 species of nonhuman primates are recognzied

size and form vary greatly

155
Q

anatomical traits

A

grasping hands and opposable thumbs and big toes
flattened nails instead of claws
forward facing eyes with stereoscopic vision
generalized body plan
generalized teeth
petrosal bulla (hearing)

156
Q

life history traits

A

single offspring
large brains - encephalization and neocortex
extended otegeny - lifecycle
sociality living in grups

157
Q

behavioral traits

A

Activity patterns: diurnal, nocturnal, crepuscular (active during dawn and dusk)

158
Q

sociality

A

living in groups

highly territorial

159
Q

synaptomorphies (aka PROMISIANS)

A

Tooth grooming
grooming (toliet) claw
ansa coli (fermentation)
other : dental formula 2133/3133

160
Q

lepilemurs

A

26 sp nocturnal, arboreal, hoppping

161
Q

lemuridae

A

24 (+/- sp) diurnal, arboreal/ terrestrial, generalists

162
Q

indriiae

A

19 sp VCL 2123/2123

163
Q

DAUBENTONIIDAE

A

ONE SP,continuous incisor growth, omnivore, crepuscular, solitary

164
Q

galagos and bushbabies

A

nocturnal, ominvore, small family groups or solitary

165
Q

haplorhines

A

dry nosed primates

166
Q

tarsers

A

dry nosed, lack tooth comb, 2133.1133
elongate tarsals (good jumpers)
phylogenic relationships ambiguous

167
Q

platyrhines

A

new worl monkeys
small body size
three pre molar teeth
arboreal, prehensile tail in a few species

168
Q

catarhines

A

old world monkeys
ischial callosites
estrus (in some )
bilophodont molars

169
Q

new world v old world

A

lateral/flat nostrils v. nostrils point forward

170
Q

Hominoids

A

increased encephalization
brachiation
extended ontogeny
increased social complexity

171
Q

a guide to NHP

A

apes = gibbons (14 sp. indonesia and asia), orangutans(indonesia), gorillas (2 sp. africa), chimpanzees (2 sp. africa. bonobo (female dom + sexual) and chimps (male dom)), humans (1 sp. world wide)

172
Q

diet

A

most herbivores

173
Q

folivore

A

langurs and gorillas (leaf eating)

174
Q

frugivores (+ nectar feeders)

A

marmosets and tamarins (fruit eater)

175
Q

gramnivores

A

seed eaters (some baboons, orangutans, and hominids)

176
Q

omnivores

A

galagos, bush babies, lorises, pottos, chimps

177
Q

dietary and digestive strategy

A

strategic foraging

178
Q

primate communities

A

like communities of other animals , are integral parts of the tropical rainforest ecosystems (Seed dispersal)