ANT 231 Midterm
What are the fundamental criteria for natural selection?
1. A trait must be inherited if natural selection is to act on it. 2. Natural selection cannot occur without population variation in inherited characteristics. 3. Fitness is a relative measure that changes as the environment changes. 4. Natural selection can act only on traits that affect reproduction.
What are the four mechanisms of population genetics (evolutionary mechanisms)? Think of an example of each
1. Mutation- spontaneous, induced, point, transposable elements 2. Gene Flow- Mongol Horde, Type B blood type 3. Genetic Drift- random, bottleneck, founder effect 4. Sexual Reproduction & Recombination- meiosis, mitosis
Why might the "man the hunter" theme in popular thought be considered debunked through primate studies?
1. adult apes typically get their own food 2. females spend more time foraging, making tools 3. tools associated with subsistence 4. Dominant males may actually compromise reproductive success
Approximately when and where did the earliest apes appear?
22 MYA in Africa
adducted toe
An adaptation from monkey feet (big toe used for grabbing) to human feet (big toe used for acceleration)
autogrooming
An animal grooming itself
allogrooming
Animals grooming each other
What are the four main fields of anthropology?
Cultural, linguistic, biological, archaeology
What are the concepts of cultural relativism and ethnocentrism?
Ethnocentrism is the concept of viewing other cultures from the inherently biased standpoint of one's own culture. On the contrary, cultural relativism refers to the viewing of another culture and the practices it entails from the perspective of that culture.
peppered moths (example)
Is an example of how selective pressures work. When coal factories led to the darkening of trees, the lighter colored moths which were once camouflaged, were now more noticeable, leading to the increase in dark colored moths rather than light colored ones.
What types of human variation exist that are environmentally related and not necessarily visible (think of nutrition and disease resistance)?
Lactase persistance, Sickle-Cell anemia
fixity of species
Old thought that most animals, organisms and eukaryotic/prokaryotic cells remained a constant and that all physical matter/energy remained unchanged, no evolution, entropy, exc
Mendel
Recessive and Dominant Alleles, Segregation of Alleles, Homozygous, Heterozygous, Genotype, Phenotype
What are the differences between somatic cells and gametes?
Somatic cells= body cells Gametes= sex cells
Linneaus
Taxonomy (Hierarchical form of classification), Binomial Nomenclature, and Homo Sapiens classified.
Vitamin D synthesis
The absorption of Vitamin D through the skin, which is more difficult the more melanin you have.
genotype
The genetic constitution responsible for the a physical characteristic.
multiregional model
Theory that hominin populations in Europe, Asia, and Africa evolved into modern humans separately.
replacement model
Theory that modern humans first evolved in Africa and later dispersed, replacing previous hominins already residing in the other regions.
What does it mean that anthropology is a holistic discipline?
This means that Anthropology studies humans and cultures by paying attention the many details, in order to grasp holistic understanding of them. This often includes ethnographic research.
Lamarck
Transformational Evolution (Notion that a species could change over time/not fixed), Inheritance of acquired traits
Darwin
Transmutation and Natural Selection
arboreal vs. terrestrial
Tree-dwelling versus ground-dwelling
homozygous
When an individual has two of the same allele, whether dominant or recessive
opposable thumb
When thumbs can be moved around to touch other fingers, allows for grasping things with hands.
melanin
a dark brown to black pigment occurring in the hair, skin, and iris of the eye in people and animals. It is responsible for tanning of skin exposed to sunlight. The closer you live to the equator, the more melanin a population will have.
species
a group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding.
theory
a well-substantiated explanation of natural phenomena, supported by hypothesis testing and by evidence gathered over time.
brachiation
arm swinging, is a form of arboreal locomotion in which primates swing from tree limb to tree limb using only their arms.
diurnal vs. nocturnal
awake and active during the day versus awake and active at night.
Allen's Rule
body form or shape is linear in warm climates and more rounded and compact in cold climates. Round forms have a smaller surface area to volume ratios. Bergmann's Rule: body size is large in cold climates and small in warm climates. Large bodies have a smaller surface area to volume ratios.
How might anthropologists define culture?
both learned and instinctual behaviors
lactase persistance
continued activity of the enzyme lactase in adulthood. Since lactase's only function is the digestion of lactose in milk, in most mammal species, the activity of the enzyme is dramatically reduced after weaning
What might be the differences between induction and deduction as a form of reasoning?
deduction is "top down," general to specific, and uses prediction of consequence; induction is "bottom up," specific to general
species concept
defines a species as members of populations that actually or potentially interbreed in nature, not according to similarity of appearance.
principle of independent assortment
describes how different genes independently separate from one another when reproductive cells develop.
Why would a biological anthropologist be interested in linguistic anthropology?
development of language in hominids; language acquisition in infants; language capacity among primates; spread of language
sexual dimorphism
distinct difference in size or appearance between the sexes of an animal in addition to difference between the sexual organs themselves.
What were some common notions about biology prior to the scientific revolution?
fixity of species (all organisms were created in their current state), essentialism (essence of a species), young earth (Archbishop Usher- earths creation October 23, 4004 bc)
heterozygous
gene locus when its cells contain two different alleles of a gene.
How do anthropologists explain most of the physical (phenotypical) differences among human biological traits?
genetic traits vs. acquired traits
clinal variation
gradual change in inherited characteristics due to environmental factors, such as UV levels, temperature, latitude, etc.
What makes a good hypothesis?
has to be disprovable
natural selection
he differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, it is a change of heritable traits in a population over time.
What are some of the morphological changes in hominin skeletons as a consequence of bipedalism?
hips into a bowl shape, valgus angle lost, adducted toes, foramen magnum location
What is a bicultural approach?
interaction of culture and biology as an adaptive quality
How is skepticism defined and how does it apply to the scientific method?
its an exercise in rational thought and critical thinking
What are some key characteristics of strepsrhines (prosimians)?
large ears, sharp claws, nocturnal, arboreal, rhinarium nose, vertical clinging and leaping (VCL)
What is the scientific method and hypothesis testing?
observation, question, hypothesis, prediction, and test; either reject or support hypothesis
What are some specializations of biological anthropology?
paleoanthropology, anthropometry, osteology, forensic anthropology, molecular anthropology
hypothesis testing
precise repetition of an experiment or expansion of observed data to provide verification; the procedures by which hypotheses and theories are verified, modified, or discarded.
What are two important principles of Mendelian inheritance?
principle of segregation and principle of independent assortment
How is the co-variance of traits used to break down the myth of biological race?
racialized traits are clinal
sickle-cell gene
results in the abnormal form of hemoglobin that results in collapsed red blood cells, blockage of capillaries, reduced blood flow to organs, and without treatment, death.
Why might science be described as another way of "knowing"?
science as a product of culture; the concept of 'how' you know things is a product of culture
How did the concepts of transformational evolution, catastrophism, uniformitarianism, and competition relate to or help develop Darwin's evolutionary ideas?
scientific knowledge builds on previously developed theories
What were some of the challenges associated with early evolutionary thought?
society and religion, fixity of species, essentialism, and "young" earth
Bergman's rule
states that within a broadly distributed taxonomic clade, populations and species of larger size are found in colder environments, and species of smaller size are found in warmer regions
mutation
the changing of the structure of a gene, resulting in a variant form that may be transmitted to subsequent generations, caused by the alteration of single base units in DNA, or the deletion, insertion, or rearrangement of larger sections of genes or chromosomes.
founder effect
the reduced genetic diversity that results when a population is descended from a small number of colonizing ancestors.
fossil
the remains or impression of a prehistoric organism preserved in petrified form or as a mold or cast in rock.
phenotype
the set of observable characteristics of an individual resulting from the interaction of its genotype with the environment.
prehensile tail
the tail of an animal that has adapted to be able to grasp or hold objects. Fully prehensile tails can be used to hold and manipulate objects
gene flow
the transfer of alleles or genes from one population to another.
essentialism
the view that for any specific entity there is a set of attributes which are necessary to its identity and function.
Why are Sahelanthropus tchadensis, Orrin tugenesis, and Ardipithecus radius significant pre-Australopiths?
they are closest to ape-human divergence
What can anthropologists learn by studying primate behavior?
they can learn more about humans, and how we came to be who we are
What evidence do we have for tool use among primates? Why is this important for understanding human origins?
tools are associated with subsistence & this tells us more about us
genetic drift
variation in the relative frequency of different genotypes in a small population, owing to the chance disappearance of particular genes as individuals die or do not reproduce
What are some characteristics of primates and how might they differ from other living creatures?
versatile limbs, prehensile hands/feet, diet, intelligence, parental investment, social nature
How do primatologists explain the presence of monkeys (platyrrhines) in the New World? What makes them distinct in terms of their characteristics?
~ ~ flat, broad nose; nostrils point outward
Who were some of the early thinkers that contributed to evolutionary thought? What concepts did they contribute?
~ Charles Darwin & Alfred Russel Wallace both discovered the concept of Natural Selection (the theory of evolution). ~ John Ray - concept of species. ~ Carolus Linnaeus - Binomial Nomenclature (the basis of Taxonomy). ~ Jean-Baptiste Lamarck - Use/Misuse Theory. ~ George Cuvier - extinction and catastrophism.
Why is mtDNA significant for bioanthropologists?
~ Haplotypes (group of genes inherited from one parent) ~ Haplogroups (genetic population of a group of people who share a common ancestor on the matrilineal or patrilineal line) ~ can show the rate mutation throughout history
What were some of the earliest primates and which living primates do they tend to resemble?
~ Paleocene plesiadapiforms ~ Eocene euprimates (Adapids/lemur, Omomyids/tarsier) ~ Aegyptopithecus (anthropoid ancestor) ~ Miocene proconsulids, Sivapithecus, Gigantopithecus (early apes)
What is the major taxonomic division within the infraorder anthropoidea and how is it defined?
~ Platyrrines- new world monkeys ~ Catarrhines- old world monkeys, apes
Which primates are classified as apes? How are they distinguished from other primates? What makes them important to the study of humans?
~ Siamangs, Gibbons, Orangutans, Gorillas, Bonobos, Chimpanzees ~ lack of tail, quadrupedal on limbs
What is DNA and what is the difference between nuclear DNA and mitochondrial DNA (mtDNA)?
~ acids controlling cell functions ~ mtDNA- inherited from mothers, no mitosis or recombination occur, haplotypes/haplogroups
What is the modern synthesis of evolution?
~ darwinian and mendelian approaches ~ change in allele frequency over time ~ not goal oriented
Why might some chimp "violence" be considered partially due to researcher influence?
~ due to situational circumstances creating an 'unnatural circumstance'
What is the difference between genetic and acquired (functional) human traits?
~ genetic traits are passed down to offspring ~ acquired traits are a product (physical characteristic not passed down to offspring genetically) of the environment's influences on the organism
How do anthropologists approach the concept of human "race"? Is race a valid biological concept?
~ in accordance to geography ~ not a biological concept
What is polygenic inheritance and how is it different than mendelian inheritance? How does it relate to a discussion of discrete human "races"?
~ influenced by more than one gene ~ mendelian traits you get one or the other, while polygenic traits you can get both
How are precision grips and power grips different?
~ power grip= strong ~ precision grip= precise