Primate Taxonomy and Evolution: An Overview of Different Groups and Characteristics - Prof, Study notes of Introduction to Cultural Anthropology

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Primates September 30th, 2013  Non human primates are very intelligent  We give them human tests and they do very well on it  Ex- they gave the test to college freshman and to chimps and there wasn’t that big of difference in the end scores
o Gorillas get a bad wrap for being big and fierce and mean  Gorillas diet is 99% vegetarian; and the 1% that isn’t vegetarian is insects  They are actually gentle but fierce when they sense threat o Chimpanzees are actually very fierce and very aggressive and strong o Nonhuman primates are more than just monkeys, they are highly variable o The way non human primates are categorized in 4 different groups:  They correspond to taxonomic classifications Different Kinds of Primates (THEY DO CORRESPOND TO THE TAXANOMIC CATEGORIES)  Prosimians - Zaboomafoo  New World Monkeys- only found in North and South America  Marmosets- can have twins  Old World Monkeys  Live in Asia, Africa, South Pacific  Apes  Do not have tails  Tend to be bigger than monkeys  Orangutans; Gorillas  Chimpanzees- NOT A MONKEY  Very aggressive  NOT monkeys- they are apes Proposed Changes to Primate Taxonomy  Brachiation-swinging with arms  Bipedalism- walking with two limbs to move; humans are obligate bipedial Senses and Brain o Increased reliance on vision.  Ex- anterioly facing eye orbit  Generally includes color vision, depth perception(see in 3-d), and that eye sockets are located on the anterior portion of the skull o Decreased reliance on smell. Manifested in a reduced snout. Apparently, dogs smell better than humans do. Humans have less olfactory senses. o Encephalized – primates have larger brains relative to the size of our body. We have a large complex brain—correlated to a higher intelligence. Maturation, Learning and Behavior o K-selected vs R-seleceted –- deals with maturation and gestation  K- selected - one offspring at a time(few offspring) and are born immature with a need for parental care. Tend to have al long maturation period. Longer gestation (pregnancy) and longer lifespan.  Ex; humans and most primates  R – selected – Have many offspring at home time(hundreds) and they are born mature;Born able to take care of themselves. Shorter lifespan.  Ex:Insects, fish, and spiders. o Arboreal vs. terrestrial  Arboreal- living in the trees; most primates make their living in the trees  Terrestrial- living on the ground; some of the larger primates have a terrestrial component o Diurnal vs nocturnal  Diurnal- active during the day; most primates  Nocturnal- active at night o Flexible, learned behavior o Social Arboreal Hypothesis- this suite of characteristics that we just talked about- the reason why they have this group of characteristics is because of the adaption of an arboreal environment o Dental Characteristics  Heterodonts- means different teeth o Incisor- biting  Located in front  Maxilla is the upper jaw  Mandible- lower jaw o Canine- ripping and tearing; the big teeth  Front/side of jaw o Premolar- grinding  Located along the sides o Molar- grinding and chewing  Located along the sides o Diastema- a space between the teeth  Associated with the placement of canines o Sectorial P3- first mandibular premolar  Differently shaped; elongated crown; tear-drop shaped; enlarged posterior cusp; slanted; sharpened  Dental Formulas – tells you the number of teeth in one half of the mouth and the sequence in which you find them o NWM (New world monkeys): o 2.1.3.3.  maxilla  2.1.3.3.  mandible  - it’s the number of teeth in ½ of the mouth o The number and the type of teeth in one half of the mouth o 2’s- number of incisors in one half of the jaw on maxilla or mandible o 1- number of canines in one half of the jaw on maxilla or mandible o 3- number of premolars in one half of the mouth o 3- number of molars o OWM/Apes/Humans  2.1.2.3.  2.1.2.3.  2 incisors  1 canine  2 premolars  3 molars  we have fewer premolars in the upper jaw and lower jaw o Primate Terms-  Sexual Dimorphisms- difference between the size, the color, and the shape between the sexes of a species o Di- two o Morph- shapes o Means differences for males and females in any characteristic within the same species  Color- peacock vs. peahen  Size and shape- male and female OWM  Male gorilla a lot larger than females -there can be behavioral inferences that can be drawn o o Primates o Before it was found out the chimps in the wild would manipulate objects for a specific purpose, we thought it was just humans and that we were the higher being. It was a big deal. o HAVE Post-orbital bar- the lateral edge/border of the eye orbit; instead of having a fully/completely enclosed eye orbit. o Significance: in some mammals, the eye orbits do not have complete rim, there is no bone there. o Procimians DO HAVE completely closed eye sockets. The postorbital bar is the lateral portion. That distinguishes them from other mammals. They also do NOT have a back through eye orbit. There is no postorbital plate. o Dental comb- a specialization in the teeth, specifically referring to the incisors, the mandibular incisors. Special because they are all very narrow and project anteriorly (to the front).;;used for grooming and eating They don’t stick up. Dental comb is projecting forward, used to eat and for grooming. Only some Prosimians have this. No monkeys or apes will have it. And if they do they Prosimians. o Grooming claw- o used for feeding and grooming. 2nd or the 3rd digit. Middle finger is different from others, elongated and narrow specialized digit, usually in the hands, used for feeding specialization. Some have it some don’t, no monkeys or apes will have it. Only some Prosimians (comparison questions monkeys, apes vs. prosimians on test.
Anything that has a grooming claw/ dental comb are prosimians o All Prosimians are old world- Southeast Asia and Africa. o 4 Examples of Prosimians: o Lemurs- 2 kinds to know  mouse lemur and sifaka (ON TEST: matching section, match examples of primates to specific groups, is it Procimian, new world, old world, ape? You will match lemurs to Procimians)  Lemurs found only on island of Madagascar. If I give someone my notes and your not here FUCK you this class sucks cock. Little competition from other primates and mammals, they diversified and expanded. Diversity in their size like mouse lemur and sifaka. Sad that once people got to Madagascar, they began hunting them. Now one of the most endangered primates is Prosimians. Mouse lemur; Sifaka lemur o Lorises- 2 kinds to know o also Prosimians- Old world (all Prosimians are old world- not well studied. 2 examples are bush baby and slow Loris. o (Matching on test: a prosimians, new & old and apes also none of the above ) examples to be matched  Bush baby: got its name due to its vocalization: baby crying  slow loris  Don’t know a lot about them. Tend to be nocturnal, slow climbers. Ranging sizes. Very small 6 inches to 2 ft. Because they are nocturnal, they have to keep still from predators.  Wrist bones and ankle bones are specialized that allow them to stay still for hours. Keep still so predators won’t get them.  Vocalizations. – use them to recognize each other; Sounds that they make. Primates do use vocalizations in specific ways. Among lorises- each species uses vocalizations in a specific way. Will use vocalization more than vision or sense of smell.  Tend to be more solitary creatures.  They are primates so they do have social behavior.  (Know the 4 examples of Prosimians- vocalization and specialized wrist and ankle bones to stay still- Lorises. Lemurs- know their geography, endangered) o Tarsiers- (not on matching)considered Prosimians- their taxonomic species is considered to be in transitions some classified as monkeys and apes; molecularly they are more similar to monkeys and apes.  Blend of Characteristics: 4-6 ounces, average. Very tiny, smallest of all primates. Nocturnal insectivores, leap around up to 3 meters, can rotate head almost 180 degrees, found mainly in south pacific. Indonesia and Islands of South Pacific (Philippines) are natural habitat, also endangered. Taxonomy is in transition because molecularly, they are more similar to anthropoids. o They are in transition because they resemble Prosimians but molecularly they resemble apes  o Hint for test- making comparisons and contrast o Prosimians  Small bodied o Examples:  Buffy headed marmoset  Golden Lion tamarins  Only group that have social organization of polyandry-  Polyandry – one mature female for getting slammed. Other males and children. Other women don’t breed  Means that in social organization they are organized into small groups, in small groups they only have one mature breeding female. Then they have other adult males and any dependent offspring. There are other females present that are not children or infants. They are not breeders, have to do with hormones that mature breeding females emits. The other females don’t breed.  NWM Callitrichids are the only monkeys that do this in primates. Type of polyandry, very unusual.  Also tend to have twins . Not common among non- human primates. o NWM: Cebids o Examples:  White Throated Capuchin  Howler monkeys  Cebids have good manual extremely dexterity (able to manipulate things easily); good for entertaining humans, and service monkeys like entertaining us and shit for example:  Organ gridding monkey- would be a Cebid, intelligent. White throated is often trained in movies.  Howler monkeys- get names from vocalization, uses vocalization in specific way, use to find each other and use to mark territories. o Summary for test  Prosimians: General information, 4 examples (probs in matching section)  Specific: Lemur (and their geography);;; Loris (vocalization)  NWM: General information, 4 examples  Specific: Callitrichids (polyandry social organization, twin births) Cebids (dexterity, vocalization) o o 10/7/11 o Old World Monkeys (OWM)- o 3rd group, closer to apes in their characteristics. o “Catarrhines”- contrast with plattyrines- the info order of new world monkeys o Catarrhines- the info-order of old world monkeys but does include apes. o Infraorder Catarrhini includes apes as well as OWM (unlikely to use the term Catarrhine on the test) o Some of their characterstics will overlap with apes o Characteristics of OWM (monkeys): o Very diverse group o Geography:Old world is referring to Africa and Southeast Asia. In terms of size, there is a lot of diversity in size. As small as 2 lbs large as 80lbs. o Body size: bigger than NWM but smaller than apes o Dental formula- 2123/2123 o Nasal region- tends to have a narrower septum. The shape of the nostrils tends to be oval or slited and they face downward or interiorly. (diff from NWM) o Tails: They are monkeys so they have tails. OWM have tails, some don’t have tails but the generalization is that they are monkeys so they are going to have tails. No OWM have prehensile tails. o Behavior and Locomotion: The smaller bodies are arboreal. Larger bodies spend more time on the ground(terrestrial), but they do have arboreal component to their behavior.;; also exhibit brachiation and quadripedalism o Ischial callosities - (straight definition on test) – Ischial- ishium, part of your hip bone. Callosities is referring to a callous, hardened area of skin. Hardened area of skin on the ishium (butt) . It is hairless, provides a nice seating pad for monkeys to sit. Monkeys sit up a lot. Provides a butt pad. o OWM- 2 diff groups o “Cheek Pouch Monkeys”  (Ceropithecinae)- reason they are called cheek pouch monkeys- have extra skin in face and neck where they can store food for some period of time(they have cheek pouches). Primarily fruit eaters. Can eat food quickly and store it. They can save it for later. Can be beneficial if you see a predator, move up into trees.  Mandrill and baboon- 2 examples of cheek pouch monkeys o “Leaf Eaters”-  (colobinae)-eat lots of leaves. Vegetation is primary food source. Have anatomical specializations in their stomach. Digest cellulose in plant cell walls easily. A lot of primates don’t have that. Also have a diff morphology to their teeth, teeth are bigger and sharper and can chew well. Don’t have cheek pouches.  Colobus and Proboscis monkey o Diff between two groups are their dietary specialization;  As far as the specific monkeys; you need to know mandrill is an owm- not that its cheek pouch monkey o Know the differences b/w OWM and NWM- easy and good exam questions. o o Apes- o the final grouping of primates. o o Very diverse o as adult male gorilla ages or become matured, hair on back turns grey. There is only one per group; Has grey hair on back. Matured gorillas. Gorillas have one adult male, silver back with multiple females and lots of offspring. Leader, protector, leader of troop. Once younger gorillas begin to reach maturity, they leave their birth group. Single male will form own group. Studied by Dian Fossey (check her name). Very endangered (only 600 left).  Chimpanzees- studied by Jane Goodall o We share large part of our DNA with them o Intelligent, aggressive, strong, big, 100lbs, very strong. 10x stronger than a human of the same size. Very smart, making tools, spears, aggressive.  Bonobos- o Used to be called pigme chimps- misnomer, separate species. Tend to be more slender. They are also very smart, share lots of our DNA with them. o Known for promiscuity . They are less aggressive and they use sex for everything. Always having sex. Not just for reproduction- do it to increase social status, diffuse tension (big group sex), stress relief, use it for food sharing. Affection. Do it face to face, unusual for primates. “any friend in the bonobo world is a friend with benefits” o Very intelligent but have not been observed making spears but can make tools. Have cognitive ability of chimpanzes. Less aggressive and tense than chimps cuz of all da sexxxxx. o Summary:  OWM: general info, examples  Specific: “Cheek Pouch” vs. Leaf eaters”;;dietary  Apes: General information(distinguish from monkeys), Examples  Specific: Lesser Apes (brachiators, vocalization) o Great apes (mainly on silver back, social behaviors) o o o Endangered Primates: the Bad News o Statisticts-  2000 miss Waldron’s Red Colobus (OWM) declared extinct Horton Plains Slender Loris: 4 sightings since 1937  Researchers estimate only 320 wild mountain gorillas  Golden Lion: Tamarin: more alive in captivity than wild  63% of all primates are endangered. o Endangered Primates  People: people fucking suck.  habitat destruction o forests are rapidly disappearing. Logging, faming, shit like that.  hunting- not for fun, sport, legitimate uses of hunting for food. Other countries eat primates. Or for medicinal purposes.  Trade o pets or service animals o for export and trade, estimates 30,000 animals caught and sold a year. Illegal trade is second only to drugs, whole or parts of animals being traded.  pets/service animals- not suitable pets o they are not domesticated; you have to go to extreme measures to keep them- they cut off their fingers and pull all there teeth out o mental and physical health: they are subject to depression and anxiety; physically- we can exchange diseases (HIV) o monkey’s and Hiv??- monkey’s can get human diseases and humans can get monkey diseases. Documented diabetes in pets. Captive animas, gorillas- documenting heart disease. o Positive associating with keeping primates as pets. Helping hands - helps them with paraplegics ;provides a monkey for a disabled person.  still have black mark of having monkey’s altered by removing teeth, thumbs- precaution for protection against wild animal, borderline animal cruelty??? o Hope?  Yes. Pygmy tarsier observed for the first time in 80 years.  Nine primates downgraded from critically endangered.  Conservation efforts-  Education/Awareness o ecotourism- Socially and ecologically aware tourism. Applies to all kinds of nature conservation efforts- tourism as a way to support conservation efforts; money that is made goes to conservation efforts; they minimize the impact of the activity on the environment  Ex: gorilla tour- pay a lot of money to spot wild gorilla; money that is made goes to enforcing antipoaching laws etc. o Legalization-  Laws about preserving a habitat; laws that establish hunting season; established protected areas where no one is allowed to hunt; laws that regulate international trade of primates o Dominance hierarchy o Dominance hierarchy is ultimately relationships, multiple relationships, relationships within a large group. Only social structures that don’t have a hierarchy is monogamy and solitary.  Establishes parameters- there is a pecking order; you have certain benefits to a high status; higher ranking individual can control a lower individual by just giving them a look;  Position not permanent- the position can fluctuate throughout the individuals life; your rank can be influenced by age, sex(males are typically the higher;; NOT ALL MALES RANK HIGHER THAN FEMALES), aggressiveness, intelligence, birth order, the mothers ranking  benefits  it reduces aggression and it reduces conflict in a group  literal- preferred access to food or water hole; sleeping sites; and even estrus females  When you have large groups of individuals you have to have understanding of place in the world. o High ranking individuals, lower ranking, everything in between. o In establishing hierarchy or ranking, it imposes order in the group. Establishes behavioral parameters. o Means higher-ranking individuals get certain privileges and everyone else knows it- less aggressiveness. Have preferred access to certain resources. Since everyone knows this- it reduces aggression.  What contributes to rank- age, sex, aggression (how aggressive you are), intelligence, mother’s social position, and birth order. o Rank is not permanent, lower members could rise up and challenge you, does change throughout an individual’s life. o In general, males tend to be dominant ranking sex, however, research showing that males and females have their own set hierarchy but are someone integrated. While males generally rank higher, some species have females ranking higher. o Need ranking to establish order among large group. Primate Behavior: o Aggressive behavior o Aggressive behavior- fighting, kicking, yelling, biting, staring, yawns- showing teeth. o Charging- particular behavior where animal rushes toward you.  Aggressive display, trying to intimidate. o o o When do we see aggressive behavior ?-  Competition over resources. (Dominance hierarchy does help to alleviate some of this)  Feeling threatened.  Defense of territories  **Home range- a broad geographic space that a group occupies; wont be defended. (Can be large, broad area that they are occupying). Home ranges can overlap- wont lead to aggressive behavior.  **Core area- a smaller more restricted space within the home range; area that to group likes and where they spend must of their time. A core area will be defended if other group tires to invade it. Core areas will be defended leading to aggressive behavior. o Affiliative Behavior- any behavior that promotes group relationships and cohesion(any type of friendly gestures).  Grooming- individuals pick through hair; it serves a hygienic purpose and its pleasurable  Altruism- ones behavior benefits someone else but there is a cost to yourself; helping another at individual risk of ones own safety;  Ex- unrelated adults helping infants; unrelated males protecting someone else  Found in: Poliginous and polyandris group, multi-male and female. In terms of safety and protecting, have unrelated individuals protecting young or getting food for them. Altruistic because they get no benefit from helping these individuals. Adoption of orphan infants is another example.  Cooperation- individuals helping each other to find food or when threatened; working together.- to get food, group hunting o Reproduction- sex  Previous Ideas: It was believed that females were very selective in their mates and they only mated with a few individuals; we thought that females were only receptive to mating only during estrus-  Estrus- a period of sexual receptivity in females that is correlated with ovulation and hormonal cycles; its very obvious its marked by swelling and color changes in the genital area  We know mating isn’t strictly tied to estrus; we know they are open to mating than was previously thought  Sociobiology myth- all females are chased and coy in receptive to sex and to only want to have sex only when they can conceive; this can lead to stereotypes  “Selective Promiscuity”- their sexual receptivity is not strictly tied to estrus and they’ll mate even if they can’t get pregnant; females will mate will mates who are friends with them so its often selective; they will mate with more than a few individuals in their life time but there generally is a selection(friend or someone who shares food with them)  type of food available  predators  these things influence the group behavior o Doesn’t exclude biological factorsWill take into account BMR, age, biological variables but it is emphasizing the role of the environment. o How might resource distribution affect group size?  Can look at predator behavior and how that affects altruistic behavior or cooperation in a group, could look at sleeping patterns. How nesting affects aggressive behaviors. Researchers want to know why certain behaviors are adaptive in a group for certain primates. o Ex: diet and social structure- insects may not support a very large group  If primary diet is leaves and you life in forest, folivorous, then food will be easy to get. If insects are primary resource, it will be scattered around. Not in one place, more difficult to find, have solitary social organization because they have to go on their own to look for food.  Lorises appear to solitary or very small groups  Baboons- have a large groups because they eat off of grass  What is this perspective talking about? How can environmental conditions impact behavior? Will it be adaptive or not? o Predator behavior, sleeping resources, nesting sites, how environmental impact could affect social behavior. o 2. Sociobiology- the study of the evolution of behavior that emphasizes the role of genes on behavior o Ultimately looking at a relationship b/w genes and behavior. o If they (behaviors) can be inherited they can be acted upon by natural selection. o We know that have not indentified a gene that is 100% responsible for behavior  Predisposition- there is a genetic component  When sequencing genomes, helping us understand how our body works. Can any behaviors that can be correlated to a specific gene.  They have not identified any one gene with one particular behavior.  ex: testosterone and aggression  there is a correlation between the increase in testosterone and aggression  testosterone is controlled by genes, has been linked to aggressive behavior. Primates, those who have high amounts behave more aggressively more often. Aggressive behavior related to higher fitness then can high testosterone lead to higher fitness? –then indirectly natural selection can operate Know difference b/w 2 perspectives, know some examples of research. Testosterone and aggression, diet and social structure. Behavior to differentiate sociobiology(internal) and behavioral ecology(environment) and know examples Language/Communication Do primates have a language? o Most would argue no. Language implies that there are rules for putting sounds together. ;language implies structure or organization; it also uses symbols o Primates communicate effectively  ex: vocalizations- sounds that they make; barks/shreaks/; bush babies(lorises) use vocalizations to recognize each other, more than sight or hearing.  ex: bush baby vocalization  ex: howler monkeys  ex: gibbons- use it to maintain family bonds and pair bonds  Gibbons and howler monkeys use it to mark territory.  Verbids- have diff vocalizations that they use according to predator threatening them. o posture—how the body is oriented in space can make a big difference; if they are crouching it can me fear but if they are standing and beating their chest could mean dominance; presenting —a lower member presents their hind is a gesture of submissiveness o facial expressions- a yawn in primates could indicate a threat(it displays the large canines)fear grin, aggression. o **displays- gorillas- throwing around leaves, stomping, threatening. o Autonomic responses- not voluntarily controlled that the body does. Fear and estrus can enhance hormones and communicate within a group. Hair standing up.  Ex- raised body hair(if it feels threated) or enhanced body odor (mostly associated with fear; or with pheromones when mating) o FOXP2 – a gene that is believed to be associated with language abilities. Humans in produces a protein that is different from all other mammals; Humans are different than nonhumans in there FOXP2 gene. Gene is linked in our ability to learn how to speak and to interpret what we hear and take action. Helps humans put sounds together to make words. Its more complex than just a language gene but its associated with language abilities and the fact that is different in primates could be contributing to why we have language abilities and they don’t o o Notes from movie Culture was long believed to be uniquely human. Culture shares learned behavior- ex: machine that chimps get grapes from. Culture o “learned Behavior” in a group of organisms; its passed down between generations; and its variable - seen in chimps o Analogy- a structure that is shared because of a common functional adaptation. this similarity developed because different organisms evolved in similar environments so their form developed similarly. When you have structures similar to each other based on a common functional adaptation. Doesn’t show evolutionary relationships or relatedness, just shows similarities and differences. Usually they have similar traits because they share a common environment.  result of convergent evolution; the wings of insects/reptiles/birds/bats; another example is body form of sharks and dolphins o KNOW DIFFERENCE AND EXAMPLES B/T HOM AND ANAL o Cladistics- a method of classifying organisms based on whether a homology has altered or stayed the same. Looking at the details of homologous traits. Breaks down homologies into more specific details:  Ancestral (primitive)- one that has not changed or altered from the ancestral condition; the same as the ancestral condition.  Toes- primates have opposable toe- believed to be an ancestral condition.  Think about modern humans, we do not have opposable toe, would be derived.  Modern chimps- opposable toe- ancestral  Derived (modified): one that has altered, changed, modified from the ancestral condition.  Examples: look at hand and horse leg  Earliest mammals are believed to have had 5 digits  The modern primates/humans still have 5 digits- we have the ancestral trait  In horses, they only have one finger(phalange); it is a derived trait because they only have 1 its different from the ancrestral  Another example; aposable toe  In ancestral primates its ancestral  Chimps still have an aposabe toe so its ancestral  In mondern humans the trait has changed we don’t have an aposable toe so it’s a derived traited  Cladogram- a way of displaying results from a cladistic analysis; a tree of relation- doesn’t necessarily display time component but it is showing you relatedness. Showing which groups are more related to others. o Ultimately trying to define a species  Biological Species concept- a group of organisms that can interbreed and produce viable offspring. That means their offspring can then reproduce within same group.  Not strong enough definition to encompass everything. Problems with Biological species concept:  1. Organisms labeled as different species but they regularly interbreed.  1. Organisms that are labeled as the same species but they never interbreed  2. Asexual reproduction.  3. How are you going to determine reproductive viability(sexual activity) from fossils- difficult,, impossible,  One of the greatest rivals of the biological species concept:  Phylogenetic species concept- a species is a group who shares common traits that are based on decent from a common ancestor; recognizes groups that share a common decent. Groups that share a common descent are recognized as the same species. A species is one who shares different traits based on common descent. Groups that share derived homologies are more likely to be a species.  Paleospecies- a species determined from the fossil record. No living counterparts.  Intraspecific vs. interpecific variation  intraspecific- variation within a species- can be accounted for by age differences and sexual dimorphism, based on geographical differences. o ex: skeleton of 2 year old, skeleton of adult.  Interspecific- variation between or among different species; cannot be accounted for by age or sex differences. They are true differences between groups.; more useful to determine between different groups o o Modes of Speciation o Speciation- the development of a new species o How do new species develop?  Processes that act on allele frequencies and thorugh time. Process that impact allele frequencies, genetic drift, gene flow. All of those processes interacting through time with the enviorment is how you end up with a new species.  When do you have enough change to constitute and new species?  Up to paleoanthropologists. Are differences great enough to warrant it a new species. No simpl answer. Speciation is simply the process of becoming a new species. o Cladogenesis- how do specieis develop?  Hypothesis based on geographical isolation  A mode of speciation where you start with a population or species. You start with a species and over time something happens that causes the population to separate. Usually a geographic isolation that occurs. Population gets separated slit, through time as each population is acted upon by natural selection, genetic drift, enviromentmetns dramatically different, populations will be come more distinct from each other.  in the natural world, its not either or, its both o Dating Methods o Allow you to place information in a temporal context. o Relative dating-arranging artifacts or fossils in a sequence without reference to an absolute age; use of artifacts and fossils to associate age with a site; dating methods used to determine the order of past events without necessarily determining an absolute age. Putting past events into a sequence. Fossil, artifact. o Two Examples:  1. Stratigraphy- the study of the earth’s layers, the earth’s surfaces. Based on greogrpahy. Based on Steno’s “Law of Superposition” - the deeper layers of earth are older than then shallow layers   Says that layers that are deeper in the earth are going to be older.  You can have intrustions(^youngest), stratigraphy can flip over, can be changed by natural events in the earth like earthquakes. So you can get a false intrusion. But in general, the deeper it is, the older its going to be.  2. Biostratigraphy or Fawnal Correlation- has nothing to do with earth’s surface.  Correlate your artifact or fossil to stage in the evolutionary sequence of a particular group of animals  Animal/fonal correlation- Biostratigrpahy uses the sequence of evolutionary change in animals to get a relative date or age of site, artifact, fossil.  Examples of animals- horse- o  so if you find pliohypus bones at your site then you can conclude your site is around 10 million years old; you use a known sequence of an element and attribute it to a certain date  using sequence of evolutionary change in animals to get an age for your site.  (need to knowthat was 2 examples of relative dating methods and how to apply them)  also be able to compare them to absolute o o Absolute (Chronometric) Dating-  Will give you an actual date  based on radiometric decay. You have isotopes of some elements that are not stable which means that they decay over time. The rate of decay follows the mathematical pattern called a half life. Because the half life is variable based on element, that will determine which method you will use to date your sight. Have various instruments they can use to measure decay isotope to stable isotope; then it can tell you how much time has passed since the two types were equal.  1. Carbon 14 (Radiocarbon)- All carbon is taken in by living organisms. All living organisms take in carbon, carbon 12- stable, carbon 14- unstable. Organisms taking carbons in at same rate so they are equal. When organism dies, carbon 12 remains stable and 14 decays. Carbon has a half life and its half life is relatively short with regard to geography. Significance? Because it is short, it make this method most useful for sites that are relatively recent. o Know its an absolute dating method o Because carbon has a relatively short half life, so that means radio carbon can only be used to date relative recent sites  The site has to be 70,000 years old o samples- any type of bone, wood, charcoal, shell, natural plant fibers, living organisms use carbon to make shells. (anything that was once alive)  2. Potassium/Argon (K/Ar) (Radiopotassium) o know that there are absolute dating methods, not just relative. Know what the implactions of half lives are, short half life, good for recent cites o because the halflife is so long, this method is only useful for old sites; potassium argon- good for old sites o samples- igneous rocks o o Mesozoic- age of dinosaurs. Another mass extinction at the end of mezozoic in the cretaceous- took out dinosoars o o Cenozoic- age of mammals, species left alive diversified and expanded, primarily mammals. 4 QUESTIONS FROM HERE DOWN -EACH QUESTION FROM ONE OF THE EPOCHS -THE DATE WILL NOT BE THE QUESTION o Primate Evolution  Paleocene (65-55 mya) o Earliest EPOCH o Have found a group that may be ancestral to primates: o Not really any good examples of anything like primates, BUT the o Plesiadapiforms  Small arboreal quadrupeds  Did not have opposable big toe  Relatively small brain  Relatively long, narrow snouts  Lateral facing eyes with no post-orbital bar  Had claws instead of nails  Small arboreal quadrupeds that are possibly the ancestral group for primates  Could be placed in an order called “Proprimates”  Proposed order for the Paleocene critters  Could be either ancestral to primates or they are related to the ancestors of primates  Eocene (55-37 mya) o First definite primates(1 st identifiable primates) o Have the clear primate characteristics  Slightly larger brain  Forward(anterior) facing eyes  Post orbital bar  Opposable toes  Nails  Slightly reduced snout o “Euprimates” –proposed order for these critters o *Examples*  1.Adapids  2.Omomyids  Both are believed to be small bodied  More Prosimian like o “Basal Anthropoids”  Paleospecies that are more monkey like  Oligocene (37-22.5) o We start to see different examples of “monkeys” o More anthropoids (refers mainly to monkeys) o Greater degree of enceph o Reduction in snout o Individuals with tails Two examples: o Apidium (genus)  Look like little monkeys  Enclosed eye orbit  Encephalized brain  Found in Egypt  Small bodied  Quadrupeds  Definitely primates o Aegyptopithecus (genus)  Slightly larger than Apidium  quadripeds  Big brain  Enclosed eye orbit  Had pretty bug snout  Large canines  OWM dental formula o KNOW THAT DURING THIS PERIOD WE START TO SEE TRUE MONKEYS AND THE TWO EXAMPLES  Miocene (22.5-5 mya) o “Golden Age of Hominoids”  Hominoids is referring to Apes  during this EPOCH you see an explosion of diversification of hominoids (apes) o African forms  Proconsul  Relatively small bodied ape  Ape like skull  Ape like dental formula  Quardripedal but not knuckle walkers, weren’t very good brachiators  Relatively brasile- muscle attachments weren’t that big  Shortened forelimbs relative to hind legs- more monkey like on everything post skull  Monkey-like skeleton o European forms  Dryopithecus  Medium Sized bodied  Do have the adaptation for brachiation  Lots of variation in European forms  Ape like cranium  Post cranial skeletons are more ape like  Some skeletal features that show they were good brachiators  Found in France and Spain o Asian forms  Sivapithecus  Medium to larger sized  Found in Pakistan o · Sexual dimorphism: differences between males and females of the same species o a. Example: peacocks and peahens o b. Can refer to color, shape differences or size o · KNOW THE APE DENTAL FORMULA. 2.1.3.3. and the difference between apes and humans is our premolar. o o Review session 10/26/11- 7:30- BRING SMALL SCANTRON!!! o o Primate Evolution- o · Paleocene (65-55mya) (THE OLDEST PART OF THE CENOZOIC) (question on test will not come from dates) o o During Paleocene there aren’t really any easily distinguishable primates. o § Plesiadapiforms- may have been a primate ancestor? Don’t really fit the characteristics we learned of primates. o ú Do represent the closest thing to a primate that is available. o ú Plesiadapiform- Small arboreal quadrupeds that represent a possible ancestor to primates. Good candidate for an ancestral primate. Represents the oldest possible relationship to primates. o · Eocene- have the first definite primates (55-37mya) o o “Euprimates” o § adapids o § Omomyids o ú Both are different genus names that have been given to Eocene primates. o § Fossils actually resemble primates. o ú slightly more encephlaized, eye orbit, more forward facing eyes, some have reduced snout. Have nails instead of claws. o § **remember three words above. Euprimates, real primates, first real primates date back to the Eocene. o · Oligocene (37-22.5) o o “Anthropoids”- you def have anthropids. o § think about monkey’s when talking about anthropids. o § more species that resemble modern day monkeys. o § mostly found in Egypt and Africa, some found in south amperica. o § Apidium- reduced jaw, post orbital bar, maintain definite primate characteristics. Has the NWM dental formula, 2133 but apidium is found in Africa. Primates in Africa with NWM characteristic. o § Aegyptopithecus- also a genus name like apidium o ú larger bodied monkey, primate characteristics, much more encheplalized with larger brain, size of modern howler monkey- small to mediuim size, quadrapedal. o § Shows variation in the oligoccene. o · Miocene (22.5-5mya): “Golden Age of hominoids” o o Hominoids- referring to apes. Lots of ape diversification. o o African forms- proconsul- genus name- o § there are multiple genus’s and species. o § They are small bodied apes. Skull and teeth- consistent with modern apes in terms of molars, teeth, and skull. Have monkey like skeleton- because of small bodied nature and arm to leg length ratio. o § Also don’t have tails- make them apes. o § don't think they were great brachiators, think they were quadrapeds. o o European Forms- Dryopithecus- found throughout France, Spain, Germany. o § Unlike proconsuls, they do have the structural adaptations for brachiating. Do maintain ape like teeth. o o Asian forms o § Sivapithecus- found in south central asia, medium to large bodied. o ú Because larger bodied- probably primarily terrestrial. o ú looks a lot like a modern orangutan. Believed to be ancestors to modern orangutan. First take paleontologists compared fossils to a modern group. More fossils have been found that is more similar to modern orangutan. o § Gigantopithecus- o ú Series of giant fossils in asia, china, ú based on jaw and tooth size compared to modern primates, they believe gigantopithecus was the largest primate that ever lived. They estimate he may have been 10 ft tall and 1200 lbs. The largest primate that ever lived. Don’t know a lot about locomotion of giganto. Probably terrestrial. Will have to match geography to genus name. o · Pliocene (5-1.8 mya) o o Hominids and Hominins o § Referring to apes, hominin- fossils directly in human lineage. o · Plieistocene (1.8mya- 10kya) o o Modern humans emerge. o · Holocene (10kya-present) o Modern times- civilization and technology. · (end of geologic epics)