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Exam 3 Study Guide/List of Topics (Chapters 15-21)
Chapter 15: Natural Selection
People:
Herbert Spenser
(1820-1903)
British
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Founders of the
Modern Synthesis
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Johann Friedrich
Theodor “Fritz”
Müller
(1821-1897)
German
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Henry Walter
Bates
(1825-1892)
English

Principles of Biology (1864)- coined the
phrase “survival of the fittest”
Most respected, influential and popular
philosopher of his day and a partial
advocate for Darwinism
Take on evolution was more
Lamarckian and Orthogenetic
believed evolution had a higher
purpose and a final equilibrium,
related to the social development of
humanity, to the “perfect man in the
perfect society”
Verne Grant (1917-2007)- botanist
G. Ledyard Stebbins, Jr. (1906-2000)botanist and geneticist
Ernst Mayr (1905-2005) Ornithologist
& Taxonomist
G.G. Simpson (1902-1984)- Vertebrate
Paleontologist
Bernhard Rensch (1900-1990)Ornithologist and ethologist
Edwin Brisco “Henry” Ford (19011988)- invented ecological genetics
Sergei Sergeevich Chetverikov (18801958)- geneticist whose work (1920s)
influenced Haldane, Dobzhansky and
others
Studied aposematic colors in bees,
mimicry in bees and butterflies,
termite biology, orchid fertilization,
climbing plants, and general tropical
biology
Für Darwin (Facts and Arguments for
Darwin) (1864)
Trained as a doctor in Germany but
immigrated to Brazil in 1852 where he
became a naturalist and scientist
spent 14 years in the Amazon basin
collecting and studying
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Sergei Sergeevich
Chetverikov
(1880-1958)
Russian
Julian Huxley
(1887-1975)
British
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Sewall Wright
(1889-1988)
American
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Sir Ronald A.
Fisher
(1890-1962)
English
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J.B.S. Haldane
(1892-1964)
British
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Robert Mertens
(1894-1975)
German
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discovered defensive mimicry among
rainforest butterflies
The Naturalist on the River Amazons
(1863)
geneticist whose work (1920s)
influenced Haldane, Dobzhansky and
others who founded the Modern
Synthesis
Thomas Henry Huxley’s grandson
Coined the terms: clade, grade, cline,
ethnic group, ritualized behaviors
evolutionary biologist, science
popularize, ornithologist, ethologist,
humanist, conservationist, advocate for
eugenics
Developed the mathematical
framework for understanding the
genetic consequences of migration,
effective population size, population
subdivision
Conceived of the concept of adaptive
landscapes
Evolution and the Genetics of
Populations: Genetics and Biometric
Foundations (1968-1978)
World class statistician and a founder of
population genetics
The Genetical Theory of Natural Selection
(1930)
United Mendelian population genetics with
the inheritance of continuous traits
Advocated for eugenics
a founder of population genetics
developed the mathematical theory of
allele frequency change under
selection
The Causes of Evolution (1932)
First biologist to qnaitify reproductive
fitness
Herpetologist that described:
An unusual cases where a deadly prey
species mimics a less dangerous
species
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Theodosius
Dobzhansky
(1900-1975)
American
(Ukrainian
born)
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Bernhard Rensch
(1900-1990)
German
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Edwin Brisco
“Henry” Ford
(1901-1988)
British
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G. Ledyard
Stebbins, Jr.
(1906-2000)
American
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If there is some other species that is
harmful but not deadly as well as
aposematic, the predator may learn to
recognize its particular warning colors
and avoid such animals
a deadly species will then profit by
mimicking the less dangerous
aposematic organism, if this results in
fewer attacks than camouflage would
who was one of the founders of the
Modern Synthesis
Genetics and the Origin of Species
(1937)
Defined evolution as “a change in the
frequency of an allele within a gene
pool”
Origins of the Modern Synthesis
Ornithologist and ethologist who was
one of the founders of the Modern
Synthesis
Wrote Evolution above the Species Level
(1947) which discussed how the
evolutionary mechanisms that drove
speciation could also explain the
differences between higher taxa
proposed what is now called Rensch's
rule in 1950. It is an allometric law
about the relationship between sexual
size dimorphism (SSD) and which sex is
larger. It observes that across species
size dimorphism increases with
increasing body size when the male is
the larger sex, and decreases with
increasing average body size when the
female is the larger sex
zoologist and geneticist who was one
of the founders of the Modern Synthesis
invented ecological genetics
was the first to describe and define
genetic polymorphism
botanist and geneticist who was one of
the founders of the Modern Synthesis
wrote Variation and Evolution in Plants
(1950), which combined genetics and

V.C. WynneEdwards
(1906-1997)
English
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James F. Crow
(1916-2012)
American
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Verne Grant
(1917-2007)
American
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John Maynard
Smith
Motoo Kimura
(1920-2004)
(1924-1994)
British
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Japanese
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Darwin's theory of natural selection to
describe plant speciation
proposed that a high degree of genetic
variability was necessary for major
evolutionary advances, that because of
slow mutation rates, genetic
recombination was the most likely
source of this variation, and that
variation could be maximized though
hybridization
proposed that social behaviors act to
keep social species from exceeding the
carrying capacity of their
environments; that social behaviors
evolve to limit reproduction or
fecundity
proposed this hypothesis in his book
Animal Dispersion in Relation to Social
Behavior (1962) and continued in
Evolution Through Group Selection
(1986)
Contributed to the development of the
neutral theory
Botanist who was one of the founders
of the Modern Synthesis
wrote The Origins of Adaptations
(1963) which theorized about genetic
drift, modes of speciation, natural
selection and population genetics
one of the premiere evolutionary
theorists of the 20th century, as well as
one of the most mathematically
inclined, was one of the first to
investigate the details of the costbenefit analysis for sexual versus
asexual reproduction
Coined the term “kin selection”
Geneticist; advocated for the Neutral
Theory
(1983) The neural theory of molecular
evolution
By extrapolating backward from
comparative amino acid secuqnces to
the common ancestor of the two, using
fossil evidence, Kimura estimated that
Edward O. Wilson
(1929present)
American
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W.D. Hamilton
(1936-2000)
British
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Stephen Jay Gould
(1941-2002)
American
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Richard Dawkins
Niles Eldredge
Key Concepts:
(1941present)
(1943present)
English
American
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a new neutral mutation must have been
formed and achieved fixation every 2
years on average
(1975) The New Synthesis launched a
new field of science which offered a
way to solve the contradictions by
placing humans within the tree of life
E. O. Wilson, Sociobiology: The New
Synthesis, 1975, launched a new field of
science which offered a way to solve
the contradictions by placing humans,
as Darwin had, within the tree of life
Animal behavior is shaped by natural
selection
Human behavior is determined in part
by natural and sexual selection, but
also by cultural forces which have no
equivalent in animal societies
Start with the constraints from the
genotype and then see how
environment can shape development
from that foundation
another of the world class evolutionary
biologists of the post-WW II generation
advocated for the importance of the
gene as a unit of selection
inclusive fitness theory
investigated sex ratios and cost-benefit
analyses, for the evolution of secual
reproduction
proponent of the Red Queen
Hypothesis
Paleontologist, evolutionary biologist,
science historian
Contributed to evolutionary biology
with the theory of punctuated
equilibrium 1972
Ethologist and evolutionary biologist
The Selfish Gene (1976)
Biologist and paleontologist
Contributed to evolutionary biology
with the theory of punctuated
equilibrium 1972
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Darwinian Fitness
o Measurable mathematically; is a relative not an absolute measure
o The ability of an individual to survive and reproduce in its present
environment
Natural selection
o Not goal oriented
o Does not anticipate environmental changes
o Increases reproductive success in the current environment
o Always a generation behind any changes in the environment
o modifes designs, that is development, anatomy, physiology, ecology,
and behavior in a random way
Types of Natural Selection
o Normal distribution
 Bell shaped curve
 Can be controlled by multiple genes controlling polygenic
phenotypic traits
o 1- Stabilizing selection
 The extremes are selected against producing over subsequent
generations a population with less variation, reflected in the
tighter bell-shaped curve
 examples: cliff swallows, selection for symmetry, form in
animal species
o 2 - Disruptive selection
 Individuals with intermediate features are selected against,
eventually producing over the subsequent generations a
divided result with two distinct phenotypes at the extremes
with their own bell-shaped distributions
 Examples: grove snails
o 3 – Directional selection
 Selection acts against one extreme and favors the other
 Example: peppered moths and pollution; artificial selection
pressures; finches and drought
Hardy Weinberg Principle
o (p+q)2 = p2 + 2pq + q2 = 1
 p2 = individuals homozygous for first allele
 2pq = individuals heterozygous for the alleles
 q2 = individuals homozygous for second allele
o Conditions:
o Selection coefficients
 sp2(p2)+ s2pq(2pq) + sq2(q2)= 1
 where S varies from 1.0 to 0.0
Mating systems
o Promiscuous
There are no set breeding pairs, males and females mate with
multiple partners
o Monogamous
 One female and one male organism will mate for life
o Polygynous
 One male may mate with several females
Group Selesction
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Cost-Benefit Analysis for Sexual versus Asexual reproduction:
Sexual Reproduction Asexual Reproduction
Advantages
 High Genetic
 lower energy
Variability
cost
 Facilitates
 courtship is
adaptation
irrelevant
 “speeds” up
 greatest
evolution
increase in
fitness for each
individual
Disadvantages
 higher energy
 Low genetic
cost
variability
 courtship
 Adaptation to
consumes
the
time and
environment is
resources
difficult
 usually
 “slows”
sacrifices the
evolution
fitness of one
sex to the
other

Kin selection: individuals will behave more altruistically and less
competitively toward their relatives because they share a relatively high
proportion of their genes; by helping a relative reproduce an individual
passes its genes to the next generation
Vocabulary:
1. Fitness: the level to which an organism is able to survive and reproduce
successfully given their particular set of environmental conditions
2. Fundamental niche: the total range of environmental conditions that are
suitable for existence
3. Realized niche: the part of the fundamental niche occupies by a species in
relation to the influences of interspecific competition or predation/herbivory
4. Modern Synthesis: the classic Darwinian principles combined with the
information provided by technological advances in genetics and other
biological sciences
5. Population: a group of individuals belonging to the same species that live in
the same region at the same time
6. Quantitative Characters: an inherited character that is expressed
phenotypically in all degrees of variation between one often indefinite
extreme and another; a character determined by polygenes
7. Allele frequencies: a measure of the relative occurance of an allele on a
genetic locus in a population
8. Effective population size: the number of individuals in a population who
contribute offspring to the next generation
9. Adaptive landscapes:
10. Panmictic population: a population where all individuals are potential
reproductive partners
11. Reproductive fitness: the success of a given genotype based on its success
in a population as a phenotype to increase its proportion in subsequent
generations
12. Selection pressure: any forces acting upon the survival and reproduction of
individuals in a population
13. Cryptic female choice: the ability of some female organisms to eliminate
sperm/pollen from some male donors physiologically after
insemination/pollination
14. Sperm competition: the displacement of sperm from previous mates by
males of some species
15. Sexual dimorphism: distinct differences in morphology between the sexes
of a species in addition to the difference between sexual organs
16. Sexual selection: Coined by Darwin, a type of selection arising through the
preference by one sex for certain characteristics in individuals of the other
sex; a special case of intraspecific competition or the evolutionary result of
the struggle between the individuals of one sex for reproductive access to
individuals of the other sex; in males it is expressed in competition for social
dominance or for particular resources, or by physical combat; or in females
by behaviors that control mate choice; sexual selection produces phenotypic
traits with potential costs to survival that are outweighed by reproductive
fitness gains
17. Secondary sexual characteristics: those characteristics that develop just
before an organism’s adult phase that may distinguish the sexes of a species
18. Sexual Dimorphism: when males and females differ in phenotype due to
the action of sexual selection on that phenotype
19. Mimicry: the resemblance of one organism to another or to an object in its
surroundings for concealment and protection from predators
20. Mimicry System: The close external resemblance of an organism, the mimic,
to some different organism (or inanimate object), the model, such that the
mimic benefits from the mistaken identity, by seeming to be unpalatable or
harmful or camouflaged and not detected
21. Batesian Mimicry: one or more harmless species of low population density
evolve to mimic one or more potentially harmful and plentiful species exhibit
aposematic (warning) colors/phenotypic traits
22. Müllerian Mimicry: mimicry in which all the species are unpleasant or toxic
organisms, and thus all the species in the system are harmful “models”
mimicking each other, and therefore the aposematic coloration/phenotype is
learned by predators as a deterrent regardless of which species it encounters
first
23. Mertensian Mimicry: deadly prey species mimics a less dangerous species’
aposematic phenotype so that the predator can survive to learn to avoid the
aposematic phenotype, benefitting both the mildly harmful and the deadly
species
24. Aggressive mimicry: When a predator uses any form of camouflage so that
it cannot be detected by its prey species, and, therefore, the prey individuals
come close to the predator, unaware that it is there, and then the predator
can strike and take the prey
25. Phenotypic plasticity: variation in the phenotype expressed in response to
environmental changes with no difference in underlying genotype and
indicative of underlying genotypic plasticity
26. Neutral Theory: at the molecular level most evolutionary changes and most
of the variation within and between a species is not caused by natural
selection but by genetic drift of mutant alleles that are neutral in fitness
Chapter 16: Species and Similarity: On Being the Same Yet Different.
People:
Karl von Baer
(1792-1876)
Estonian
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Richard Owen
(1804-1892)
English
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Thomas Henry
Huxley
(1825-1895)
English
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Edward Bagnall
Poulton
(1856-1943)
British
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George Gaylord
Simpson
(1902-1984)
American
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naturalist, biologist, geologist,
meteorologist, geographer, and a
founding father of embryology
Coined the term homology and analogy
and Dinosauria
regarded organs as the same
(homologs), though they served
different functions
Darwin’s bulldog
Thomas Henry Huxley was the
anatomist who led the revolution in
comparative anatomy in the Victorian
era
He devoted an entire book to the
crayfish (1879)!
Evolutionary biologis who was a life
long advocate of natural selection
Ernst Mayr gave credit to Poulton as an
early originator of the Biological
Species concept
Evolutionary species concept: “An
evolutionary species is a lineage (an
Ernst Mayr
(1904-2005)
German
Born
American
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William Hennig
(1913-1976)
German
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Leigh Van Valen
(1933-2010)
American
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ancestor-descendant sequence of
populations) evolving separately from
others and with its own unitary
evolutionary role and tendencies”
Proposed the Biological Species
Concept in 1942
His last version, from 2001 states:
"Species are groups of interbreeding
natural populations that are
reproductively isolated from other
such groups."
Completely rejected sympatry
Phylogenetic (cladistics) species: A
group of organisms that shares an
ancestor; a lineage that maintains its
integrity with respect to other lineages
through both time and space
Evolutionary biologist
proposed "Law of Extinction" drew
upon the apparent constant probability
(as opposed to rate) of extinction in
families of related organisms, based on
data compiled from existing literature
on the duration of tens of thousands of
genera throughout the fossil record.
proposed the Red Queen Hypothesis
(1973)
Key concepts:
 Comparative Embryology and Baer’s Laws
o General characteristics of the group to which an embryo belongs
develop before special characteristics
o General structural relations are likewise formed before the most
specific appear
o The form of any given embryo does not converge upon other definite
forms but, on the contrary, separates itself from them
o Fundamentally, the embryo of a higher animal form never resembles
the adult of another animal form, such as one less evolved, but only
resembles its embryo
o Early embryonic stages of related species bear more common features
than do later, more specialized developmental stages
 Defining Species (see vocabulary for detailed definitions)
o Biological species
o Ecological species
o Ring species
o Genetic species
o Agamospecies
o Chronospecies
o Evolutionary species
o Phylogenetic (cladistics) species
 Homologies help with drawing connections in evolutionary relatedness
o The Eukaryotic Cell
 Nucleus
 mitosis
 meiosis
 DNA supercoiling with histones and higher levels
 Cytoplasm
 all cellular organelles
 most central cellular biochemical pathways
 Plasma membrane
 phospholipid bilayer
 cholesterol present
o The genetic code
 One of the most powerful evidences for common ancestors
Vocabulary:
1. Neontology: branch of zoology dealing with living forms as distinct from
fossils
2. Embryo: an unborn or unhatched offspring in the process of development
3. Biological Species Concept: Species are groups of interbreeding natural
populations that are reproductively isolated from other such groups
4. Fossil species: see chronospecies
5. Vacariant distributions: geographical range of an individual taxon, or a
whole biota, is split into discontinuous parts by the formation of a physical or
biotic barrier to gene flow or dispersal
6. Genetic species: A set of organisms exhibiting similarity of DNA
7. Agamospecies: species in which sexual reproduction does not occur,
represented typically as a collection of clones
8. Ecological species: Populations that are adapted to certain ecological niches,
and because of their adaptations, will form discrete morphological clusters
9. Ring species: species with a geographic distribution that forms a ring and
overlaps at the ends
10. Chronospecies: a species which changes in morphology, genetics, and/or
ecology over time on an evolutionary scale such that the originating species
and the species it becomes could not be classified as the same species had
they existed at the same point in time
11. Evolutionary species: a lineage (an ancestor-descendant sequence of
populations) evolving separately from others and with its own unitary
evolutionary role and tendencies
12. Phylogenetic (cladistics) species: A group of organisms that shares an
ancestor; a lineage that maintains its integrity with respect to other lineages
through both time and space
13. Homology: Any similarity between phenotypic characters that is due to their
shared ancestry. Homologous structures may retain the function they served
in the common ancestor or they may evolve to fulfill different functions
14. Analogy: Any phenotypic characters that perform the same or similar
function by a similar mechanism but evolved separately
15. Parallelism: the independent development of a descendant character trait
that is not present on a common ancestor; when two taxa develop the same
character after evolutionary divergence
16. Convergence: the evolution of similar traits in response to similar adaptive
pressures, but not built upon similar genes or developmental processes
17. Developmental Homology: A related concept meaning that structures arose
from the same tissue in embryonic development
18. Homoplasy: when the organs of two different species have similar
characteristics, functions and features as a result of similarity of environment
rather than common heredity
19. Reversal: instances of homoplasy in which a character appears,
subsequently disappears, and later reappears among the descendants in one
lineage
20. Ecological equivalents: Unrelated organisms that occupy similar
habitats/niches and may or may not resemble each other due to convergence
21. Parallel evolution: the independent origin of similar features in more
closely related organisms
Chapter 17: Origin of Species
People:
Sir Edward
Bagnall Poulton
Sir Julian Huxley
(1856-1943)
British

(1887-1975)
British
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Michael J.D. White
(1910-1983)
Australian

John Maynard
Smith
1920-2004
English

entomologist that invented the term
sympatric speciation
introduced the meaning of “cline” : in
reference to population biology, is a
gradual change of phenotype (trait,
character or feature) and underlying
gene pool allele frequencies in a
species over a geographical area, often
as a result of environmental
heterogeneity
biologist wrote one of the first books to
document evidence for sympatric
speciation: Modes of Speciation (1978)
first put forth the sympatric speciation
model in 1966

suggested that homozygotes (AA and
aa) might, under particular
environmental conditions, have a
greater fitness than heterozygotes (Aa)
for a certain trait
Key Concepts:
 Speciation
o Allopatric: a physical barrier divides a continuous population
 Mechanisms that prevent interbreeding may be:
 ecological:
o seasonal breeding, migration, etc.
o habitat preference
o differing abiotic factors, etc.
 behavioral
o activity times
o food acquisition, etc.
 physiological
o reproductive biology
o fertilization
o embryonic development
o Peripatric: a small founding population enters a new or isolated
niche; when a population is divided because of the budding off of a
small completely isolated founder colony from a larger population so
that gene flow is minimal
o Parapatric: a new niche found adjacent to the original niche; when a
population at the periphery of a species adapts to a different
environment but remains contiguous with its parent so that gene flow
is possible between them; ex. Ring species
o Sympatric: speciation occurs without physical separation inside a
continuous population
o Process:
 In the beginning, there is a single population with a common
shared gene pool
 A discontinuity develops among some demes
 Changes in allele frequencies develop at various loci in the
gene pools (and, usually, changes in phenotypes) of the demes
 Separate evolution of demes continues until one or more have
diverged to the point that each deme now meets one of the
definitions of a species concept
 Species can change without speciation being initiated
 Gene flow promotes continuance and stability
 Reproductive Isolating Mechanisms
o Prezygotic mechanisms: Factors which prevent individuals from
mating
geographic, ecological, behavioral, and temporal isolation
Gametic incompatibility: Sperm transfer takes place, but the
egg is not fertilized
 mechanical mating mechanisms
o Postzygotic mechanisms: Genomic incompatibility, hybrid inviability
or sterility
 Zygotic mortality: The egg is fertilized, but the zygote does
not develop
 Hybrid inviability: Hybrid embryo forms, but is not viable
 Hybrid sterility: Hybrid is viable, but the resulting adult is
sterile
 Hybrid breakdown: First generation (F1) hybrids are viable
and fertile, but further hybrid generations (F2 and backcrosses)
are inviable or sterile


Vocabulary:
1. Adaptive radiation: the rapid evolution of one or a few forms into many
different species occupying a variety of habitats within a new geographical
area
2. Morphological/Typological species: a set of organisms sharing structural
similarities between members and discontinuities in structure between
different species
3. Anagenesis: speciation produced by directional selection
4. Cladogenesis: speciation produced by disruptive selection
5. Vicariance Distributions: distributional maps formed when an ancestral
species population is divided because of a natural physical barrier or because
intervening geographical populations become extinct
6. Introgression: postzygotic mechanisms that may be less advantageous from
that perspective, but, on the other hand, may allow some alleles to pass from
one species to the other, a form of horizontal gene transfer
7. Biotic cline: in reference to population biology, is a gradual change of
phenotype (trait, character or feature) and underlying gene pool allele
frequencies in a species over a geographical area, often as a result of
environmental heterogeneity
Chapter 18: Mass Extinctions, Opportunities, and Adaptive Radiations
People:
Baron Georges
Cuvier
(1769-1832)
French

credited with
establishing
the reality of
extinction for
the scientific
community in




George Gaylord
Simpson
(1902-1984)
American

a lecture to the
French
Institute in
1796
Proposed a
Theory of
Catastrophism
to explain
extinct
organisms
Accepted some
fossils as
evidence of
extinctions,
but did not
accept the
concept of life
evolving, in
opposition to
Buffon
Recognized
evidence of
stratification
of rock layers,
examples of
sedimentation,
uplift and
subsidence
Recognized a
Principle of
Faunal
Succession
used to assign
times to
geologic strata
in The Animal
Kingdom,
Distributed
According to
Its
Organization
(1817)
Vertebrate
paleontologist
and one of the

John Ostrom
(1928-2005)
American



Othniel Charles
Marsh
(1831 –
1899)
American


founders of
the NeoDarwinian
Modern
Synthesis
estimated (as
have many
other
evolutionary
biologists)
that 99% of all
species are
already extinct
paleontologist
who
hypothesized
that some
dinosaurs
were
endothermic
hypothesized
that feathers
evolved
primarily as a
means of
controlling
heat loss in
warm-blooded
dinosaurs
hypothesuzed
that duckbilled
dinosaurs
lived in herds
paleontologist
who discoved
some of the
first fossils of
dinosaurs,
pterosaurs,
toothed birds,
horses
presented
classic
examples of
stepwise
evolutionary
trees among
vertebrates
• (;) is
• and have
Key Concepts:
 The 6 Mass Extinctions
o Ordovician (450-440 MYA; 458 MYA)
 Second largest of the five major extinctions in terms of percent
of genera that went extinct and second largest overall loss of
life
 Second biggest extinction of marine life
 At the time all known metazoan life was confined to the seas
 More than 60% of marine invertebrates died
 The immediate cause appears to have been the tectonic
movement of Gondwana into the south polar region leading to
global cooling and falling sea levels
o Devonian (365-440 MYA; 356 MYA)
 The third largest of the five major extinction events in earths
history in terms of percentage of genera that went extinct;
primarily affected marine life
 Hard-hit groups include brachiopods, trilobites, and reefbuilding organisms; the latter almost completely disappeared,
with coral reefs only returning upon the evolution of modern
corals during the Mesozoic
 Surprisingly, jawed vertebrates seem to have been unaffected
by the loss of reefs, while agnathans were in decline long
before the end of the Devonian
 The extinction of ~20% of all animal families and 70-80% of all
animal species
 Cause is unclear; Leading theories include changes in sea level
and ocean anoxia, possibly triggered by global cooling
(glaciation on Gondwana) or oceanic volcanism
o Permian (245-251 MYA; 255 MYA)
 The Earth's most severe mass extinction event, with up to 96%
of all marine species and 70% of terrestrial vertebrate species
becoming extinct
 Some 57% of all families and 83% of all genera were killed
 Only known mass extinction of insects
 There are several proposed mechanisms for the extinctions;
The earlier phase was likely due to gradual environmental
change, while the latter phase may has been due to a
catastrophic event
o Triassic (208 MYA)
 struck marine life and terrestrial life profoundly
 At least half of the species now known to have been living at
that time went extinct
 In the oceans, a whole class (conodonts) and 20% of all marine
families disappeared
 On land, all large crurotarsans (non-dinosaurian archosaurs)
other than the crocodilians, some remaining therapsids, and
many of the last large amphibians were wiped out
 Several explanations for this event have been suggested, but all
have unanswered challenges:
 Gradual climate change or sea-level fluctuations during
the late Triassic; however, this does not explain the
suddenness of the extinctions in the marine realm
 Asteroid impact, but no impact crater has been dated to
coincide with the Triassic–Jurassic boundary; the
largest late Triassic impact crater occurred about 12
million years before the extinction event
 Massive volcanic eruptions (known from the central
Atlantic magmatic province -- an event that triggered
the opening of the Atlantic Ocean) that the would
release CO2 or sulfur dioxide and aerosols, which would
cause either intense global warming (from the former)
or cooling (from the latter)
o Cretaceous (65.5 MYA)
 Widely known as the K–T extinction event, it is associated
with a geological signature known as the K–T boundary,
usually a thin band of iridium-rich sedimentation found in
various parts of the world
 The event marks the end of the Mesozoic Era and the beginning
of the Cenozoic Era
 Essentially all non-avian dinosaurs, mosasaurs, plesiosaurs,
pterosaurs and many species of plants and invertebrates
became extinct
 Scientists theorize that the K–T extinctions were caused by one
or more catastrophic events, such as massive asteroid impacts
 Like the Chicxulub impact crater, a 10km diameter meteorite
leaving a crater ~200 Km in diameter
 or increased volcanic activity

o Human-Caused Holocene (Anthropocene) Mass extinction (10,000
years ago-present)
 Caused by humans:
 Excessive Predation (food, fur, collecting, exotic pets,
pest eradication, Chinese medicine, etc.)


 Destruction of keystone species
 Introduction of Exotic Species
 Competitors, Predators
 Diseases
 Exotic Pet Trade
 Air and Water pollution
 Soil and Ocean Pollution
Abiotic causes for Mass Extinctions:
o Plate Tectonics
 Intermingling of Biotas / Introduced species effects
 Trophic Stability
 When a landmass is broken in two, this adds area along
the perimeter where they split; this adds to the
intertidal area which is a species and nutrient rich
habitat
 When two landmasses are brought together, this results
in loss of available intertidal area
 Changes in Sea Level and ocean chemistry
 Volcanic Activity changing atmospheric gases and dust levels
 Ice Ages with glaciations, falling sea levels, increased tropical
aridity
o Planetary Collisions
o Cosmic Forces & Periodic Galactic Cycles
Evolution of Flight:
o Flight has evolved 4 separate times in animals (1 in invertebrates; 3 in
vertebrate tetrapods):
 Insects (Paleopterans and Neopterans have different designs)
 Flying Reptiles (non-dinosaur pterosaurs and pteranodons)
 Birds (descendants of dinosaurs)
 Bats (Megachiropterans & Microchiropterans)
o Insect flight:
 Paranotal hypothesis: suggests that the insect's wings
developed from paranotal lobes on the body
 Epicoxal hypothesis: suggests that the wings developed from
movable abdominal/ tracheal gills found in many aquatic
insects; these tracheal gills started as extensions of the
respiratory system and over time were modified into
locomotive purposes, eventually developed into wings
 Endite-Exite hypothesis: suggests that the wings developed
from the adaptation of endites and exites, appendages on the
respective inner and outer aspects of the primitive arthropod
limb; the innervation, articulation and musculature required
for the evolution of wings are already present in podomeres
Paranota plus leg gene recruitment hypothesis: hypothesis
suggests that the wings developed from mostly immobile
winglike projections from the back of the thorax
 Flight patterns:
 Direct: wing muscles insert directly at the wing bases,
which are hinged so that a small movement of the wing
base downward, lifts the wing itself upward like rowing
through the air; movement is directed by movement of
the wings in Neopterans
 Indirect: The wing muscles of Paleopterans insert
directly at the wing bases, which are hinged so that a
small movement of the wing base downward, lifts the
wing itself upward; movement is directed by movement
of the thorax
 Evolutionary reversals
o When organisms adopt a previously occurring form or function that
appeared in an ancestor
Vocabulary:
1. Mosaic Evolution: evolution in which individual sections of an animal can
arise independently of one another
2. Endothermy
3. Co-evolution

Chapter 19: Human Origins and Evolution
People:
Marie Eugène
1858-1940
Dutch
François Thomas
Dubois

Physician, paleontologist and geologist
who discovered “Java man,”
(Pithecanthropus) Homo erectus
Robert Broom

Physician and paleontologist who first
studied mammal-like reptiles
Supported Dart’s hypothesis that
“Taung child,” Australopithecus
africanus was in the human lineage
Discovered (Paranthropus) A. robustus
specimens
physical anthropologist that identified
and names the first Australopithecus
africanus specimen a.k.a. the Taung
child skull
originated the “killer ape” theory
surgeon, anatomist, primatologist,
paleontologist who contributed to the
unraveling of the Piltdown Man hoax
1866-1951
South
African


Raymond Dart
Sir Wilfrid
Edward Le Gros
Clark
1893-1988
(1895 –1971)
Australian

British


Louis Leakey
1903-1972
British
Kenyan






Mary Leakey
1913-1996
British
Dian Fossey
1932-1985
American







Mary Leaky’s husband
spent their lifetimes working on human
origins in and around Olduvai Gorge
The Leakeys are the first family of
human prehistory whose research
convinced the world of the African
origin of humans
Discovered Zinjanthropus
(Australopithecus) boisei, “nutcracker
man,” Homo habilis, “handyman,” the
Laetoli fossil Australopithecine
footprints, among many other fossils
and artifacts
Louis was also the main stimulus for
field studies of the great apes, giving a
start to Jane Goodall, Dian Fossey, and
Biruté Galdikas
They established or supported several
major museums, research centers and
the Leakey Foundation
see above description
Louis Leaky’s wife
Primatologist given her opportunity to
study mountain gorillas by Louis
Leakey
Fossey conducted and sponsored
research on gorillas, first in the
Democratic Republic of Congo (1966)
and later (1967) at the Karisoke
Research Station in the Virunga
Mountains, Rwanda, until her tragic
murder
autobiography, Gorillas in the Mist,
became the basis for a movie
conducted and sponsored research on
chimpanzees at the Gombe Stream
National Park, Tanzania, since 1960
Identified tool use and tool making,
cooperative hunting, murder and
warfare in chimpanzees, the latter two
behaviors possibly induced by feeding
the animals to make observations more
easily

Jane Goodall
1934-
British

Donald Johanson
1943-present
American

Richard Leakey
1944-
British


Biruté Galdikas
1946-
German


Frans de Waal
1948-
Dutch

Tim White
1950-present
American

Author of more than a dozen scientific
books and a similar number of
childrens’ books
primate ethologist given her
opportunity to study chimpanzees by
Louis Leakey
(1974) discovered “Lucy”
(Australopithecus afarensis) 1974 at
Hadar in Afar triangle region of
Ethiopia
Kenyan physical anthropologist,
second son of Louis and Mary Leakey
Discovered many example specimens
of early hominids and hominins,
including the new species
Australopithecus aethiopicus in 1992
Primatologist given her opportunity to
study orangutans by Louis Leakey
conducted and sponsored research on
orangutans atTanjung Putting Reserve
in Indonesian Borneo from 1971 to the
present
primatologist who studied social
behavior in monkeys, chimpanzees and
later bonobos and draws connections
to human social behaviors
(1993) discovered Ardipithecus
ramidus
Key Concepts:
 Primates
o Primates arose 85 Mya during the last third of the Cretaceous Period
from a lineage of small, insect-eating, tree-dwelling shrew-like
mammals
o Plesiadapiformes – the Ancient “Stem Primates” or Precursors:
Strepsirhines (“wet-nosed primates”)
 have a moist nose pad (rhinarium)
 are small-bodied nocturnal omnivores
 the lemurs of Madagascar and the lorises of Africa and South
East Asia
o Haplorhines (“dry-nosed primates”)
 have no rhinarium but a dry continuous upper lip
 are larger-bodied, diurnal omnivores with shorter faces than
strepsirhines, forward-directed eyes and larger brains
 monkeys, apes and humans
o Evolutionary Trends:
 K-selected life strategy
 generalized (ancestral) mammalian body plan
 arboreal omnivore ecology and diurnal activity
 large, complex brain (for learned behaviors)
 binocular (stereoscopic) color vision
 reduced emphasis on olfaction correlated with a more
flattened face and shorter snouts and jaws with generalized
dentition
 mobile limbs with grasping hands and feet (some opposability
of thumbs and great toes)
 excellent hand-eye coordination for locomotion
 flattened nails instead of claws and sensitive pads on the
undersides of fingers and toes
 complex social organization
 permanent association of adult males with the group (most
tend to associate at least with offspring), male association
uncommon in non-primate mammals
 sexual selection and sexual dimorphism
 flexible mating systems
 litter size of one with prolonged child care
 altricial juveniles play, observe and imitate adults, explore
their environment
 delayed maturity and long life span
 recognition of individuals within groups by anatomical and
behavioral differences
 complex vocal communication with gestures and facial
expressions
o Three morphological grades: prosimians, monkey, and apes
 Prosimians
 Prosimians probably most resemble the early arboreal
ancestral primates, as do the primates’ cousin, the tree
shrew
 Prosimians include the lemurs of Madagascar and the
lorises, pottos, and tarsiers of tropical Africa and
southern Asia
 more reliance on olfaction, with a moist, fleshy pad
(rhinarium) at the end of the nose and a long snout
 somewhat more laterally placed eyes
 forward-projecting lower incisors and canines form the
dental comb used in grooming and feeding
 mark territories with scent (other primates do not)
 differences in reproductive physiology, shorter
gestation and maturation (less K-selected)
 Anthropoids (monkeys and apes)






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

generally larger body size
larger brain (in absolute terms as well as relative to
body weight)
more rounded skull
complete rotation of eyes to front of face with full
binocular vision
bony plate at the back of eye socket , a bony orbit
haplorhine: no rhinarium (less reliance on smell)
increased parental care
increased gestation and maturation periods
more mutual grooming
o Monkeys
 Old and New World monkeys arose 35 to 40 Mya in what is
now Africa
 New World (Platyrhines)
 New World monkeys have broad, widely flaring noses
with lateral-facing nostrils — called platyrrhine (flatnosed)
 Almost exclusively arboreal and diurnal (one nocturnal
species), some species never coming to the ground
 A wide range of sizes, diets and ecological adaptations
 All live in moist tropical forests of southern Mexico into
Central and South America
 Two families: Callitrichidae and Cebidae
 Old World (Catarhines)
 Much more varied in morphology and behavior than the
New World monkeys
 They have downward facing nostrils and are called
catarrhine
 Most are quadrupedal and primarily arboreal, but some
(like baboons) are well adapted to the ground
 Most hold their upper bodies erect for long periods of
time while feeding, sleeping, and grooming ― associated
with their prolonged sitting are hard callouses of naked
skin on the buttocks called ischial callosities, which
serve as sitting pads
 Most have a great deal of manual dexterity
 Most have tails (non-prehensile) that are used for both
balance and communication
 Pronounced sexual dimorphism
o Hominids
 Traits:
 generally larger body size, except the gibbons and
siamangs



absence of a tail
shortened trunk (lumbar area relatively shorter and
more stable)
 differences in position and musculature of shoulder
joint (adapted for suspensory locomotion ―
brachiation)
 more complex brain and cognitive abilities
 more complex behaviors and social behaviors
 lengthened period of infant development and
dependency
 Gibbons and Siamangs
 Orangutans
 Gorillas
 Chimpanzees
 Bonobos
o Earliest Haplorhine primate: Archicebus achilles, a 55 million-year-old
tree-dwelling haplorhine that lived in what is now central China
o Darwinus masillae (~47 mya), described in 2009, is believed to be
ancestral to African hominoids and, therefore, to hominins
o Gigantopithecus: the largest primate to ever walk the earth
The evolution of humans
o Sahelanthropus tchadensis (5-6 MYA)
 The specimen, named Toumaï (“hope of life” in the local
language) is a young boy ape
o Orrorin tugenensis
 The next oldest, dates between 5 & 6 mya in Kenya (Tugen
Hills)
 The size of a chimpanzee
o Ardipithecus ramidus (5.6 – 4.3 mya)
 Poorly known from Ethiopia.
 Only fragments, but some are mandibles with teeth
 had a small brain, measuring between 300 and 350 cm3
 displayed characteristics of modern human skeletons and
chimpanzees  the “missing link”
o Ardipithecines
 A. kadabba, dated to approximately 5.6 million years ago (late
Miocene)
 A. ramidus, which lived about 4.4 million years ago during the
early Pliocene
o Piltdown Man Hoax (1912-1953)
 The Piltdown hoax is perhaps the most famous archaeological
hoax in history. The forgery consisted of the stained and
modified lower jawbone of an orangutan combined with the
skull of a fully developed, modern man and placed in fossil
beds in Sussex, England. Big brains evolved first!
Contemporary dating suggested this “missing link” lived
200,000 to 1,000,000 years ago. That error retarded the
understanding of human evolution for 40 years!
o Australopithecines: the first hominins
 Australopithecus anamnesis
 Australopithecus anamensis was first described by Mary
Leaky in 1995 from 3.9 to 4.4 mya deposits in northern
Kenya
 Australopithecus afarensis (3.5 MYA)
 “Lucy” was discovered by Donald Johanson and Tom
Gray in 1974 at Hadar in Afar triangle region of Ethiopia
 “Lucy’s” age is about 3.2 mya
 an adult brain volume of ~380-500 cc (intermediate
between chimp and gorilla values)
 small muscular body of ~60 lbs.
 height of 3.6 – 4 feet with arms relatively longer than in
modern humans
 Fingers and toes have more curvature
 adaptations in “Lucy’s” hip, leg and foot allow a fully
bipedal means of locomotion
 footprints found, indication of parental care and bipedal
walking for long distances
 Gracile
 Australopithecus bahrelghazali
 The only Australopithecine found in North-Central
Africa, in Chad (1993)
 Slightly more vertical chin than other
Australopithecines
 Radiometrically dated to 3.0 - 3.6 mybp
 Australopithecus africanus
 South Africa was the home to the species
Australopithecus africanus, which lived 3.0 to 2.0 million
years ago
 This species was the first of the a
 Australopithecines to be described
 Raymond Dart named the genus and species after his
discovery of the famous Taung child in 1924
 Many features of the cranium of A. africanus are more
evolved than that of earlier A. afarensis
o These features include a more globular cranium
and slightly higher ratio of brain size to body size
o Also the teeth and face appear less like a
chimpanzee
 Gracile
 Australopithecus garhi


existed 2.5 million years ago
Characteristics:
o cranial capacity of 450ml.
o canines and premolars like genus Homo
o huge molars
o no canine diastemas
o prognathic face
o ape-like arms and legs
 The importance of this hominid is that it was found with
many “Oldowan” tools and an array of slaughtered
animals
 Australopithecus aethiopicus
 robust
 Australopithecus boisei
 Robust
 OH 5, "Zinjanthropus,” "Nutcracker Man"
 Paranthropus boisei
 Discovered by Mary Leakey in 1959 at Olduvai Gorge in
Tanzania
 Estimated age is 1.8 mya
 Australopithecus robustus
 Robust
 DNH 7, "Eurydice"
 Discovered by André Keyser in 1994 at the Drimolen
cave in South Africa
 DNH 8, “Orpheus" mandible
 Estimated age is between 1.5 and 2.0 Mya
 Australopithecus sediba
 Four partial skeletons discovered in 2008
 Dated between 2.0 and 1.5 mybp, best estimate ~1.98
mybp
 Cranial capacity (420-450 cc) is at the upper end of
Australopithecine values; well below early Homo (~630
cc)
 A. sediba had a surprisingly modern hand, whose
precision grip might have been capable of tool making
 The pelvis, hind limb, and feet are also intermediate
between other Australopithecines and later Homo in
terms of the continued improvement in bipedalism
o The Genus Homo
 first appears in the fossil record in East Africa around 2.4 Mya
 Early Homo are similar in size to the Australopithecines, but
with a larger brain (600 to 700 cm3) and smaller molar teeth
 Descendants of the gracile lineage
 Homo habilis (2.0-1.9 MYA)

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bigger brain: 600 – 800 cc
Skulls suggest portions of the brain associated with
speech were enlarged
 No sagittal crest
 Less prognathic face with more pronounced chin
 No canine diastemas
 Smaller zygomatic arch
 Associated with stone tools
Homo rudolfensis
Homo ergaster
Homo erectus (1.9-0.3 MYA)
 1891 - Eugene Dubois discovers H. erectus in Java
 Dubois calls it Pithecanthropus erectus initially, aka
“Java Man”
 Specimens in China were called Sinanthropus; aka
“Peking Man”
 dates from 1.9 mya to 27,000 years B.P.
 994 cc average brain size (compared to 612 cc average
for H. habilis)
 Acheulean tool industry
 Widely distributed
 Taller than previous hominins
 First hominid where data exists to suggest the
deliberate use of fire, building of shelters, caring for the
infirm of the group
Homo heidelbergensis
 Homo heidelbergensis ("Heidelberg Man") is an extinct
species of the genus Homo which may be the direct
ancestor of Homo neanderthalensis in Europe
 H. heidelbergensis stone tool technology was similar to
the Acheulean tools used by Homo erectus
 The best evidence found for these hominins date to
between 600,000 and 400,000 years ago
 Most fossils of H. heidelbergensis come from a 350,000
year old site in Northern Spain containing 28 humans,
stone tools, and remains of carnivores
Homo Sapiens
 Modern humans who entered Asia and Europe from
Africa 100,000 to 60,000 years ago
 Anatomically Modern – 35,000 years BP to present
Homo sapiens idaltu (humans)
 The term anatomically modern humans is now used for
extant and fossil individuals of the species Homo sapiens


Homo sapiens idaltu - idaltu meaning "elder" in the Afar
language
 Three individual specimens of anatomically modern
humans discovered in ~157,000 year-old deposits at
Herto, Ethiopia are the geologically oldest members of
genus Homo
 Homo sapiens neanderthalensis
 30,000 - 200,000 ya
 lived in caves and open areas
 large brains ― about 1,400 cc on average (somewhat
larger than modern H. s. sapiens average)
 heavily muscled robust torso
 short limbs and broad nasal passages(cold adaptations)
 long low skull with pronounced brow ridges
 later remains show a decrease in robustness of the front
teeth and face, suggesting the use of tools replaced teeth
as tools
 Mousterian Tools
 Evidence of burial ceremonies and musical interest and
development (flutes)
 Homo neanderthalensis coexisted with Homo sapiens for
at least 20,000 years, perhaps as long as 60,000 years
o Suggested that maybe they interbred with or
were killed/out competed by H. Sapiens
 Homo sapiens sapiens
o 35,000 years BP in western Europe to 17,000
years BP
o 1,600 cc cranial capacity
o With the appearance of Cro-Magnons, human
evolution became almost entirely cultural rather
than biological
o Prominent tool use, art, sculpture, music
 Homo floresiensis
o one meter high
o lived on Flores 12,000 yrs ago
o upright posture
o 380 cc cranial
o size (like a chimp)
o characteristics of fossil highly resemble down
syndrome
Overall timeline:
o Homo habilis (2.0 – 1.6 MYBP)
o H. rudolfensis (2.4-1.6 MYBP)
o H. erectus (1.9-27 KYBP)
o H. heidelbergensis (800-100 KYBP)
o H. neanderthalensis (300-30 KYBP)
o H. sapiens ? (Denisovans) (~40 KYBP)
o H. sapiens sapiens (130 KYBP – present



Dmanisi Hominins = Homo erectus georgicus
o 5 skulls found together
o 1.8 million year old
o Oldest individual without teeth, theorized to have been receiving care
from other members (evidence of social behaviors and family groups)
Ape vs Hominid Skeletons
o Respectively, the backbone joins the back of the skull in apes versus
the bottom
o Ape rib cage broad at the base; bipedal forms have narrower rib cage
o The ape backbone is arched while the hominin is S-shaped
o The ape pelvis is long and narrow while the hominin is bowl-shaped
o Ape femur angled out; hominin angled inward
o The arms are long in both, but shorter than hindlimbs in the ape
compared to the hominid
o The ape femur is shorter and angled out; hominid femur is longer and
angled in (knees close together)
o The ape has a grasping flat foot; the hominid has a double arched foot
with no ability to grasp
Bipedalism
o Bipedalism is not necessarily for running faster, but it is more
sustainable for walking over long distances
o Advantages:
 Improved predator avoidance
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 Improved food acquisition
 Improved thermoregulation while walking/running
 Improved reproductive success
o Adaptations:
 a change of the big toe (hallux) from grasping in apes to
striding in hominids
 repositioning of the hominid knee more under the pelvis
 shortening of the hips to a broader base of support of the
upper body
 wider hips to support weight
Evolution theories
o Multiregional Continuity Hypothesis
 Proposes the parallel origin of Homo sapiens in different
continental regions, Africa, Asia, and Europe
 This model assumes gene flow by migration among the
subpopulations from time to time, similar to what we observe
in human populations in the centuries of recorded history
o Out-of-Africa Hypothesis
 Homo sapiens evolved from Homo erectus only in Africa, and
thereafter migrated to Europe
 Proposes the origin of Homo sapiens in a single geographical
region, Africa, followed by dispersal to other continents
 This model assumes almost no gene flow by interbreeding
between the subpopulations of Homo erectus and the
expanding African lineage of Homo sapiens
 Genetic evidence supports this model
MtDNA and Human migration
o Rebecca Cann and coworkers proposed a 200,000-year-old common
mitochondrial DNA ancestor (dated modified to 140,000 ybp)
o The “Mitochondrial Eve”*
o All of the non-African mtDNA sequences are variants of the African
sequence
o Most of the variability in mtDNA sequences occurs among members of
African populations
 Supports the out of Africa hypothesis
Modern humans
o Y-Chromosome “Adam”
 A large proportion of the human Y chromosome does not
participate in recombination (makes tracing lineages easier)
o Common African ancestor living about 150,000 years ago
 Autosomal Human
o Phylogenetic analysis of 29 autosomal genes —from 26 populations
supports a single African origin of humans around 200,000 years ago
Variation in humans
o Body types, hair color/location/amount, eye color, etc
Vocabulary:
1. Hominid: a member of family hominidae, which includes all apes & all
hominins (bipedal apes)
2. Hominin: a member of subfamily homininae, which includes bipedal humans
& extinct close bipedal relatives
3. Knuckle walking: locomotion characterized by walking on all fours with the
front limbs supported by the knuckles
4. Brachiation: swinging in treetops as a form of locomotion
5. Bipedalism: characterized by walking on two feet for long distances
6. Lumpers: taxonomists who prefer to err on the side of shared characters
and an appreciation of the breadth of individual variation in traits
7. Splitters: taxonomists who prefer to err on the side of divergent characters
and see variation as indicative of separation of populations
8. Plio-Pleistocene: an archaeological term used to describe a continuous
sequence of dated sedimentary layers in Jakarta, East Africa; dates from
about 2.5 Mya to 1.5 Mya
9. Oldowan: simple stone tools from the tool-making industry in the Olduvai
Gorge, Kenya. This type of tool making occurred about 2.5 - 2 mya.
10. Acheulean: a tool industry characterized by roughly made hand axes found
at St. Acheul, France. This type of toolmaking occurred about 1.5 - 0.2 mya.
Chapter 20:
Ivan Pavlov
Karl von Frisch
1849-1936
1886-1982
Russian
Austrian





Konrad Lorenz
1903-1989
Austrian




Dog studies with classical conditioning
1973 Nobel Prize in Physiology or
Medicine
entomologist who studied insect
communication
Made major contributions to the study
of honey bees, their ability to
communicate to hive mates about food
sources with the waggle dance, use of
pheromones, and their ability to see in
color and in ultravioltet and polarized
light
Wrote Dancing Bees, A Biologists
Remembers, Animal Architecture, and
other works
1973 Nobel Prize in Physiology or
Medicine
ornithologist and ethologist
Studied instincts and fixed action
patterns in birds, and later became
interested in human behaviors
Wrote many books including King
Solomon’s Ring and On Agression

C.P. Snow
1905-1980
English


Nikolaas
Tinbergen
1907-1988
Dutch




Robert Hinde
1923-present
British


Desmond Morris
1928-present
British



Edward O. Wilson
1929-present
American

raised these greylag goslings from first
hatching, so it was to him that they
imprinted, expressing their innate
behavior of following their “parent” 
Imprinting
(1959) The Two Cultures
thesis was that the breakdown of
communication between the "two
cultures" of modern society — the
sciences and the humanities — was a
major obstacle to solving the world's
problems
1973 Nobel Prize in Physiology or
Medicine
zoologists who studied fish, birds and
insects in nature and the laboratory,
and later autism
A better experimentalist than Lorenz,
the theoretician
Wrote The Study of Instinct, The Herring
Gull’s World, Social Behavior in Animals,
Curious Naturalists, etc.
zoologist who studied birds, then
primates, and later humans
Wrote Animal Behaviour: A Synthesis of
Ethology and Comparative Psychology
(1966), a classic work that helped
integrate research in psychology and
ethology, Biological Bases of Human
Social Behaviour (1974), Individuals,
Relationships and Culture (1987),
Towards Understanding Relationships
(1979), and Why Gods Persist (1999),
etc.
ethologist, popularizer of science, and
surrealist painter.
Happy to take controversial positions
when advocating for the biological
basis of human behaviors
Wrote the bestsellers The Naked Ape
and The Human Zoo, among nearly
eighty volumes
(1975) The New Synthesis launched a
new field of science which offered a




George B. Schaller
1933-present
American





Jared Diamond
1937-present
American



David P. Barash
1946-present
American

way to solve the contradictions by
placing humans within the tree of life
E. O. Wilson, Sociobiology: The New
Synthesis, 1975, launched a new field of
science which offered a way to solve
the contradictions by placing humans,
as Darwin had, within the tree of life
Animal behavior is shaped by natural
selection
Human behavior is determined in part
by natural and sexual selection, but
also by cultural forces which have no
equivalent in animal societies
Start with the constraints from the
genotype and then see how
environment can shape development
from that foundation
Perhaps the world’s greatest living
field biologist and ethologist
Preceded Dian Fossey with his 1959
study of the mountain gorilla
Since has studied big cats, pandas,
African, Tibetan, Brazilian, Chinese and
Southeast Asian fauna
Helped establish many national parks
in Asia
Has won many awards and written
several dozen books, beginning with
The Mountain Gorilla – Ecology and
Behavior (1963), and, recently, A
Naturalist and Other Beasts: Tales
From a Life in the Field (2007)
physiologist, ornithologist,
biogeographer and evolutionary
biologist
Became interested in human cultures
and history while studying birds in
New Guinea
Books include The Third Chimpanzee;
Why Is Sex Fun: The Evolution of Human
Sexuality; Guns, Germs, and Steel: The
Fates of Human Societies; and Collapse:
How Societies Choose to Fail or Succeed.
psychologist and sociobiologist



Barash has been named one of the
country's "101 Most Dangerous
Professors," by right-wing writer David
Horowitz, because of his advocacy of
peace and other progressive causes, as
well as his avowed atheism and
persistent exploration of evolutionary
biology and its application to human
behavior
Excellent writer and author of more
than 25 books
Natural Selections: selfish altruists,
honest liars and other realities of
evolution (2007)
Key Concepts:
 Nature vs Nurture
o Innate vs learned behaviors (see vocabulary)
o Instincts (a.k.a. fixed action patterns (see vocabulary)
o Filial Imprinting: imprinting behavior of offspring in terms of
recognition of their parent(s)
o Biased learning is a restricted form of learning ― the ability to learn
and modify behavior from a restricted set of environmental stimuli
o Sexual imprinting: Male zebra finches select a mate based on the
color pattern of the female that rears them, regardless of species
o Reverse sexual imprinting (Westermarck Effect see vocabulary)
o Genetic sexual attraction: When a brother and sister are brought up
separately, never meeting, they may find each other very sexually
attractive as adults; first cousins are also often highly attracted
o In general, learned behaviors will always be:
 Nonheritable -- acquired only through observation or
experience
 Extrinsic -- absent in animals raised in isolation from others
 Permutable -- pattern or sequence may change over time
 Adaptable -- capable of modification to suit changing
conditions
 Progressive -- subject to improvement or refinement through
practice
o Most behaviors have instinctive and learned components, a spectrum
related to the size and complexity of the animal’s nervous system
o Genes vs environment
 In humans, genes provide a person with the innate ability to
speak language(s), but the culture into which the person is
born provides the particular language(s) learned





Intelligence — and our consequent ability to learn from our
own experience or from the experiences of others
Cultural transmission of learned behavior eliminates the
hazards encountered when an individual must learn by trial
and error to cope with environmental variables
Language
o Developed slowly over time
o One of the most important human synapomorphies: Language makes
long-term cumulative cultural evolution possible
o Aids in coordination, expression, communication, learning, and
memory
o Some animals are also capable of understanding and speaking basic
languages
o 3 - Properties of Language
 Symbolic: represents objects, actions, events & ideas
(ex: car = class of objects that have certain properties)
 Generative: limited number of symbols can generate infinite
array of novel messages (there is always something novel)
 Structured: infinite variety is structured in a limited number of
ways (Rules govern the arrangement of words into phrases
and sentences)
o Gossiping hypothesis
o Substitute for grooming hypothesis
o Increasing group size hypothesis
o Genetic origins
 FOXP2 gene: Language or Speech gene responsible for major
inherited speech disorder (KE family studied)
o Vocal anatomy
 Sinuses
 Chin
 Pharynx and epiglottis modifications
 Oral cavity shape and size
Human culture
o Humans have two hereditary systems:
 a genetic system, which transfers biological information from
biological parent to offspring through the coding properties of
DNA
 a cultural system, which transfers cultural information, ideas
from speaker to listener, from writer to reader, from
performer to spectator through social interactions coded in
language and custom, and embodied in records and traditions
o eugenics
 Positive Eugenics: increase the frequency of beneficial alleles
 Negative Eugenics: decrease the frequency of harmful alleles
Sociobiology
o Animal behavior is shaped by natural selection
o Human behavior is determined in part by natural and sexual selection,
but also by cultural forces which have no equivalent in animal
societies
o Start with the constraints from the genotype and then see how
environment can shape development from that foundation
Vocabulary:
1. Ethology: the scientific study of animal behavior
2. Innate behaviors: behaviors which exhibit little variation among
members of a species and appear at predictable times in development
3. Learned behaviors: behaviors which require exposure to various
environmental stimuli to develop, usually require trial-and-error
repetition to improve their efficiency and exhibit considerable
variation among members of a species
4. Fixed action patterns: Relatively complex innate, predictable,
stereotypical behaviors which are present in individuals, sometimes
even from birth, and performed completely without requiring any
experience
5. Westermarck Effect: When two people live in close domestic
proximity during the first few years in the life of either one, both are
desensitized to later close sexual attraction
6. Naturalistic fallacy: committed whenever a philosopher attempts to
prove a claim about ethics by appealing to a definition of the term
"good" in terms of one or more natural properties (such as "pleasant",
"more evolved", "desired", etc.)
7. Language: symbols that convey meaning, plus rules for combining
those symbols so that they can be combined to generate infinite
variety of messages
8. Clone: an organism descended from and genetically identical to
another organism
Chapter 21: Culture, Religion and Evolution
People:
Nicolaus
(1473-1543)
German
Copernicus
Tycho Brahe
(1546-1601)
Danish

Galileo Galilei

(1564-1642)
Itialiam


Formulated the heliocentric model of the
solar system
Nobleman and astronomer known for his
accurate and comprehensive astronomical
and planetary observations
Astronomer, physicist, engineer,
philosopher, and mathematician
Known as the father of observational
astronomy

Johannes Kepler
Isaac Newton
(1571-1630)
(1642-1727)
German

English




Carl von Linné
(Carolus
Linnaeus)
Georges-Louis
Leclerc, Comte de
Buffon
William Paley
(1707-1778)
Swedish


(1707-1788)
French

(1743-1805)
English



Sir Charles Lyell
(1797-1875)
British


Samuel
Wilberforce
(1805-1873)
British



Charles Darwin
(1809-1882)
British

Major supporter of Copernicus’ work;
telescope inventor
Mathematician, astronomer, and
astrologer
Known for his Laws of Planetary Motion
Discovered the Law of Universal
Gravitation
Proved Kepler’s three Laws of
Planetary Motion
Calculated that an Earth-sized sphere
would require 50,000 years to cool to
it’s present temperature (older than
the Bible indicated)
Botanist
Established a binomial nomenclature
system
Calculate that the Earth was 75,000
years based on the cooling rate of iron
Clergy man, Christian apologist,
philosopher, and utilitarian
Wrote Natural Theology; or, Evidences
of the Existence and Attributes of the
Deity (1802)
Major influence on young Charles
Darwin
Laywer and foremost geologist of his
time
Initially thought the age of the earth
was hundreds of thousands of years,
eventually millions of years
Anglican Bishop who attacked Darwin's
theory as incompatible with the Bible
attempted to destroy Darwin's theory
through scientific arguments
aimed final point at Huxley when he
asked whether it was through his
Grandfather or Grandmother that
Huxley claimed descent from a monkey
Naturalist who established that all
species of life have descended over
time from common ancestry, and
proposed the scientific theory that this
branching pattern of evolution resulted
Alfred Russel
Wallace
(1823-1913)
British
John Thomas
Scopes
(1900-1970)
American
from a process that he called natural
selection.
 The author of the ground breaking
book Origin of Species.
• spent 5 years in South America, 18481852; the ship he was on, Helen, burned
on homeward voyage along with all of
his work collected over the 5 years
 (1854-1862) explored the east indies
 contracted malaria in the indies
 dispersalist
• Wallace wrote letters to Darwin
outlining his independent conception
of the theory of Natural selection
(though Wallace did not use that term)
 proposed natural selection and
evolution with Darwin but took a
background role
 described natural selection as favoring
the mating barriers among populations
if hybrid inferiority occur
 Father of Biogeography and proposed
six biogeographic realms for the earth,
based primarily on animal
distributions
 The Geographical Distribution of
Animals (1876) and Island Life (1880)
• high school teacher; defendant in the
most famous confrontation between
evolution and biblical creationism;
convicted of ignoring the ban against
teaching evolution in Tennessee
schools
Key Concepts:
 Science as a way of knowing
o The Universe Is Understandable.
o The Universe Is a Vast Single System In Which the Basic Rules Are
Everywhere the Same.
o Scientific Ideas Are Subject To Change.
o Scientific Knowledge Is Durable.
o Science Cannot Provide Complete Answers to All Questions
 Be able to compare and contrast Intelligent Design and the Theory of
Evolution based off of the things you have learned thus far!
o We observe the world around us via natural laws and observations
not supernatural laws or observations
o Disproofs to the theory of evolution:
 an inversion of the evolutionary sequence such as evidence of
humans in the Paleozoic or Mesozoic Eras
 finding the same species in two separated geographical
locations when their presence was not caused by migration
between these areas
 Neither these, nor any other lines of evidence to refute
evolution have been discovered!
o The evolution of similar structures in vastly different organisms
(camera type eyes)
o No designer genes; natural selection
o Scope’s Trial in Dayton TN 1925
o religious arguments have explanatory power with respect to belief
systems, but they are not scientific explanations
o Proponents of Intelligent Design often assert that component parts of
a complex structure, where molecule, cell, or tissue, could not be
preserved by natural selection while the complex structure has not
yet come into being
 Wrong!
 Let’s look at more examples: the lens proteins of the eye and
the Eukaryotic flagellum
o Natural Selection does not produce perfect organisms
Vocabulary:
1. Methodological Naturalism: The only hypotheses researchers propose are
to account for natural phenomena, and the only explanations they accept, are
hypotheses and explanations that involve strictly natural causes
2. Ontological Naturalism: The natural world, the physical material universe,
is all there is