Notes for ANTHP 105 PDF

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3/9 1. Human origins & world wide expansion Because we are all mostly genetically similar, the differences in population are mainly due to genetic drift and mutations. (replacement model is the correct model) - Interbreeding and gene flow are powerful forces in the human species. Occur all over the world. - There are no pure populations. We’re all from one big mixed gene pool. 2. Serial founder effect: - The more distance away from africa= more genetic difference. BUT. the differences in genes are very small. This is not a huge difference in genes through all populations. These changes that occur as populations move farther away from africa are due to the effects of drift and mutation. 3. Local adaptations: these changes to human populations are shaped by Natural Selection: these are local changes, based on that local environment. The environment affects selection. a. Skin color: Relates to sunlight/Ultraviolet Radiation (UVR). More sunlight (ex in africa)= darker skin. Less sunlight ( europe)= lighter skin. IN MOST SITUATIONS, this is not always the case. - UVA: Penetrates deeper into skin (destroys folate) - UVB: Penetrates superficial layer of skin. (stimulates production of vitamin D) - Bad effects: Too much UV rays can damage folate: disrupts DNA synthesis. Causes anemia, cancer, sunburn. Etc - Good effects: you need a certain amount of UV rays, or sunlight, to produce vitamin D. - People living in areas of High altitude, have less UV rays ( meaning less sunlight). This means they have less melanin and their skin color is lighter. High altitude= less melanin=light skin color. In most cases. - BUTTTT: since they do not have as much UV rays for the production of Vitamin D, they maintain or increase vitamin D levels by eating aquatic animals ( high in vitamin D). - People in alaska have higher levels of melanin: darker skin: because of the increased ingestion and digestion of aquatic foods. - Low altitude= MORE UV RAYS , more melanin= darker skin; melanin protects folate from being destroyed. THis is why darker skin people don’t age as quick, sunburn as easy, or get as high amounts of skin cancer than lighter skin people do. b. Body proportions: Adaptations in Body shape and size due to climate. i. Allen’s Rule: pertains to limb size and climate: 1. Warmer climate= Longer limbs. Increase surface area to release

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heat. 2. Colder Climate= Shorter Limbs. Decrease surface area to retain heat. Bergmann's Rule: Pertains to Body size and climate, (weight/fatness): 1. Warmer climate: smaller body size, lighter, not as fat. 2. Colder climate: Heavier, bigger body size; fatter. Body mass or weight is greater in colder temps.

c. Altitude: Independently evolved adaptations to thin air. i. TIbet: place of high altitude.This is a place of thin air, with less oxygen and less air-pressure 1. It is possible that you produce higher levels of RBCs: SO that more hemoglobin can compensate for the low levels of available oxygen. ii. Andean: closer to the equator. Low altitude: more O2 and higher air pressure. d. Malaria (parasite by mosquitos) resistance: i. Culture effects biology: Farming increases numbers of mosquito habitats. ii. There are Many independently evolved adaptations for malaria resistance world wide: there are different ways that are not related to each other that come about to resist malaria. iii. Sickle Cell Anemia: this is the most common adaptation to combat/ resist malaria. 1. It is caused by sickle cell alleles, changing the shape of the RBC so that it cannot do its job properly,. 2. Sickle cell trait has to be heterozygous to both protect against malaria and not have sickle cell anemia. 3. AA- have resistance but have sickle cell- low fitness 4. SS- NO sickle cell but no resistance- low fitness 5. AS- highest fitness, no sickle cell and some resistance iv. Malaria is in areas that are in rainforests, wet, area = a lot of mosquitos v. We have populations that are resistant to certain insecticides such as BBCs, chlorocholine (anti-parasitic) e. Lactase (enzyme that breaks down lactose--sugar bound in mother’s milk) persistence: i. Majority of mammals are lactase- non persistent ii. lactase= enzyme . Supposed to end at weaning iii. We continue to break down lactase in some populations: occurs independently 1. Happened in europe: highest persistence in areas using cattle and milk. Not all people lactose non-persistence are lactose intolerant and vice iv.

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versa. Pastoralism: herding and breeding cattle Allele to digest milk as an adult evolved independently in europe and a Independently evolved, bc independently herding cows.

3/13/18 1. Hunter-gatherer societies as in human evolution and health a. Heart disease, diabetes and obesity have reached epidemic levels in the developed world because of modern way of life is radically different from the hunter gatherer environments in which our bodies evolved. b. There is no energy difference in what we do and what the hadza do: it looks like they do more work but, we spend the same amount of energy as the hunter gatherers do. c. The obesity problem is that we eat too much and consume too many calories. Not bc of a lack of exercise d. Hadaza do not get heart disease or diabetes like westerns do because we eat way more than they do. e. We sleep the same about as hunter gatherers: regardless of electricity access. ~7.5 hrs. f. Hunter gatherers do not burn more calories than we do, they are not more physically active, obesity is due to EATING TOO MUCH. 2. The hadza : a case study of hunter-gatherers in Tanzania, Africa a. Their environment : i. The African Savannah ii. Simple grass huts, with no guns, vehicles, crops, or livestock. b. Social organization: Egalitarian social structure- no sole leader/chief, no government or hierarchy/classes. Everyone is equal. - Live in families → extended family→ groups of extended families make up the camps→ the entire tribe is the language group. - 1,000 people identify as hadsa, 300 are nomadic and collect food: true hunter gatherers. - Other 700- mixed subsistence. Used supplement and store bought food as well as some substancience farming - Swahili is the language i. Sengali Camp & Setako Camp c. Foraging ( getting food) strategies i. Women: leave camp together to collect plant foods. They do the foraging and gathering- using the digging stick to search for food, 1. Women contribute half of the food eaten by a camp 2. Gathering berries, baobab fruit: tree, tubers: yams to roast- very fibrous ii. Men: they leave camp alone to hunt - Use bow and arrows, - Hunt for for antelope (meat), to collect honey they share everything: important for this group

- Use bows and poison tip arrows - Doing many miles to hunt 15-20 miles iii. Kids and elderly stay near camp: help in any ways possible, getting water, sorting fruits and seeds, etc. - Water can also be collected from baobab trees, d. Diet: hunting and gathering: Their diet is high in protein, not much fat or sugar. i. Setako Camp: They get most of their caloric intake from berries. 1. Berry, meat, tuber, honey ii. Sengali camp: most calories from baobab fruit, 1. Baobab, meat, honey, tuber. iii. Meat is not the most important part of diet, bc hunting is hard and dangerous.

3/16/18 Importance of diet in Biology & evolution Origins of primates: 2 hypotheses. 1. Angiosperm Coevolution: primates evolved to eat fruit and terminal branches of trees a. Fruiting plants and primates coevolve: Plants provide a fruit/Food source and primates help disperse their seeds. 2. Nocturnal Visual Predation: Binocular vision and rasping hands evolved to hunt insects at night : this is common in small bodied primates. 1. Human diets vs other apes a. Human diets: (human gatherers) are very different from those of other apes. Humans: eat meat,fruit, and roots. - Cooking and sharing are behaviors: diets affects behavior of how to prepare and give away food. B. Ape diet: - chimps: mostly fruit, some leaves. Little meat/ bugs/ animals. - Gorillas: mostly leaves, some fruit, little meat. 2. Trophic pyramid: All energy comes from the sun, and supplies each a. Sun → plants (producers) → Herbivores ( Primary consumers) → Carnivores (secondary and tertiary consumers). 3. Basic food properties: energy vs. abdunance - Primates ( including humans) eat a variety of foods: these foods have different properties a. Leaves and structural parts of plants: low in energy, but very abundant in nature b. Seeds: important in human diet - Often hard to digest; protected by chemicals and shells - Ex sunflower seeds, nuts C. Fruit: high in energy, easy to digest, less abundant than leaves - Ex: apples, figs, grapes,

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In normal nature, very hard to grow and find ( not easy like how humans have farms D. Root vegetables (USO’s Tubers): foods found under the landscape, under the dirt - High in energy, but difficult to find and harvest ex: potatoes , yams, onions, carrots humans and baboons eat these the most E. Meats ( including insects ) : Highest in energy and protein, but difficult to get. Primates ( including humans) eat a variety of foods: these foods have different properties - High quality food ( high in energy) are less abundant - Low quality foods are more abundant **quality is measured in terms of energy) ** see picture 4. Kleiber’s law and Food quality VS body size a. Larger animals burn more energy per day but pound for pound small animals burn energy must faster. b. Smaller animals have higher quality diets, they need higher energy foods. c. Larger animals can survive on lower energy diets, d. K’s law= calories/day= k Body mass ^ 0.75. Body mass and energy expenditure are not directly proportional ( 1-1). e. Humans are an exception to this rule: we eat higher quality diets for our body size. 5. Adaptations to different diets: there are physical and behavioral changes that happen because of the different diets eaten. a. Frugivores: mostly eats fruit - They have big incisors - Low rounded molars b. Folivores: Mostly eat leaves. - Small incisors - Molars with shearing crests. C. Colobine monkeys: have sacculated stomachs , which is an adaptation for digesting seeds and leaves. These Folivores have to have the extra adaptation of sacculated stomachs in their digestive system to be able to process the leaves and shit. Adaptations in Brains and Behavior: D. Primates: because high quality foods are hard to find, their intelligence had to adapt to find food. Need to be smarter to find it. - Color vision, emphasis on visual and tactile cues for fruit ripeness. - Tools and bring smart brains adapt: being smarter allows access to more foods. - Diet and brains : high quality foods are hard to aquire- creates selection for intelligence to find food - Spider monkey: frugivore: smalle digestive tracts - Howler monkey: folivore: large digestive tracts: leaves are harder to process. (sacculated stomachs) Diet and brain size:

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Homo habilis- oldowan tools ( smallest brain simples tools) Homo erectus: acheulean tools Homo heidelbergensis: levallois tools Least complex tools→ most complex toolskk Smallest brain→ bigger brain

6. Food quality vs territoriality: Less quality food= less territorial, Higher quality foods= more territorial. a. In the rainforest, fruit trees are rare and patchy. Even though fruit trees give more energy, they're not found in abundance. b. Leaves are abundant and common c. Because leaves are more abundant, Folivores are LESS TERRITORIAL: they can afford to share and do not have to claim certain areas of food for themselves because food is all around them. EXAMPLE: howlers and colobus. d. Frugivores are more territorial. EX: Chimps and gibbons. Fruit trees are rare so whoever finds it first is going to claim it as their territory. 7. Optimal foraging theory: organisms try to maximize energy gain, but minimize effort. i. Primates will not do what is not necessary to gain energy. - Folivores cannot possibly own all areas of leaves, - Frugavore will be more territorial because it's necessary for their max energy gain. - This works for primates, but not for humans. 3/20/18 Importance of Diet in Biology and Evolution. There is no single traditional diet, tradition populations focus their diet around the local landscape. - Warm climates= more plants - Cold climates= more meat. 1. Local adaptations to diet: a. Lactase: cultures that depend on milk for food (dairy farming) Have evolved the ability to digest milk as adults. i. This is independently evolved in europe and africa because or independant pastoralism= independently herding cows. b. Salivary Amylase: Digests starches. i. Populations with high starch diets ( tubers,rice, etc). Have more copies of salivary amylase gene, . 1. they produce more amylase to digest starch - positive directional selection: more copies. c. Arsenic detoxification: - water in the atacama desert in chile naturally has high levels of arsenic - The Population of people that live there has high frequency of an allele that clear arsenic from the body.

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70% of the atacama population has an allele for AS3MT gene that speeds arsenic clearance, Spefically an allele that speeds the arsenic clearance.

2. How bodies use: a. Carbs: Bodies 1st source of energy. - Bread, sauce, sugars: enters blood stream and breaks down to give the body energy b. Fats: The second source of energy - Meat and cheese add to the fat in the body. - When there are low amounts of carbs and sugar, the body breaks down fats to get energy - This works for weight loss, and is why people go on low carb/ low sugar diets, so that you can break fat down and lose weight. But if you don't keep up the diet you will gain the weight again. - Low carb or low sugar diets make your body use fat for energy. Help prevent build up of fat from sugar. c. Proteins: This is the last and dangerous type of energy source - The body breaks down muscle/tissue/protein to get energy. This happens during starvation - Glycogen= carbohydrate reserves that are stored as fat. - Humans feel full and stop eating when we get enough protein More carb and fats eaten then protein= gaining more weight 3. Microbiome: each person has one hundred trillion bacteria , viruses, and fungi living and on our bodies . thousands of different species. a. 10 bacteria for every 1 human cell. 1-3% of your weight is bacteria ! - Gut microbiome diversity: USA has less bacterial/microbiome diversity then traditional populations in venezuela and malawi. - Your gut ecology develops with age . Both genetics & environment affect it. - People are born without gut bacteria, it is introduced to you. Gut microbiome may affect health - Tests in mice show relationship between gut microbiome and obesity. - Relationship between microbiome and physiology - Mix of gut microbiome may play a role in crohn's disease. 4. Hygiene Hypothesis:Low rates of infection leads to more autoimmune disorders (allergies, asthma, autoimmune disorders) in developed countries- This means: When you are not exposed to these specific bacteria you develop autoimmune disorders - USA and europe= low rates of infections, higher levels of auto-immune disease. - Africa: high rates of infection, But low amounts of autoimmune diseases. THIS IS WHY VACCINES work: they do not cause autism. 3/23/18

Diet and behavior: social organization in Apes & humans male vs. female strategies 1. Social organization in apes and humans male vs female strategies. 2. Polygamy: having multiple mates 3. Polygyny: this is the social structure.1 male having multiple female mates. 4. Polyandry: 1 females mating with multiple males 5. Polyandrogyny: both sides having multiple mates Social strategies: the difference in how an individual lives within their species, differneces between species - Social behavior/ strategy evolved themselves, they don't just choose to act this way. Should primates live in Groups, or Alone ( solitary)? - Living in groups: elephants, wildebeests, gellota monkeys, - Solitary: polar bear, leopard, lorus. How does diet affect social strategies and the evolution of them. How is diet one outside force that drives the way that animals live? - Benefits of living in a group: 1. Predator awareness and defense. - EX: vervet monkey alarm cells: they have a special call sound they make for each threat ( bird, leopard, snake) that come around. - It alarms others in the same species so that they get to protection. - You have a group of people to help you defend against predators. - Callback vocalization: record verbate monkey, play it back to them when there is no predator. Observe reaction - Calls are contested: hear different types of calls

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2. Resource defense: territory defense in Chimpanzees Defend your territory beyonds with force or threat of force. Different diets lead to different territoriality Not all primates are territorial. Chimps are territorial: because they are frugivores, more territorial because there is less fruit available. 3. Cooperative foraging: - Ex: cooperating hunting: in cape hunting dogs & some human groups. - Cooperative Hunting and finding food to share together. - Humans are the only primates that routinely forage together. 4. Care of infants and juveniles. - EX: cooperative child care in marmosets and humans. - Kids Are a burden on females - Marmosets: monogamy and polygamy. They have twins most of the time: energy burden on mom, need to produce milk/ energy for 2 offspring now. - Females, even tho small give birth to 2 offspring 20-27% of their body weight. - Bc of the huge energetic burden, there is more cooperation between male and

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female marmosets. More energy spend by males, neighbors, and siblings on offspring. Humans: grandparent hypothesis, sibling: help take care of offspring. Monogamous relationship= usually the male in investing more energy vs if it was a non-monogamous relationship.

COSTS TO GROUPS: 1. Competition for food and mates - Scramble competition: not actual physical contest, but more of a competition for space and resources that are finite (there is a limit to how much of it is available).the more people, the less space/less resources there is for everyone else. More people= more competition = less resource -

Contest competition: verbally, and physically fighting for resources.

2. Risk of disease and parasites: - if a virus was to spread in a city, vs a rural area: it would spread more quickly in a city because there is more contact with people - The bigger the group, the higher the chance for diseases to spread. 3. Interference with reproduction: - Ex: infanticide: killing infants . rare but primates do it. - Particularly common in 1 male, multiple female groups/ social structure - Males selectively kill infants of females in a group of which they’ve just taken over. - Male takes over another group, defeats the men and takes over the women, may kill their children - Since those infants are not their biological offspring, the male kill the infants of those women - Lions also do this as well: 1 male, multi female group. - This happens because, this behavior evolved because: - Not your offspring not gonna spend resources on it - Females that have to take care of babies reduces chances of her reproducing, so they kill the infant = more mating success. - Psychological perspective: jealousy, dominance, we have no idea really. nothing to do with monkeys brain. Not really known - This behavior is evolved, not in their heads, not motivated emotionally - This behavior is biology: they don’t think in the senses that we do.they don’t determine what’s good and bad Standard social-ecological model: -- what factors limits reproductive fitness: different factors for females and males A. Females: food, resources, risk of predation: These factors can stop them from reproducing. - Female group size must correlate to maximize the access to food and

protection from predators in order to have a high reproducing rate. B. Males: mating opportunities, access to females: if a male cannot find a female to reproduce with, they can’t reproduce. - Males will try to maximize their access to females. Common social organization in monkeys: Main group: few male...