Anthro 260 Final
Recessive
An allele that is expressed in an organism's phenotype if two copies are present, but is masked if the dominant allele is present. Phenotypically visible.
Thomas Malthus
An economist who was concerned with the population size in humans and resources, gave Darwin the idea that there was a struggle for existence
Give examples and dates of early Homo sapiens fossils.
Omo-Kibish S. Ethiopia 190 kya, Herto, Ethiopia, 160 kya, Qafzeh 9, Israel, 115 kya
Explain the placement of Sivepithecus on the phylogenetic tree
Relative to chimp, siva and orangutans share many derived traits: - mobility of wrist and elbow mobility that is seen in later apes flatness of face, no brow ridge, and shape of orbits are all much closer to orangutans
Fixity of species
States that all organisms are in a fixed and unchanging state for the entire history of earth.
Linneaus
Published Systema Naturae, standardized Ray's system giving us binomial nomenclature. ( Developed Tree-thinking, placed humans in the order of primates.
Allomother
a woman who cares for children that is not the biological mother of said children
sperm competition
competition between different individual's sperm in fertilizing an egg.
John Ray
Recognized species as groups of plants and animals that can interbreed, classified plants and animals with similarities and differences, and grouped similar species into genera.
Dominant
Refers to an allele that is expressed in an organism's phenotype and that simultaneously masks the effects of another allele, if another one is present
Polygenetic
Refers to one phenotypic trait that is affected by two or more genes
List evidence for the ecological hypotheses of primate cognition
Reject: monkeys seem to know little of what others know, and rarely practice deception apes know more possibly.
Theory
"a grown up hypothesis", a hypothesis becomes a theory after it has been rigorously tested and shown not to be incorrect time and time again.
synapomorphy
(shared derived traits)- a characteristic shared by two or more taxa because it was inherited from a more recent ancestor.
symplesimorphy
(shared primitive trait)- a characteristic shared by two or more taxa because it was inherited from a distant ancestor.
List evidence of extractive foraging among apes
- Orangutan and duriens - Aye-ayes and insect larvae - baboons and underground corms
What was the first member of our genus Homo?
homo ergaster
Explain how the particulate nature of inheritance can be reconciled with fact that most traits are continuous in nature.
- The particulate nature of inheritance, and Mendel's experiments, implies inherited variation is discontinuous. This is in opposition to the apparently continuous variation observable for many traits... And Darwin argued that adaptations arose through the accumulation of small changes... - Traits can be passed on from generation to generation through genes, and genes can keep their ability to be expressed while not always appearing in a descending generation - If multiple genes were involved in the expression of an individual trait, they could produce the diverse results observed.... - So, Many traits are not discrete features (e.g. yellow or green peas) but instead continuous (e.g. human height and skin color) which are the products of many genes...polygenic traits!
What are the derived traits of humans relative to other primates?
- bipedalism - chin - decreased sexual dimorphism - brain size - lumbar curve - speech - relatively hairless - longer gestation and maturation
If you were looking for early evidence of bipedalism, what traits would you want to find in a fossil creature?
- location of foramen magnum - lumbar curve - angled femur - bowl pelvis - adducted big toe
Biases in fossil record
- rich but incomplete - chances of becoming fossil = slim, finding one = slimmer - our view underestimates diversity of extinct creatures - dates of extinct species are always underestimates
What other major discoveries were made by Donald Johanson and his crew at Hadar?
- they found a knee that they believed to be bipedal - and at least 13 other individuals "The first family"
Explain why the benefits of a behavior must outweigh the costs if natural selection is to favor it.
- to be evolved and maintained, benefit must outweigh cost. - primate group living - primates realize these benefits enhance RS more than solitary - behavior that balances costs and benefits will have survival and reproductive advantages over behavior that doesn't
Explain the process of radioactive decay
-Different isotopes of an element differ in # of neutrons -Some are unstable and undergo radioactive decay which occurs at a constant rate.
Describe the characteristics of the Paranthropines
-Sagittal crest: enlarges attachment surface for temporalis muscle that works the jaw - huge molars - Flared zygomatics: make room for enlarged temporalis - all relate to heavy chewing
Is it possible that cannibalism could arise and/or be maintained by natural selection? Provide some examples.
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Theory of Mind
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What are two component that contribute to fitness? Explain them.
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Why is Australopithecus a good transitional species?
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a sequence of DNA on a chromosome, coded to produce a specific protein.
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a trait that has been around for awhile. (example: body hair among primates, chimps look more like gorillas than us because they retain ancestral traits)
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it can be used to determine whether a population is undergoing evolutionary changes.
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not many were willing to accept such a role and to do so seemed to be silly at best, but the role of early exploration was to get people to start thinking about change over a long period of time.
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Homology
A trait shared by two or more organisms inherited from a common ancestor.
5 things that must be true for a pop to be in H-W equilibrium
1) There is no difference in fitness attributable to allelic combination 2) No mutation 3) The population is large (effectively infinite) 4) No interbreeding with other pops 5) Mating is random
match species with descriptions: 1. sahelanthropus tchadensis 2. australopithecus afarensis 3. orrorin tugenensis 4. paranthropus bosei 5. adripithecus ramidus A. huge premolars B. Lucy's kind C. Bipedal pelvis, but divergent big toe D. Very little is known about its head E. Discovered in Chad
1. E 2. B 3. D 4. A 5. D
Name and explain Mendel's two laws of inheritance.
1. Law of Segregation states that an individual organism has two alleles for every gene, one inherited from its mother and one from its father. When this organism forms its own gametes, each gamete will receive only one of these alleles, and this process is random. 2. The Law of Independent Assortment states that separate genes for separate traits are passed independently of one another from parents to offspring.
Lamarck came up with a hypothesis for the evolutionary process. Explain his ideas.
1. The will to change 2. Inheritance of acquired traits 3. Law of use and disuse
Darwin's three postulates
1. There is a struggle for existence 2. variation in traits and behavior results in variation in fitness 3. Inheritance of variation
According to Darwin's theory of evolution by means of natural selection, what three conditions are necessary for natural selection to produce adaptations?
1. a struggle for existence - ability to expand is infinite but environment limits populations 2. variation in nature -fitness= survival and reproductive success 3. inheritance of variation -variation transferred from parents to offspring
Describe the process of becoming a fossil
1. body inaccessible to scavengers 2. quick burial 3. very dry conditions with little moisture 4. sedimentation: layers = hard 5. petrification (organic materials are replaced by inorganic ones) 7. dissolved organic material leaves an imprint (cast) 8. later filled in with minerals (mold) 9. and wait
Explain how group living can be an effective anti-predator strategy.
1. detection: more eyes to see predators, less time scanning 2. deterrence: more individuals to scare or distract 3. dilution: in groups, single individ. Is less likely to be caught
Hypotheses put forward to explain why some apes evolved the ability to walk on two legs.
1. efficient way to travel on ground. Forests became scare and apes need to walk further to get to forested areas 2. thermoregulation: less body exposure to sun, more wind hitting front, sweating works better. 3. frees up hands: carry, hold stones, sticks, spears 4. good for harvesting food from trees
What 3 factors does reciprocal altruism require?
1. frequent opportunities to interact 2. keep track of help given and received 3. must only help if receive help
If infanticide is a strategy, what predictions might one make? Are these predictions supported by any observations or data?
1. infanticide will be linked to changes in male residence/status 2. Males will kill unweaned infants 3. Males will not kill their own offspring 4. Infanticidal males will gain reproductive benefits Seen in OWM, NWM, apes, lions, rodents, birds
Explain 2 ways for altruism to evolve via NS.
1. must be directed at other altruists, relatives carrying the "altruism gene". Altruistic acts favored by kin selection when rb > c, 2. Through reciprocal altruism: take turns giving/receiving
What is required to manipulate social relationships to one's advantage?
1. recognize individuals 2. tracking nature of social relations between second and third parties 3. anticipating behavior of other animals
How old are the first tools? Where were they found? Who made the first tools?
2.5-2.6mya. They were found near the Olduvai Gorge, and Gona, Ethiopia. A. garhi is a good candidate, but others were around at the same time.
What behavioral evidence is there for bipedalism at Laetoli?
3.5 mya, footprints with adducted toes - one individual was 4'9", other was 4'1" - similar to those made by modern people can infer ideas about social life
When did humans enter the Americas? From where did they originate?
30-20k years ago, Beringia
Vestigial Trait
A part of an organism that doesn't have a particular function anymore - seemingly non-functional, [but had functionality in a recent common ancestor (garrett b. michelle p. xanthe d.)]. EX: Appendix in humans and pelvis in the whale
Olduvai Gorge
A ravine in East Africa, Tanzania where Oldowan tool technology was discovered along with many ancient fossil remains.
What does it mean to have a smaller intermembral index?
A smaller number means you have longer legs compared to your arms. A larger number means you arms are longer than your legs.
Why is defining a trait as a synapomorphy always RELATIVE? Provide a few examples to illustrate your point.
A synapomorphy is a relative term depending on what you are looking at. Synapomorphies will be shared among all the organisms that are being studied, so we can lump these together in a group. Yet this does nothing to classify the organisms in the group. But, if you looked at a broader group, what was a symplesiomorphy before may now be a synapomorphy (the separating factor between groups). example with mammals. - symplesiomorphy = all mammals are warm blooded. this doesn't allow us to see which mammals predated which (because all are warm blooded) instead it defines the group as a whole - but if we are looking at tetrapods, we can use warm bloodedness as a synapomorphy to show when mammals arose because it arose later within the broader group of study. it all depends on the group being studied.
Radiometric dating
A technique used to date materials such as rock. Usually based on comparison between observed abundance of a naturally occurring, radioactive isotope and its decay products using known decay rates.
Describe the Achuelian handaxe.
Achuelian hand axes are bifaces (cores flaked on sides to make cutting edge), one round end to fit in hand, other cuts. Hand axes all have the same proportions regardless of size,unchanged for nearly one million years all over the world (implies common plan), best suited to butcher carcasses
Coffee
Africa
Define agriculture. What effects did the domestication of plants and animals have on our species?
Agriculture is the production, processing marketing and use of foods fibers and byproducts from plant crops and animal. it allowed our populations to boom in numbers and expand. changed fundamental ways in which humans interact with their environment, change in diet, helped found the rise of complex societies/cities/technology, creation and dependence on superfoods
Why is reproduction so important? Place answer in context of how NS works.
All adaptations ultimately channel their effects thru reproduction - carries on org's survival because it passes on half of its genes to supply next generation with traits - if these traits increase RS, they are favored by NS. Why? B/c if a trait increases fitness and is heritable, trait is passed onto next gen, changes gene pool and evolution occurs!
Autosome
All chromosomes, except sex chromosomes, that occur in pairs all in the somatic cells (not the gametes).
Discontinuous Variation
Also called discrete variation. Phenotypic variation in which there is a discrete number of phenotypes.
Provide an experiment that you could conduct to test Lamarck's hypothesis.
An Experiment that could be done to prove the Lamarck hypothesis would be to have two dogs and make them blind and have them mate. Then have the next generation of offspring, make them blind and have them mate and so on and so forth. Eventually, due to the disuse of the trait of sight, the offspring stemming from that original dog would all become blind from birth. Another experiment could be to cut the tails off generations of mice, with the Lamarck evolutionary process, eventually the mice would have no tails.
Relative dating: biostratigraphy
Comparing fauna or flora in one strata at a site with that in another site which has already been dated.
Mechanistically, how does the bipedal body of hominids work?
Angle of femur and location of knees under body make it more efficent. Abductor muscles tighten to oppose torque these attach on surface provided by thicker illium and longer femoral neck
What evidence supports the idea that Neanderthals were hyper-cold adapted?
Animals in cold places are large and stocky, with short limbs, Neanderthals had short arms and legs with short digits in line with this trend, also known as Allen's rule
Describe characteristics of Australopithecines
Ape-like prognathic face, generalized diet, bipedal: - angled femur, horizontal ankle joint, knee of Hadar, Laetoli footprints, foramen magnum, bowl-shaped pelvis still adept to life in trees, small bodies ape like development and brain size, pronounced sex. Dimo -ntermediate teeth, jaw, skull btw apes and later hominids
Base Pair
Are the building blocks of the DNA double helix. Consist of Thymine, Guanine, Cytosine, and Adenine. Thymine and Adenine pair together and Guanine and Cytosine pair together.
Birth weight and weaning weight graph. What does the relationship indicate? Why is the pattern not random?
Babies are weaned at about 4 times their birth weight and this shows that NS has decided this is optimum for the child to get the nutrients it needs, etc. Humans deviate because we have other options to milk that give the same nutrition benefits so we are able to wean our children faster...boosting female RS
Why is Professor Kemp obsessed with eye spots?
Because even though the organism cannot see, feel, or acknowledge the presence of eye spots, it continues to persist in future generations and ward off predators. Eye spots are a prime example that evolution is not driven by desire or intelligent recognition of what traits will allow individuals to live longer. From this action we can see that those without these spots die out causing those with spots to express a higher fitness and passing of genes.
Why is there typically a division of labor in the efforts of modern foraging groups?
Because high skill tasks favor division of labor, and if foraging tasks are hard to master then specialization is necessary.
Why is Lucy such a famous fossil discovery?
Because she is an almost complete specimen and it was one of the first discoveries showing bipedialism in early hominids
In terms of reproduction, why does NS act more strongly on males than females?
Because there is more variation in male reproductive success - males can produce many child w/o the burden of pregnancy while women are limited by IBI, caring for children, etc.
altruism
Behavior by an animal that is not beneficial to itself (may even harm themselves), but that benefits others
Strategy
Behavioral mechanisms that produce particular course of action in particular contexts. Example: optimal foraging. Does not imply conscious reasoning. Benefits and costs of strategies effect fitness.
Costs and benefits of group living
Benefits: multi-mates, social interaction, safety, shared info, better access to resources costs: inbreeding, not enough resources, infighting, more disease, cannibalism, infanticide, competition
Describe aspects of the post-cranium of australopithecines
Bipedal, foramen magnum bowl-shaped pelvis and angled femur GahriL thigh long relative to arm, forearm ape-like in relative length. Sexually dimorphic bodies for men/women
Explain how infanticide can be viewed as a stable reproductive strategy taken by males.
By killing the unweaned infants, females will become available to mate sooner and the new male will breed with them. Reassures that these new offspring are his. - residence is short-lived so this enhances male mating opportunity. - is a sexually selected male reproductive strategy
What strategies do females take to enhance their reproductive success? Explain each one.
Care: nourishment, transportation, warmth, protection Competition: female RS limited by access to resources Cooperation: members of group helping others take can of young.
Where was Sahelanthropus tchadenensis discovered? To when does it date? What about this creature indicates bipediality?
Chad, Africa 6-7mya Placement of foramen magnum under skull
Copernicus
Challenged the notion that the earth was the center of creation.
Charles Darwin
Charles Darwin went on the Voyage of the Beagle from 1831-1836 and later published 'The Origin of Species' in 1859. Darwin is significant because he came up with the theory of Natural Selection with is still very prevalent today.
What are the major difference between Collected Foods, Extracted Foods, and Hunted Foods?
Collected: Easily picked up - berries, hanging fruit, Extracted: Learned way of removing and making a food edible -> Removing the acorn and leaching the toxins, Hunted: Animals, using tools
What is complex foraging? How did the adoption of complex foraging shift the evolutionary trajectory of sexually dimorphic bipeds to roughly sexually monomorphic modern humans?
Complex foraging techniques allow humans to acquire highly valuable or otherwise inaccessible foods Foraging takes years to learn, extracting resources require skill, strength, detailed knowledge. Thus, high skill tasks favor division of labor (specialization) between men and women because foraging tasks are hard to master. and food sharing is mandatory because it reduces the risk of failure/starvation. reduced dimorphism: men produce bulk of surplus calories, if kids rely on male's contribution (b/c of longer juvenile period) selection favors INVESTING MALES. so, male-male competition reduced, and this is linked to reduced sexual dimorphism in human societies.
What was behaviorally new about first members of the genus Homo?
Controlled fire, Relied more heavily on hunting, new toolkits and blade technology and knowledge may have been passed along by teaching. expanded to much more of the planet.
Why are convergent traits so cool
Convergent traits are very interesting because they show how a handful of different organisms solve problems by independently coming up with similar solutions.
How does radio-carbon dating work.
Cosmic radiation changes N14 to C14 (radioactive) which is an unstable isotope that decays back to N14 after death (b/c C is no longer replaced). Ratio of C12 to C14 will be identical to the level in the atmosphere. Requires calibration against C12 to C14 of ancient atmospheres. Dates remains up to 40kya
Benefits and costs of big brains
Costs: expensive Benefits: good for learning and flexible, problem solving. (good when things change) - good for solving complex ecological and social problems
What is culture? How can it be studied from an evolutionary perspective?
Culture is learned(from other people), shared (must be understood from "population thinking"), symbolic, dynamic. evo perspective: population-thinking about culture change How does the ability to acquire ideas, beliefs, and values from others via social learning affect the frequencies of behaviors at the level of a population through time?
What is translation and where in the cell does it take place?
Cytoplasm, outside the nucleus and translation is the process in which cellular ribosomes create proteins. It is part of the process of gene expression.
Why can DNA tell us something about our relationships that other data (i.e. family trees) cannot?
DNA has all the information needed to make various connections with each other
ancient DNA
DNA isolated from things long dead
Explain how differences in DNA sequences can ultimately lead to differences in phenotypes.
DNA must lead to different phenotypes to play a role in evolution (for others to gain advantageous attributes). It does this in 3 way: 1. DNA in protein coding genes: Specify the structure, or codes for proteins. this is crucial in the function of living things example: enzymes 2. DNA in regulatory genes: Determines conditions when protein coding genes will be expressed this allows cell differentiation in complex, multicellular organisms examples: liver cells, nerve cells, muscle cells 3. DNA specifies structure of different kinds of RNA: RNA is crucial to important cellular function example: protein synthesis, gene regulation and expression, cell replication
How does potassium-argon dating work?
Dates age of volcanic rock that sandwiched fossil (not the fossil itself)Volcano erupts rock gets very hot, argon boils out. After cooling, isotope K40 decays to Ar40. Any Ar40 today can only be result of radioactive decay b/c none was present when rock formed. Measure ratio of K40:Ar:40. High Ar:K ratio = older specimen. Dates up to 500kya
Explain the placement of Aegyptopithecus on the phylogenetic tree
Derived dental formula. (2.1.2.3) so definitely after NWM Tail indicates that it cannot be after OWM Still very primitive overall
Why does "descent with modification" reveal the cousinhood of all life?
Descent with modification reveals the cousinhood through all life by making seemingly unrelated species relatable through physical and biological features. EX: A human can be related to a jellyfish in the fact that we both are compiled from cells and Humans and dogs by the fact that we have 5 digits
Explain the role of early exploration on evolutionary thinking?
Discoveries of the fossils of extinct species and geological formations suggested that the Earth was much older than it was religiously conceived to be. As the formation of geological structures was gradual, so too were the appearance of humans from a non-human ancestor. The first who noted these contradictions in religious belief faced much ridicule of their peers
Describe the diversification of hominids between 4-2 million years ago.
Diversified b/c they ventured out of forests. Australopithecines: multiple species, ape-like prognathic face, generalized diet adaptations, fast development Paranthropus: 3 species, ape-like prognathic face, diet of hard items Kenyanthropus: 4-7 species coexisted
What are some examples of convergent traits and how are they seen as a solution?
EX: Wings - many species have wings and for the most part, they came up with these devices through independent means when different problems were presented to them. Of course, these traits had evolved
Savannah Hypothesis
Ecological influences drove an ape-like ancestor from trees into a life in open savannah habitats. Thought to have developed bipedality to counter predators by looking over tall grass.
2 basic hypotheses about why primates have such large brains
Ecological: favor brains because primates need to know where to find food, cognitive maps, foods hard to extract. Social: live in large groups and living with others favors ability to flexibly deal with conflict and cooperation.
Provide an example of Mendel's Law of Independent Assortment from what you know about human variation
Example for Law of Independent Assortment can be seen in the fact that the color of your hair is independent on the color of your eyes or vise versa. The color of your hair is controlled by a different allele than the one that controls eye color.
Explain how the scientific method works.
Facts are data from which conclusions can be drawn (observations). Then a hypothesis is a personal explanation of a phenomenon (predictions that can be tested). A theory is like "grown up hypothesis." A hypothesis becomes a theory after it has been rigorously tested.
Gregor Mendel
Father of modern genetics
What is fitness?
Fitness is the relative reproductive success of an organism
What is the ultimate limiting factor to a females reproductive success? Why? List other factors that limit a female's lifetime RS.
Food availability/nutritional status carry/conceive/lactate = greater caloric requirements Also, dominance ranking. Higher=more access to better resources. RS of children play into rank.
Why is phylogenetic reconstruction difficult using fossils?
Fossils usually aren't complete and they don't tell the whole story of a species from a single specimen. So missing data misleads us to falsely simplify actual phylogenetic relationships.
Skull bones, counter-clockwise beginning at top
Frontal (forehead), maxilla (mouth), mandible, zygomatic (cheek bone), temporal (side of head), occipital (rear, underside of skull), parietal (back of head)
Examples of low-value, widely distributed resources. What type of competition does this encourage?
Grass blades, flowers, wild celery scramble competition
Which primates live in groups? Which are solitary?
Groups: Gorilla, chimps, baboons, howler monkeys lemurs Solitary: Orangutans
What evidence suggest that modern human coped better with the environment than did Archaic Homo (e.g. Homo neanderthalensis)?
Had longer life spans,UP men sometimes lived to 60, UP women rarely lived past 40, Less vulnerable to injury and disease,Show less evidence of trauma, illness,May have been better nourished,May have managed encounters with dangerous animals better, Lived at higher population densities
Buffon
He wrote Natural history, not an evolutionists but thought change was possible. Buffon noted that despite similar environments, different regions have distinct plants and animals, a concept later known as Buffon's Law
Where was Orrorin tugenensis discovered? To when does it date? What indicates it was bipedal?
Highlands of Kenya, Tugen Hills near Lake Baringo 6mya thigh bones are more like human thighs. Long femoral neck and angled femur suggest bipedalism.
What is the "Chihuahua Problem" and how is it solved?
How do we get a chihuahua and all the other variations of dogs from a wolf? Reshuffling of genetic material during meiosis can bring out a tremendous combination of variation. Mutation and segregation explain how a species can move beyond its initial range of variation.
Allen's Rule
Humans living far away from the equator tend to have shorter limbs and are stockier.
Explain some fundamental difference between the foraging behaviors of chimpanzees and modern
Humans spend a high proportion of their time on extracted and hunted foods, Chimps spend a high proportion of their time on collected foods.
Bergman's Rule
Humans tend to have smaller bodies close to the eqautor, those in cold climates have larger bodies
How can differences in DNA sequences lead to difference in fitness?
If a change in sequence results in a trait that is more favorable to it's current environment, or resistant to harm when the environment chances, this can lead to increase in fitness. On the other hand however, a change in genetic sequence can also produce harmful effects on fitness and the individual. (ex: a butterfly with 1 shorter\wing)
What does it mean when a population is in the Hardy-Weinberg equilibrium?
If a population is in this equilibrium, then the genotype frequencies at a single locus will remain the same after one generation. The equilibrium frequencies will be a function of the allele frequencies at the locus.
Explain how natural selection causes changes in allele frequencies.
If a trait that is more advantageous to an organism's survival and reproductive success is selected for over one that is not a selective advantage, there will be an increase in the gene pool for alleles that produce the advantageous trait and a decrease in the alleles that produce the less advantageous trait.
Casts
Imprint left after organic material is dissolved
Alfred Russel Wallace
In 1854 he came up with an explanation for evolution, same idea as Darwin around the same time. Presented at the Linnaeus society jointly with Darwin. arrived at the same conclusions as darwin,but he had less evidence than darwin, helped spur darwin into writing his book.
With what type of social/mating structure is sexual dimorphism most pronounced? Why is this the case?
In one-male, multi-female groups. Because the male has to fight off other males from outside the group.
What is transcription and where in the cell does it take place?
In the nucleus and is the first step of gene expression, in which a particular segment of DNA is copied into RNA.
Is "Intelligent Design" a scientific theory? Explain your answer.
Intelligent Design isn't a scientific theory because it can't be rigorously tested, and this is part of the definition for a theory. There is no definitive way to work with the proposed designing "agent" or to show how or why it created anything.
Taxonomy
Is concerned with phylogenies for naming and classification purposes. Carl Linnaeus was a biologist and is known for being the Father of Taxonomy.
What does Archaeology as Long-Term mean?
Long term ethnography or study of the long term culture that surrounds hominids...uniformitarianism
Why is the term "missing link" a misnomer? What is substitute for this phrase?
It assumes there was one link connecting apes and humans, but once one "link" is found, it creates 2 more missing links - better termed as "transitional forms" - we are looking for creatures with a mix of ancestral and derived traits
What does the timing of this event indicate about how humans initially reached the Americas?
It was a very different climate, very cold! the timing was perfect to do this on foot and it took a very long time.
Explain the placement of Proconsol on the phylogenetic tree
Lacks mobility of elbow and wrist that is seen in living hominids, so it must have been before Siva - no tail indicates it shares a derived trait with those that come after OWM very ape-looking in general
Why is it likely that the earliest hominids used tools? Why might it be the case that we have we not found tools that are older than 2.5 million years old?
Likely because evidence of butchering. on bones and specific sites with animal remains The use of tools in apes can be used to argue in favor of tool-use as an ancestral feature of the hominin family. Tools were therefore in all probability used before the Oldowan. We haven't found tools older because bone or some other kind of toolthat does not preserve well in the archaeological record as well as stone may have been used before 2.5 mya.
Explain how the distribution of resources can influence social structure and primate behavior
Low-value widely distributed: scramble competition Unstable hierarchy → no allies, weak bonds, male/female dispersal high-value clumps: contest competition → dominance hierarchy → value of allies, female relationships and dispersal patterns
Aye-aye or another lemur, where are you? a. madagascar b. japan c. south america d. australia
Madagascar
What were some of the last places on Earth reached by humans. Approximately when did they arrive in these places?
Madagascar 2000 years ago and polynesia 3000 years ago
Galileo
Major player in the scientific revolution helped pave the way for future scientists such as darwin.
Infanticide
Male that is new to group kills off all offspring of old leader
What are strategies males take when living in one-male/multi-female groups? Why?
Males compete for access to groups of females, after joining commit infanticide - this ensures that all the offspring from here on out are his
What are strategies that males take when living in multi-male/multi-female groups? Why?
Males compete for dominance rank, high ranks monopolize females, distant fathers. - because male RS in these groups depends on rank - so it ensures high ranking males are breeding the most
Describe some of the behavioral changes that are associated with early members of our species? Was there a revolution or gradual change that lead to our evolution of complex behaviors. Explain.
Mode 4 blade tools and more diversified toolkits with more varieties of materials, possible trade networks,longer lives, higher pop densities, less vulnerable to injury/disease, buried their dead with ceremony, first artists?, first paintings (le chauvet, france 32kya). gradual evolution in africa, revolution is just an illusion from sampling error
How did new variation--new characteristics--arise in a population?
Morgan showed that a new gene could arise in a population as a result of spontaneous change in an existing gene. (mutation)
What does the morphology of Ardipithecus ramidus suggest about its form of locomotion?
Morphology suggests it was a biped. Wide blades of pelvis, one that is more like humans. This would've suggested the femur was about a 75 degree angle, making it walk upright.
Kin selection
Natural selection in favor of behavior by individuals that may decrease their chance of survival but increases that of their kin (who share a proportion of their genes)
How is natural selection like a near-sighted mountain climber that has forgotten her glasses?
Natural selection is blind and does not always reach the best possible solution to a problem. A mountaineer that has forgotten her glasses will follow the rule of "always go up" because even though she cannot see that well, she knows to reach the top of the mountain, she needs to keep going up. So, natural selection will follow this same rule and avoid valleys, even though this may help it get from the local optimum to the global optimum.
Why was a there a seeming problem between Darwin's theory of Natural Selection and Mendel's laws?
Natural selection, the guiding force of evolution, could operate only on variation that already existed in a population.
Why can organisms largely be classified based on nested similarities?
Nested similarities feature the recent common ancestry of specific traits between organisms. In this manner, organisms can be classified based on these related characteristics.
Scramble competition
No one individ. Can limit access to a resource from others. Food goes down when pop goes up. Limited resources Dense population, all organisms compete to survive, all die.
One argument for the evolution of bipedalism is that it freed the hands to carry tools. Is this hypothesis consistent with the evidence from the fossil record?
No, scientists know that tool use, bigger brains, speech and complex material culture appeared AFTER bipedalism. tool use 2.6mya, brain size 2mya and bipedalism 6-7mya.
Sunflowers
North America
Describe the Neanderthals cranial features.
Occipital bun, defined brow ridges, low forehead midfacial prognathism
earliest stone tool technology known
Olduwan
How did Darwin's participation on the voyage of Beagle influence his ideas about the fact that life on earth evolves via natural selection?
On Darwin's Voyage of the Beagle he observed the finches which were very important to Darwin's idea that those species with more advantageous biological characteristics survived to produce offspring. He noticed that the variation in birds on the Galapagos Islands represented varieties of the same general kind of bird (finches), and he concluded that species are not stable. He later developed the ideas he came up with on the Voyage of the Beagle and published them in 'The Origin of Species' in 1859
Allele
One or more alternative forms of a gene. Gene variation.
Explain the role the of the waist-to-hip ratio in an evolutionary context.
Optimal levels of sex hormone- signals reproductive status Indicates good health Increased likelihood of pregnancy Optimal levels of sex hormone
Continuous Variation
Phenotypic variation in which there is a continuum of types. Example: human height.
Why reconstruct phylogenies? Explain.
Phylogenies are a basis for classification and identification of species, which allows us to observe how evolution has proceeded. Phylogenetic trees can also help us understand behaviors and functions of different species.
Phenotype
Physical expression of a genotype, it may be influenced by the environment.
Fossil
Physical remains of part, or all, of a once living organism. Mostly bones and teeth that have become mineralized by the replacement of organic material with inorganic material.
Permineralization (petrification)
Pores in tissues are slowly replaced by minerals in percolating water. - preserves hard and soft tissues
How great was the level of sexual dimorphism exhibited by Australopithecines?
Prominent, but decreasing form earlier ancestors. Height/weight differences
Examples of high-value, clumped distributed resources. What type of competition does this encourage?
Ripened fruit, fruiting trees, fresh leaves, corn, water leads to contest competition. Rank affects access to resources, females will strive for high rank. females benefit from help in competitive encounters
Describe Olduwan tools
Rock tools found in Olduvai gorge. Flakes are made from the core, one core can make up to 30 separate flakes. Flakes are made from striking one rock at the core at an angle.
_____ competition occurs when resources are distributed evenly across the landscape, and because animals cannot monopolize on them, they do not compete over them directly
Scramble
Intersexual selection
Selection favors traits that make males more attractive
What is meant by "nested set of similarities"? Why does speciation lead to this?
Shared recent common ancestor and closeness depicted in a tree or other diagram.
Monkey hanging by tail, where are you? a. madagascar b. se asia c. south america d. mainland africa
South america
Spider monkeys weigh approximately the same as howler monkeys, yet spider monkeys have a brain twice the size. Why might this be the case?
Spider monkey's main diet consists of fruit, while howler's is leaves. Fruit is more more nutritious and can therefore support the caloric requirements of a big brain whereas a howler's leaves cannot.
List evidence for the ecological hypotheses of primate cognition
Support: primates meet the 3 requirements of manipulating social relationships to one's advantage. Neocortex and group size.
Why are symplesiomorphies not useful in cladistics?
Symplesiomorphies are characteristics shared by 2 or more taxa because it was inherited from a distant ancestor. These are not useful in cladistics because they don't do anything explain evolutionary relationships. It takes recently (or shared-) derived traits, synapomorphies, that differ between organisms in the group being studied to see when one organism branched from another and see the evolutionary relationship between organisms.
Molecular Clock
Technique in molecular evolution, that uses fossil constraints and rates of molecular change, deduce the time in geologic history, when two species or taxa diverge
Describe aspects of the cranium of australopithecines
Teeth and jaws: less sexually dimorphic canines than apes along with apical wear and side wear prognathic brain size from 400-500cc, chimps about 370cc, us 12-1500
Name the contribution of the following to our understanding of evolution: Charles Lyell
Termed and explained uniformitarianism which is the theory that processes that occurred in the geologic past are still at work today.
According to lecture, what is significant about the first cave paintings?
That early humans had the ability to recreate images or scenery that they had seen in mediums such as the cave paintings. they were drawing what they saw.
Francis Bacon
The Baconian method (the scientific method).
What is the ultimate limiting factor to male mammals reproductive success?
The access to mates
Gene
The basic unit of inheritance
Explain the role of early discovered fossils on evolutionary thinking?
The discovery of fossils did not support the commonly held belief that all living beings had been created by God at the same time and continued to persist, today. The "existence" of extinct species allowed for people to start thinking about ancestry and the relationships between different species, specifically the extinct and the existing.
Let's say that the camera style eye (the kind we have) is superior to the compound eye (such as possessed by dragonflies). Why won't the dragonfly evolve a camera style eye?
The dragonfly won't evolve a camera style eye because in order to do so, it would have to go into a valley, or have worse solutions to the problem in order to get to a better solution...and this is not how selection works. Selection avoids valleys.
Great Chain of Being
a strict, religious hierarchical structure of all matter and life, believed to have been decreed by God
Why is the age of a fossil species always an underestimate of the true age?
The entirety of a species does not become fossils, it is most likely that we get a fossil from the middle of the lifespan of a species. Not likely to find the earliest or very latest fossils. Therefore we don't know the true age or lifespan of a species
Explain Hamilton's Rule
The evolutionary benefits of altruistic behavior to the kin group outweighs the cost to the individual acting altruistically, rb > c, equation for when altruistic acts will be favored by kin selection.
Lamarck
The first to propose a hypothesis of the evolutionary process. 1. The will to change 2. Inheritance of acquired traits 3. Law of use and disuse
Uniformitarianism
The idea that what is happening today, was happening long ago. Ex. Hunter-gatherers as they exist and use subsistence patterns today, did the same in the past.
What does it mean to have a larger brachial index?
The larger it is, the larger the radius is relative to the humerus. So you would have a relatively long radius
What does it mean to have a larger Crural index?
The larger the Crural Index, the longer the tibia is relative to the femur. A lower number means you have a longer femur.
Why do humans have a seemingly insatiable appetite for sugar, salts, and fats?
The reason that humans have an insatiable appetite for sugar, salts, and fats was because these were hard to come by before humans adopted agriculture. But now, we are in an disequilibrium, where we are eating sugars, salts, and fats when we should not be doing so.
What did Dobzhansky mean when he stated "Nothing in biology makes sense except in the light of evolution"? Provide some examples.
The relationships between organisms and their related traits cannot be scientifically explained without considering evolution. For example, the existence of fossils of extinct species with similar traits to modern ones.
socioecology
The scientific study of how social structure and organization are influenced by an organism's environment.
mitochondrial Eve
The source of all Mitochondrial DNA of modern human
Chromosome
The strand of DNA found in the nucleus of eukaryotes that contains hundreds of thousands of genes.
uniformitarianism
The theory that processes that occurred in the geologic past are still at work today. Termed by Charles Lyell
Why are closely related species similar?
They are closely related because they share a more recent common ancestor.
To what might the characteristics of the Paranthropines been in response to?
They suggest they may have been specialized for eating tough or hard food, like nuts, seeds and meat.
Describe aspects of Neanderthal culture and/or behavior? Were these guys the brutish creatures we often see depicted the media?
They weren't stupid. Neanderthals seem to have lived short, difficult lives.Life expectancy 40-45 years, used shells and pigments, accomplished big game hunters, hyoid bones = maybe speech?, bury their dead = abstract thinking, jewelry, disease/injuries, interpersonal violence, some survived injuries = compassion for others
The fact that natural selection removes variation from populations seems counter-intuitive to evolution proceeding by this process. Why was this a conundrum for Darwin?
This was a conundrum for Darwin because the fact that there is variation is one of his 3 conditions necessary for natural selection. If there is no variation, natural selection cannot produce adaptations.
Descent with Modification
Traits that have been modified from a common ancestor. EX: The mammoth had a fused radius and ulna, whereas branching ancestors have a separate ulna and radius.
What is the fundamental difference between male and female mammalian reproductive biology?
Variation in Male RS >> Female RS Females: obligated to invest, carry/conceive/lactate Males: more options. Invest when hard to find mates or when fitness of kin raised by one parent is low.
Explain how variation ultimately arises and can be maintained in populations (using an example may help).
Variation ultimately arises in populations due to mutation. Mutations are the ultimate source of variation. Low mutation rates can maintain variation as some variation is protected from selection in polygenic traits. (think of them being shielded) This is an advantage of being a diploid. beak depth in finches is an example: shallow beak deep beak - + + + - + - + - + - + + + - - - + - - - - + +
What can we argue logically about the type of ancient hominid from which we evolved? Why?
Was bipedal, no tail, chin, language etc. reduced sex. Dimorph, larger brains, larger body size, slower growth rate Because we are very derived compared to many other hominids and we must have acquired these traits along the way somewhere.
How can evolution be viewed as fact, hypothesis, and theory?
We can look at what the definition of a fact, hypothesis and theory are according to Francis Bacon. Facts are data from which conclusions can be drawn, they're observations. Evolution is an observable fact because it is observed that species change through time, through the discovery of fossils and the simple fact that nothing is perfect. A Hypothesis is a provisional explanation of a phenomenon, it makes predictions that are testable, most importantly a hypothesis must be falsifiable. Evolution is a phenomenon that has happened throughout history, it can be viewed as a hypothesis through the lens of Lemarck who saw evolution via the inheritance of acquired characteristics. Or by Darwin's hypothesis of evolution through the means of natural selection which has since gained theory status. A Theory is like a 'grown up' hypothesis. A hypothesis becomes a theory after it has been repeatedly tested and proven not to be wrong. A hypothesis can never be proven correct, it can only be refuted. Darwin's theory of Natural Selection does have points that are missed but has yet to be proven wrong, this is why it has maintained it's theory status.
How is DNA evidence used to date the emergence of modern humans? To when and where do the DNA data place the emergence of modern humans? Is this consistent with the fossil evidence?
We can use DNA specifically mitochondrial DNA to trace maternal lineages. DNA places Humans at 100-200k years ago. appearance of modern h. sapiens in Africa about 200kya and a population migrated out 200,000-100,000 years ago
A interesting question posed by others is "If we evolved from apes, why are apes still here"? How can this be reconciled?
We didn't evolve from apes.We share a common ancestor with apes and have varying physical similarities through our biological relationships. We evolved in separate locations under different conditions and surroundings.
Extended dependency during childhood is a key feature of humans. According to the lecture, how have we coped with this challenge?
We have coped with this through cooperative breeding strategies. offsets environmental (resources/predators) and social risks (deadbeat dads/cultural norms), allows for greater RS, increases survivorship, nutritional gains/child growth, shield from dangerous activities, attachment and bonding, decreases child abuse, increases maternal responsiveness,
When are males predicted to invest in their offspring? Provide basic statement that answers this and provide a few specific examples when males invest.
When mates are hard to find (widely separated), fitness of kin raised by 1 parent is low, when females mate at same time. (when there is only access to one female, or when their child is too weak and needs extra care and protection) when infants are big, litter > 1, high risk of infanticide/predation
Convergence
When separate organisms are presented with a relatable problem and independently come up with a similar solution. EX: Wings, Not homologous, it is independent evolution. Demonstrates that the evolution of complex traits and or behaviors is quite likely.
Explain how the distribution of resources can dictate whether females are philopatric or whether they disperse.
When there is a lot of resources in one area, females become philopatric: stay near or in an area. When resources are seasonal, spread out, etc. they move Females develop relationships with allies if they rely on them, they prefer their kin as allies.
Should lambs and asparagus be classified together? Why or why not?
Whether they should be classified together or not depends on the characteristic one is observing. For throughout various generations. They are NOT based on a common ancestor.
What did Dobzhansky mean when he stated "without that light [of evolution] it becomes a pile of sundry facts some of them interesting or curious but making no meaningful picture as a whole"?
Without a means to classify or explain variants of the same genus, facts about various organisms have no meaningful relationship with other organism and with ourselves.
Unbiased Cultural Transmission
a "naive" individual choose to copy a behavior or a "teacher" at random from within the population.
Provide an example of Mendel's Law of Segregation from what you know about human variation
a couple has an EQUAL chance of producing a son or a daughter
Phylogeny
a depiction of evolutionary relationships. EX: an extended family tree
FOXP2 Variant
a gene that has been implicated in the development of speech and language.
What is the Hardy-Weinberg Equilibrium?
a mathematical model in population genetics that reflects the relationship between frequencies of alleles and of genotypes
Menopause
a period in a woman's life where her reproductive success goes down and then stops after a certain age
Alloparent
a person who takes care of children that are not the biological parents of said children
Cost
a price that must be paid (expending energy in search of food)
Hypothesis
a provisional explanation of a phenomenon, makes predictions that must be testable and must be falsifiable. It can never be proven correct, it can only be refuted.
Mutation
a random change in a gene or chromosome, creating a new trait that may be advantageous, deleterious, or neutral in its effects on the organism
What is meant by cumulative culture?
accumulation of innovations in these cultural items that haven't just been passed person to person, but through generations.
What does the DNA of Neanderthals indicate about their relationships to modern humans?
admixture is small, but significant and occurred after early modern people left africa. common ancestor between us and neandertals is about 550,000-690,000 years ago. 27 differences were seen compared to the human mtDNA reference sequence. about 550k-690k years ago. neandertals are not more closely related to one human population than another. not much genetic diversity within neadertals, but very distinct from modern humans.
The adoption of agriculture is often seen as correlated with the rise complex societies and inequality. What is the link between the domestication of plants and animals and societal complexity and structure? Are agriculturalists the only human populations to have exhibited complex social structure?
agriculture is the basis for complex societies, no one could exist without it. it supports a lot of people, is a source of wealth, but has environmental effects and biological ones as a cost.
Hemoglobin S allele
allele of hemoglobin that turns normal, round red blood cells into abnormally curved (sickle) shapes.
What is evolutionary psychology?
an approach that examines psychological traits such as memory, perception, and language from a modern evolutionary perspective to identify which human psychological traits are the functional products of natural selection or sexual selection.
Biased Cultural Transmission
an individual copies a particular behavior or a particular "teacher" for a reason (showing some "bias").
What insights can ancient DNA provide?
analyzing ancient DNA allows one to directly test hypotheses that are based on theory from "modern" DNA studies through the ability to precisely date the age of remains that exhibit genetic types of interest
Neocortex
area of the brain associated with problem solving and behavioral flexibility.
Agricultural Food System
artificial selection plays a huge role, grow, tend to, manufacture, and process food. sedentarism
Monkey with downward facing nostrils, where are you? a. madagascar b. asia c. south america d. australia
asia
Why is altruism seemingly at odds with NS?
because it is costly to the individual doing the altruistic act and looks as if there is no benefit. Opposite of
Mutation is the source of all new variation. Explain how mutation can maintain deleterious alleles at low levels.
because often there will be people who may not have the deleterious gene but can be carriers for it. also the trait may have some kind of benefit like malaria and sickle cell anemia. mutation introduces deleterious alleles while selection removes them.
Why is it interesting when humans vary in some trait, such as ability to roll one's tongue, ability to taste PTC, or if they are sun sneezers?
because somewhere along the line, those traits were beneficial to that group of descendents, where it wasn't so much to others
How can one explain the maintenance of the hemoglobin S allele at levels exceeding 15% in some population in Africa and India?
because there is an advantage to heterozygotes. they are protected against malaria and they are more likely to survive than homozygotes of either type. So, variation in genetic composition of pop will be maintained.
Why are there thought to exist human universals in behavior?
because we may have evolved some universal mode of behavior when we were all living in Africa and this has followed us ever since
Why is DNA particularly suited to be the chemical basis of life?
because: 1. it is a very stable molecule meaning it is not easily prone to degeneration. also because it can deliver a nearly infinite variety of "messages" without many mistakes in the replication process. 2. it is a long molecule 3. it replicates itself and does a great job at it!
nothing in ______ makes sense, except in the light of ________
biology, evolution
hominid
bipedal ape
name two derived traits exhibited by hominids relative to other primates
bipedalism angled femur
What are some sources of ancient DNA?
bones, teeth and mummified tissue poo, quids(chewed on and spit out), midden (ancient garbage), permafrost (frozen soil)
name two symplesiomorphies exhibited by seal and whales
both comprised of cells, both have eyes
List evidence against the social hypotheses of primate cognition
but small-brained animals construct cognitive maps, navigate long distances and forage efficiently.
a theory of mind includes the ability to: a. understand how the brain functions, especially the neocortex b. to distinguish kind from non-kin c. to understand the mental states of other individuals
c. to understand the mental states of other individuals
humans have a nearly insatiable appetite for sugar, fat, and salt because: a. mcdonald's commercials are really awesome b. these appetites are always adaptive c. we are out of equilibrium with the modern world d. B and C
c. we are out of equilibrium with the modern world
Corn
central america
Tomato
central america
How do population geneticists define evolution?
change in allelic frequencies over time.
Derived Trait
characteristic present in a descendant taxon that was either: 1. uniquely derived (autapomorphy) 2. present in a recent ancestor and other descendants (synapomorphy) (examples: a decrease in body hair in humans versus primates, or flippers in whales when compared to terrestrial mammals) ... remember, this is a relative term!
Primitive trait
characteristic which has been inherited from a distant ancestor
mitochondrial DNA
circular molecule of 16569 base pairs in length
How did the adoption of complex foraging shift the evolutionary trajectory of bigger brains and slower development?
complex foraging requires subtle knowledge. Resources vary across sites, so skills must be learned and the time needed to do this favors a long period of learning. And the need to master complex skills favors a larger brain.
Describe the different forms of biased cultural transmission.
content bias: do what requires least effort to learn. Adopt the trait that is the easiest for you to understand and do on your own. This is being lazy and not thinking through things on your own results bias: do what provides the best result for you. prestige bias: do what famous or prestigious people do. Don't know why they are prestigious, but if you copy them you might become like them conformist bias: do what the majority of people do. anti-conformist bias: copy something very rare, so as to stand out.
Social hypotheses about the evolution of intelligence include: a. the exploitation of extractive foods b. the exploitation of other species c. the exploitation of members of one's group d. all of the above e. none of the above
d. all of the above
characters are more likely to exhibit continuous variation when: a. there are no environmental effects b. they are affected by alleles at only one locus c. inheritance is blending rather than particulate d. they are affected by many genes e. none of the above
d. they are affected by many genes
Fact
data in which conclusions can be drawn, facts are observations.
What is ancient DNA?
defined broadly as the retrieval of DNA sequences from museum specimens, archaeological finds, fossil remains, and other unusual sources of DNA
Describe the Neanderthals post-cranial features.
dense bones, short, stocky, powerfully built, wide fingers, powerful grip, overall a bit wider...adaptions to cold climate to increase heat retention and decrease heat loss.
Describe Homo heidelbergensis.
derived features: brain size 1200-1300cc ancestral features: large brow ridges, large prognathic face, no chin, robust bodies 300kya they made flake tools: large, symmetrical flakes from off core, edges were retouched. this is Levallois technique (mode 3)
What are some applications of ancient DNA? [Note that we discussed more than the examples used in this lecture]
diet and environmental reconstruction study the genetics of extinct populations and/or species determine evolutionary relationships study ancient diseases - e.g. the black plague test for population continuity vs. replacement molecular sex determination domestication of plants and animals measure the rate of molecular evolution
autapomorphy
distinctive anatomical feature, known as a derived trait, that is unique to a given terminal group. That is, it is found only in one member of a clade, but not found in any others or outgroup taxa, not even those most closely related to the group (which may be a species, family or in general any clade).
the central dogma occurs in what direction?
dna --> rna --> protein
What was the first domestic animal? What were other early animal domesticates?
dogs, sheep cows pigs horses
Pastoralism
domesticated animals that you have with you. you control breeding, feeding, and protection for the most part
a good example of a vestigial trait is: a. the fused radius and ulna of a mammoth b. the human brain c. the eye spots on a moth d. the homologous forearm structures of the bat and whale e. the whale pelvis
e. the whale pelvis
in the environments in which primates live, mature leaves are: a. available almost year-round b. high in calories relative to fruit c. high in fiber d. high in protein compared to young leaves e. both a and c
e. they are available almost all year and they are high in fiber
Why is it hard to both love your iPod and fundamentally disagree with evolutionary theory?
evolution works for the ipod as well as it does biologic organisms, over the years ipods have had a series of small beneficial changes, making them what they are today.
Explain the "Central Dogma".
explanation of the flow of genetic information in a biological system. dna makes rna protein, but not the reverse flow of information from rna to dna...in other words....dna replication, to transcription, to translation.
List evidence for the social hypotheses of primate cognition
extent of frugivory related to brain size and relationship with extractive foraging.
true or false, group living is always beneficial to primates
false
true or false, potassium/argon dating is used to directly date fossil remains
false
Female counter-strategies against infanticide
females try to confuse males of paternity - develop relations with protective mates
Describe the general trajectory that humans followed after leaving Africa.
first dispersed within africa, then mostly east, then more north and finally crossed over into north america and from there traveled south. then hit islands like polynesia (3kya) and finally madagascar (2kya)
Extractive foods
foods that are hard to process such as nuts, coconuts, durians, and ones that are hard to access like larvae (aye-aye and larvae, chimps use stick to get termites)
a creature that eats mostly fruit
frugivore
Frugivores
fruit
Why are primates good candidates for reciprocal altruism?
good because: stable social groups, good memories, flexible behavior.
what creates the best casts?
hard tissues create best casts
Michael Behe
he was a researcher that works for the Discovery Institute. He was one of the researchers that stated that intelligent design was a true scientific theory
Hunting and Gathering (Foraging)
highly mobile small groups of people who gain nutrients through hunting wild animals and collecting naturally occurring plants and roots
In what aspects of life history do humans differ compared to the other hominoids?
hominoids: slow growth, late reproductive age, high paternal investment, fewer offspring per individ., but higher survival humans: short period of lactation BUT longer period of childhood dependency, adolescent growth spurt, menopause, longer lifespan
molds
imprint/cast that is later filled in with minerals
Contrast individual learning vs social learning.
individual learning - behavior acquired through trial and error (expensive and dangerous) social learning - a behavior acquired by observing or interacting with another individual (social learners do not pay a cost for acquiring the behavior)
Explain the role of early inventions on evolutionary thinking?
inventions like the telescope, microscope, and barometer allowed humans to see things they couldn't before...like things really far away, or really small things. this allowed people to observe new sets of data presented to them and find a way to explain the discovery of these new phenomena.
cladistics
is an approach to biological classification in which items are grouped together based on whether or not they have one or more shared unique characteristics that come from the group's last common ancestor and are not present in more distant ancestors. Therefore, members of the same group are thought to share a common history and are considered to be more closely related.
Phenetics
is an attempt to classify organisms based on their similarities
phenetics
is an attempt to classify organisms based on their similarities.
Why is the term monkey misleading when describing old and new world monkeys?
it is confusing due to the nested hierarchies. all apes are monkeys, but not all monkeys are apes. Just as all humans are apes, but not all apes are human.
What does ancient DNA evidence tell us about the domestication of the turkey in the Americas?
it was domesticated in the south west.
Polygamy
multi-mate
Describe the characteristics of Homo erectus. Where did this species live?
large, robust bodies long legs and short arms slower growth rate reduced sex. dimorph. primitive: receding forehead, no chin, post-orbital constriction(occipital torus) shared-derived: smaller, less protruding face, higher skull, smaller teeth unique-derived: occipital torus, large brow ridges lived in Africa/middle east
Describe the characteristics of Homo ergaster. Where did this species live?
large, robust bodies, long legs and short arms, slower growth rate, reduced sexual dimorphism, live in E. Africa, and S. Africa, about 1.8mya
the term that refers to the concept that things found deeper under the earth's surface are older than the ones found closer to the surface
law of superposition
Foliovores
leaves
Crural index
length of tibia/length of femur X100
How might a long juvenile period favor a longer life span?
longer juvenile periods increase generation time. This will only be favored if there is a sufficient payoff, so this payoff may be the extension of human life span.
monkey with bilophodont molars, where are you? a. madagascar b. antarctica c. south america d. mainland africa
mainland africa
What are strategies that males take when living in pair-bonded groups? Why?
males invest in offspring, carry infants, share food with them, guard them, and are closely bonded to mates. This ensures the male will always have someone to mate with
Industrialized Agriculture
mass produced food resources. Can support the largest populations
reduction of chromosome number occurs during....
meiosis
Cognitive Map
mental representation of location, availability and quality of things in the environment.
What is the main difference between the processes of mitosis and meiosis?
mitosis: cell division and reproduction, diploid parent to 2 identical, diploid daughter cells, genetically identical cells, one division, creates everything other than sex cells. meiosis: sex cell division, number of chromosomes reproduced by half, separate homologous chromosomes, creates 4 haploid cells, crossing over occurs, sex cells only.
What kind of tools did Homo ergaster/erectus use?
more complicated stone toolkit, but still used olduwan. controlled fire. relied more on hunting. 1.8 mya H. ergaster associated with Oldowan (Mode 1) tools, about 1.6 mya bifaces added (hand axe, pick, cleaver) = Acheulian (mode 2)
explain how a simple mutation couldn't lead to human language
mutations almost never give the possessor superhuman powers (or in this case, modern human behavior and speech), mutations are coding errors and the rates are very low, complex adaptation occurs via small steps (the eye)
Explain why correlated character can result in a constraint on adapatation
natural selection does not always come to the best outcome and correlations can arise when one gene affects multiple traits (pleiotropy). When traits are correlated, selection on one trait affects another because the traits are link. By selecting for one, you automatically select for the other.in terms of beak depth of Darwin's finches, during the drought, seeds became larger therefore deeper beaks were selected for. This resulted in a positive correlation for beak depth, and .because of this it is not possible for a bird to have a deep beak and a wide beak, even though it is the best outcome.
name one convergent trait exhibited both by seals and whales
no hind legs, tail instead for swimming
How many calories does it take to raise a child to the point of being independent?
on average 13 billion calories
Tibia
on the inside
Fibula
on the outside
Polyandry
one female, multiple males
Polygyny
one male, multi-female
Monogany
one mate
Faunivores
other animals
In lecture, Prof Kemp talked about using DNA to tell which two of three population are most closely related. If you had this knowledge what might you also expect to be true of the two most closely related populations? Can you think of exceptions?
populations grew quickly or went under a bottleneck effect
Life History Theory
posits that the schedule and duration of key events in an organism's lifetime are shaped by natural selection to produce the largest possible number of surviving offspring
Benefit
possible reward for paying a cost (like searching for food during a scavenging season)
Competing hypotheses about origins of modern behavior
product of sudden change (human revolution): - development of language and symbolic capacities - mutation? product of gradual change - behavior in africa changed slowly over last 250ky - modern humans from Africa rapidly replaced existing hominid pops in Old World conventional view is that LSA people made better tools, hunter bigger animals and were more sophisticated. But, MSA people used Mode 4 tech too, hafted them to handles, and exploited fish and seasonal resources. They were able to survive in more challenging habitats and this is evidence of cognitive sophistication and social complexity. data from LSA and MSA suggest human behavior gradually became more complex in Africa, no abrupt change/cognitive revolution, this is an illusion that is caused by sampling error (10 sites in E. Africa vs. 100 sites in SW France)
Define the terms of Hamilton's Rule.
r = genetic relatedness of the actor, b = benefit gained by the recipient of the altruistic act, c = the reproductive cost to the individual performing the act
Hemoglobin
red protein responsible for transporting oxygen in the blood of vertebrates
Balanced Polymorphism
refers to a number of selective processes by which multiple alleles are actively maintained in the gene pool of a population at frequencies above that of gene mutation
What is the Environment of Evolutionary Adaptedness?
refers to the statistical composite of selection pressures that occurred during an adaptation's period of evolution responsible for producing the adaptation
Intrasexual selection
selection favors traits that make individuals more successful in same-sex competition (like how male-male leads to sexual dimorphism.
People: Tammy Kitzmiller
she was one of the parents that filed the lawsuit against the school teaching the intelligent design theory
Why did researchers first try to isolate mitochondrial DNA from Neandertals (vs. Y-chromosomal DNA or other nuclear DNA)?
similar properties but it is different by there is only one copy per cell, very difficult to extract. But, the dates will differ but all of the deepest branches in Y chrome tree are in Africa. Males have more variance in reproductive success
What's up with Homo floresiensis?
small body (3ft), small brain, small teeth, strong brow ridges, 35-14kya, lived at same time as modern humans. probably evolved from H. erectus, likely underwent the process of "insular dwarfing" common among animals living on small isolated islands, or a human with a genetic development abnormality and not an entirely different species.
What characteristics of mitochondrial DNA make it an ideal genetic marker to study?
small circular molecule (16,569 base pairs in length) non-coding hyper variable region weak selection high copy number no recombination
What are the physical characteristics of the first members of our species?
small face, Protruding chin, High forehead, Small brow ridges Small teeth Rounded back of skull Less robust than Neanderthals Longer limbs, slighter bones
Explain the key tradeoff in energy allocation.
somatic effort (growth, development) vs. reproductive effort (mating, parenting, nepotistic)
Explain how the sources of variation within and among groups can be different.
some is due to simple genetic differences. because evolution will favor whatever trait is best for the environment that the individual is from. for example, being tall and skinny will not be favored where it is coldand dry within: mutation and frequency dependent selection (balance polymorphism). mutation generates random variation and many genetic diseases are caused by mutations frequency dependent selection: among groups: natural selection and genetic drift NS: in different environments may favor different traits, gene flow will tend to homogenize populations, if selection is strong enough genetic variation will be maintained, NS may contribute to some genetic variation among human groups
Potato
south America
Monkey with three premolars, where are you? a. madagascar b. japan c. south america d. mainland africa
south america
Chicken
southeast asia
What might the level of sexual dimorphism in australopithecines indicate about their system and/or social structure?
suggest mating structure was one male, multi-female groups or polygamous. Strong male-male competition
Global Optimum
the best solution to a problem out of all the possible solutions.
Local Optimum
the best solution to a problem when compared to all other solutions immediately surrounding it. but not the BEST solution of all.
Nucleotide
the building blocks of DNA and RNA, comprised of a sugar, a phosphate group and one of the four nitrogen bases
genotypic frequency
the frequency in which a physical trait is expressed
allelic frequency
the frequency of an allele appearance in a population
What's the deal with lemmings?
the lemmings are rodents where many people believed would commit mass suicide when their population got too big. But in reality, the movie makes herded them off cliffs, and put them on a turntable that would make the lemmings dizzy, then run around and fall off cliffs
Menarche
the onset of a girl's first menstrual period
How does meiosis explain the observations made by Mendel?
the segregation of chromosomes in meiosis shows that each parent gives one allele for each trait at random to their offspring....despite whether the allele is expressed or not. after meiosis, the result is 4 haploid daughter cells, each genetically different from the parent cells and each other. This is why Mendel saw so many outcomes in his experiments in pea plants...meiosis assure genetic diversity in sexual reproduction. This shows that genes for different traits are inherited independently of one another.
Systematics
the study and classification of living organisms to determine their evolutionary relationships with one another.
Explain how primates keep track of group membership
they recognize others as individuals - they know members of their own group - respond aggressively to strangers - know ranges of neighboring groups monkeys seem to know a lot about their own relationships
In the 19th century there was a prevailing notion that the traits of offspring always represented an average of those exhibited by their parents. What type of inheritance is this known as? Explain why evolution by means of natural selection could not proceed if this is how inheritance truly works.
this is known as the blending hypothesis or blending inheritance. The problem with this is that it removes variance, therefore evolution by means of natural selection could not proceed if this is how inheritance truly worked.
William Farabee
traced the occurrence of bracydactyly through multiple generations of a large family in Pennsylvania who had short fingers. He found that its pattern of inheritance followed one of an autosomal dominant trait.
Gummivores
tree gum
Archbishop James Ussher
used scholarly records, the bible and other sources, to date the age of the earth, he dated creation at 4004 b.c.
Explain the role of disgust from an evolutionary perspective.
was an early form of germ detection. gross things are bad for our health. hypothesis: disgust is an adaptation to prevent disease. Universals: 1. Bodily excretions and body parts 2. Decay and spoiled food 3. Particular living creatures 4. Certain categories of "other people" 5. Violations of morality or social norms*
Artificial Selection
we pick and choose the traits being passed on
True-breeding line
when 2 parents of identical genotypes (AA x AA) produce a child with an identical genotype.
Contest competition
when one consistently defeat another, winner & loser → dominance hierarchy → value of allies, female relationships, dispersal patterns. - get resources completely or not at all. Need stable resources
Sexual selection-selection
when strength of NS on males and females differs
How can plant and animal domestication be discerned from the archaeological record?
you can find such evidence coprolites and in animal fossils that show geographic location, size sexual characteristics osteological changes.
