Term
|
Definition
-The process by which traits become more or less common in a population due to consistent effects upon the survival or reproduction of their bearers. It is a key mechanism of evolution.
-The most critical mechanism of evolutionary change -First articulated by Charles Darwin -Refers to changes in the frequencies of certain traits in populations due to differential reproductive success between individuals. |
|
|
Term
Processes of Natural Selection |
|
Definition
1. There is a struggle for existence: species can produce offspring at a faster rate than food supplies increase; more individuals are produced than can survive. 2. There is biological variation within all species. 3. This variation can be inherited. 4. Individuals that possess favorable traits or variations are more likely to survive and produce offspring. What is favorable is determined by environmental context. 5. As populations respond to pressures over time, they may become distinct species, descended from a common ancestor. |
|
|
Term
|
Definition
An allele is an alternative form of a gene (one member of a pair) that is located at a specific position on a specific chromosome.
An alternative form of a gene (one member of a pair) that is located at a specific position on a specific chromosome. These DNA codings determine distinct traits that can be passed on from parents to offspring |
|
|
Term
Mendel and Selective Breeding |
|
Definition
A practice whereby animal and plant breeders choose which animals will be allowed to mate based on traits they hope to produce in offspring.
Used it to produce "favorable characteristics" in pea plants. |
|
|
Term
|
Definition
1. During gamete production, allele pairs separate so each gamete contains one member of a pair. During fertilization, the full number of chromosomes is restored.
2. The principle of independent assortment means that the distribution of one pair of alleles into gametes does not influence the distribution of another pair |
|
|
Term
Mendelian vs. Polygenic Traits |
|
Definition
-Influenced by one gene -Expressions not usually influenced by environment -Distribution of phenotypes into just a few discrete categories
-Influenced by more than one gene -Expressions may be much influenced by environment -Distribution of phenotypes is continuous with no discrete categories |
|
|
Term
|
Definition
Molecular alteration in genetic material -Produces and redistributes variation |
|
|
Term
Factors that Produce and Redistribute Variation |
|
Definition
1) Mutation - molecular alteration in genetic material.
2) Gene Flow – the exchange of genes between populations
3) Genetic Drift and Founder Effect – the random factor in evolution, a function of population size
4) Recombination – when members of chromosome pairs exchange segments |
|
|
Term
Ecological Species Concept |
|
Definition
Focuses on natural selection and the influences of varied habitats -A species is a group of organisms exploiting a single niche, or ecological niche: the physical and biological position of the organism in the ecosystem. |
|
|
Term
Phylogenetic Species Concept |
|
Definition
When reproductive and ecological isolation can’t be defined (fossils)- splits many populations into separate species based on an identifiable parental pattern of ancestry. |
|
|
Term
|
Definition
A process that takes place when a life form rapidly takes advantage of the many newly available ecological niches.
A species, or group of species, will diverge into as many variations as two factors allow: -Its adaptive potential. -The adaptive opportunities of the available niches. |
|
|
Term
Dinosaurs and Adaptive Radiation in the Cenozoic Era |
|
Definition
After dinosaurs became extinct, mammals underwent adaptive radiation, resulting in rapid expansion and diversification. -Mammals were selected for larger brains, making them better able to process information. |
|
|
Term
Generalized vs. Specialized Characteristics |
|
Definition
-If adapted for many functions (e.g. limb with five flexible digits adapted for grasping, weight support, digging) Only a generalized ancestor can provide the flexible evolutionary basis for rapid diversification.
-If limited to a narrow set of functions (e.g. foot suited for specialized function of upright posture and walking) |
|
|
Term
|
Definition
Turns trait on or off at specific time, or not at all |
|
|
Term
|
Definition
First fish to "walk" Used large flippers to pull himself up onto land to avoid predators. |
|
|
Term
|
Definition
a group of related genes that control the body plan of the embryo |
|
|
Term
|
Definition
-flat noses with outward facing nostrils -size, diet and ecological adaptation vary -some possess prehensile tails -all diurnal (awake during the day), except owl monkey -quadrupedal, except spider monkeys are semibrachiators -most live in mixed-sex groups of all ages |
|
|
Term
|
Definition
-Cercopithecines More omnivorous with cheek pouches, arboreal, mostly found in Africa
-Colobines -Mainly eat leaves
-most are quadrupedal and primarily arboreal
-ischial callosities, hardened skin on buttocks
-sexual dimorphism- difference in size between genders |
|
|
Term
Defining Primate Social Structure |
|
Definition
Body Size Basal Metabolic Rate (BMR) Diet Distribution of Resources Predation Dispersal Life Histories Distribution and types of sleeping sites Activity patterns Human Activity |
|
|
Term
|
Definition
-Dominance Hierarchies -These impose order by establishing parameters of individual behavior.
-Higher-ranking animals have greater access to preferred food and mating partners than lower ranking individuals.
-Dominance hierarchies are sometimes called “pecking orders.” |
|
|
Term
Factors that influence Dominance |
|
Definition
Sex Age Aggression Time in the group Intelligence Motivation Mother’s social position |
|
|
Term
|
Definition
Males increase their chances of reproducing by killing infants fathered by other males. |
|
|
Term
Why are primate brains so large? |
|
Definition
Perhaps necessary for food-gathering skills -Leaf-eating primates have smaller brains -When seasonal food is available, how to extract foods from shells, hard peels, underground roots
For social living (the social brain hypothesis) -Primates must be able to negotiate a complex web of interactions
Related to meat eating -Protein and fat would help meet nutritional demands of increasing brain size |
|
|
Term
Altruism and Evolutionary Explanation |
|
Definition
-Prosocial behaviors that include assistance, sharing, care giving, and perhaps compassion.
-Altruism benefits another individual but at some potential risk or cost to oneself. -Among primates, not necessarily relatives -Evolutionary explanations: 1. Kin selection – genes still passed on 2. Reciprocal altruism – return the favor later 3. Group selection – its to the performer’s benefit that the group be maintained |
|
|
Term
|
Definition
A pattern of evolution in which the rates of evolution in one functional system vary from those in other systems. For example, in hominin evolution, the dental system, locomotor system, and neurological system (especially the brain) all evolved at markedly different rates. |
|
|
Term
Environmental Determinism |
|
Definition
links simple environmental changes directly to a major evolutionary shift in an organism. -Oversimplification: keep in mind factors like temperature, distribution of food and predators, etc. |
|
|
Term
Why Humans Became Bipedal |
|
Definition
Carrying Hunting Visual Surveillance Long Distance Walking Seed and Nut Gathering Feeding From Bushes Male Provisioning Thermoregulation |
|
|
Term
Bipedalism: Pelvis and Gluteus Maximus |
|
Definition
Pelvis: Basin-shaped pelvis supports internal organs; the ossa coxae are shorter and broader, stabilizing weight transmission.
Gluteus Maximus: Important muscles that act to extend the hip. -The attachment surface of the gluteus maximus in humans is farther in back of the hip joint than in a chimpanzee standing bipedally. |
|
|
Term
Bipedalism: Foramen Magnum and Spine |
|
Definition
The foramen magnum is repositioned farther underneath the skull, so the head is more or less balanced on the spine (and thus requires less robust neck muscles to hold the head upright).
The spine has two distinctive curves— a backward (thoracic) one and a forward (lumbar) one—that keep the trunk (and weight) centered above the pelvis. |
|
|
Term
Bipedalism: Legs and Feet |
|
Definition
The femur is angled inward, keeping the legs more directly under the body; modified knee anatomy permits full extension of this joint. Elongated lower limbs.
Enlarged big toe brought in line with the other toes; distinctive longitudinal arch helps absorb shock and adds propulsive spring. |
|
|
Term
|
Definition
-4.4 Million years old -Middle Awash in the Afar Triangle, Ethiopia -300-350 cm3 cranial capacity -4' Tall |
|
|
Term
A. Afarensis (Lucy and Salam) |
|
Definition
-around 3.3 MYA -Female -Hadar and Dikika, Ethiopia -Foot and lower limb indicate bipedal -Shoulder and curved fingers suggest climbing |
|
|
Term
|
Definition
<2 MYA Malapa Cave
-Australopith: shoulder joint, long arms with curved fingers, primitive traits in feet -Homo:Smaller teeth, narrower cheekbones, less postorbital constriction, pelvic aspects, proportionately less robust upper limbs |
|
|
Term
Narikotome Boy (AKA Turkana Boy) |
|
Definition
8 ya Cranial capacity ~900 cm3 the most complete H. erectus specimen yet found. Postcranial bones similar to modern humans |
|
|
Term
|
Definition
Dmanisi, Eurasia around 1.8 MYA These remains are the best-preserved hominins of this age found anywhere outside of Africa -They show a mixed pattern characteristics, some quite unexpected: they have small stature and cranial capacities but yet they have also found stone tools -*Broad intraspecific variation |
|
|
Term
|
Definition
-Newer technology = Acheulian tools ca. 1.4 mya -Core worked on both sides, called a biface- is flatter, more expedient -Raw materials for tools transported over longer distances -Used by |
|
|
Term
|
Definition
Earliest tools Simple, non specified Used by Early Hominins, including Dmanisi |
|
|
Term
|
Definition
850,000 - 200,000 ya -transitional species between H. erectus and later H. sapiens -likely an ancestor of both modern humans and Neandertals |
|
|
Term
|
Definition
Dali: Hard to classify - H. erectus and H. sapiens characteristics 1120 cm3 Considered to represent H. heidelbergensis
Jinniushan: 1260 cm3 Thin braincase walls Modern features unexpected for age Regional variant of H. heidelbergensis? |
|
|
Term
|
Definition
Dali: Hard to classify - H. erectus and H. sapiens characteristics 1120 cm3 Considered to represent H. heidelbergensis
Jinniushan: 1260 cm3 Thin braincase walls Modern features unexpected for age Regional variant of H. heidelbergensis? |
|
|
Term
Africa vs. Asia Heidelbergensis |
|
Definition
-Premodern human fossils from Africa and Europe resemble each other more than those from Asia -Asian fossils not as clear: they seem more modern than contemporary African fossils. Early H. sapiens? -African H.h = modern humans; Asian premodern populations = ? |
|
|
Term
Middle Pleistocene Culture Toolkit |
|
Definition
Acheulean tool tradition replaced near the end with Levallois tool tradition in Africa and Europe (slightly more sophisticated)
(Use of large chip as spearhead)s |
|
|
Term
Middle Pleistocene Culture Shelter |
|
Definition
Lived in both cave and open-air sites Probable use of fire Temporary shelters (bones, stones, artifacts) |
|
|
Term
Middle Pleistocene Culture Hunting and tools |
|
Definition
-Exploited wide variety of food sources (fruits, veggies, seeds, nuts, birds eggs) -Exploited marine life (NEW) -Little evidence for hunting except wood spears from Germany |
|
|
Term
Classic Neandertals, western Europe |
|
Definition
-1520 cm3 cranial capacity (perhaps related to metabolic efficiency of larger brain in a colder climate) -large, low, long, and bulging cranium -bun-shaped occipital bone -vertical forehead -arching brow ridges |
|
|
Term
|
Definition
-Northern Spain -49,000ya -12 individuals found together, bones smashed, butchered and likely cannibalized -Likely belonged to same social group -Males closely related, but not females. Evidence of patrilocal mating? -Possibly bones brought to cave postmortem? |
|
|
Term
|
Definition
-South Western France -35,000 ya -Possibly coexisting with modern H. sapiens -May have borrowed methods, interbreeding with modern H. Sapiens |
|
|
Term
Chatelperronian tool industry |
|
Definition
-Included discarded chipped blades and hand axes, Upper Paleolithic tools -May have borrowed methods, modifying their own into this -Used by some of "Last Neandertals" |
|
|
Term
|
Definition
-male, appx. 30-45 years old -5 feet, 7 inches tall -1600 cm3 cranial capacity -Extremely injured/damaged before death, and lived with injuries for some time. -Would have had to have been cared for |
|
|
Term
|
Definition
-associated with not just Neandertals (found in context with modern humans). - Improved on Levallois technique -Varied tools, but none for long distance throwing |
|
|
Term
Neandertal Subsistence Strategies |
|
Definition
Included hunting large mammals, although less efficiently than modern humans. -No long distance weapons meant more prone to serous injury -Injuries similar to rodeo performers, suggesting close encounters! -Exploited marine resources, gathering shellfish and hunting seals and dolphins |
|
|
Term
|
Definition
-deliberately buried dead as early as 90,000 years ago at Tabun -Disposal of dead evidenced at Simia de los Huesos, Spain, 400,000 ya. -Bodies modified and placed in flexed position at 16 of the 20 best documented burials. -Grave goods placed in burials, e.g. stone tools, animal bones, stone slabs, flowers: questionable -Possibly shows concept of spirituality |
|
|
Term
Regional continuity model |
|
Definition
-Multiregional evolution -Local populations in Europe, Asia, and Africa continued indigenous evolutionary development to anatomically modern humans -the earliest modern human populations did not originate exclusively in Africa -Significant levels of gene flow between geographically dispersed populations occurred throughout the Pleistocene |
|
|
Term
Complete Replacement Model |
|
Definition
-Modern populations arose in Africa <200,000 ya, migrated, replacing populations in Europe and Asia |
|
|
Term
Partial Replacement Model |
|
Definition
-Postulates that human-Neandertal intemixing occurred 80-50,000 years ago, possibly in the Middle East. -Patterns of dispersal will become more clear with increased genomic data |
|
|
Term
|
Definition
More interbreeding took place in some regions |
|
|
Term
Modern humans in Near East |
|
Definition
-Skhūl Cave, Mt. Carmel, 130,000 – 100,000 ya -Qafseh Cave, Mt Carmel, 120,000 – 92,000 ya -Tabun Cave, Mt. Carmel, 120,000 ya
possible human-Neandertal interbreeding sites. |
|
|
Term
Abrigo do Lagar Velho, Portugal |
|
Definition
-24,500 ya -4 year-old child -buried with red ocher and pierced shell -teeth, lower jaw, and pelvis represented modern human anatomy -lack of chin, limb proportions, and muscle insertions were similar to Neandertal suggests interbreeding -Neandertal/Human Hybrid? |
|
|
Term
|
Definition
-Small body, 3 feet tall -Small brain, 417 cm3 -Hand and foot anatomy resembling H. erectus from Dmanisi -Stone tools dating 1 mya -May derive from early migration of early Homo to SE Asia -Represent isolated island population showing considerable dwarfing |
|
|
Term
Upper Paleolithic culture |
|
Definition
-Subsistence from tundra and steppe vegetation, with flowering plants and vegetation in short summers with abundance of herbivorous animals, fish and fowl -Caves and open-air camps, built large shelters -Elaborate burials |
|
|
Term
|
Definition
-Apollo 11, 28,000 – 26,000 ya -Blombos Cave, 73,000 ya -Pinnacle Point, 165,000 ya -Katanda, 80,000 ya |
|
|
Term
|
Definition
Cultural and biological variations are inherited (e.g. intelligence, morals, values are inherited like biological traits). |
|
|
Term
|
Definition
"race improvement“ through forced sterilization and encouraged reproduction. |
|
|
Term
processes biological anthropologists study with regard to differences in physical traits among human groups |
|
Definition
-population adaptation -genetic drift -mutation -gene flow |
|
|
Term
Race in regards to Intelligence |
|
Definition
-Genetic and environmental factors contribute to intelligence. -Many psychologists say IQ scores measure life experience. -Innate differences in abilities reflect variation within populations, not differences between groups. -There is no convincing evidence that populations vary in regard to intelligence. |
|
|
Term
Race vs. "Typical" Characteristics |
|
Definition
Racial categories are based on stereotypic or ideal traits
They are typological in nature (based on “typical”) -In any racial group, there will be individuals who fall into the normal range of variation for another group for one or several characteristics. -Two people with different ancestry with different skin color could share other traits, such as height, shape of head, hair or eye color, and ABO blood type. |
|
|
Term
|
Definition
traits (or DNA sequences that code for them) that differ in expression between populations and individuals
used to understand evolutionary processes in modern populations |
|
|
Term
|
Definition
focuses on variable DNA polymorphisms |
|
|
Term
|
Definition
-reported ca. 15 million SNPs -determined molecular basis for 95% of fairly common patterns of variation -identified 50-100 gene variants associated with disease
*Genetically, humans differ individually within populations far more than large geographical groups differ from one another. |
|
|
Term
Factors that cause allele frequency changes in modern human populations |
|
Definition
-Production of new variation (mutation) -Redistribution of variation through gene flow or genetic drift -Selection of “advantageous” allele combinations, promoting reproductive success (natural selection) -Nonrandom mating |
|
|
Term
Assortative Mating vs. Inbreeding |
|
Definition
when individuals of either similar of dissimilar phenotypes mate more often than would be expected
– relatives mate more often than expected, reducing genetic variability, potentially reducing reproductive success |
|
|
Term
|
Definition
Evolutionary processes are understandable only within a cultural context -Slash-and-burn agriculture related to spread of sickle-cell allele in West Africa |
|
|
Term
|
Definition
-To survive, all organisms need to maintain normal functions of internal organs, tissues and cells. -Temperature, wind, solar radiation, humidity -Physical activity also places stress on physiological mechanisms -The body must accommodate all these changes by compensating in some way to maintain internal constancy |
|
|
Term
Long term evolutionary response |
|
Definition
1. responses to heat (sweating) 2. excessive UV light (dark skin near the equator)
characterize all individuals within a population or species. |
|
|
Term
|
Definition
Short-term, long-term, or permanent physiological responses to environmental stressors. These can be influenced by genetic factors as well as: -duration and severity of exposure -technological buffers (shelter or clothing) -individual behavior -weight and overall body size -*Rapid, e.g. tanning or increase in hemoglobin production when traveling to higher elevations (temporary) -*Developmental, exposure to environmental challenges during development, e.g. physiological responses in lifelong residents of high altitude (permanent) |
|
|
Term
|
Definition
Hemoglobin Carotene Melanin |
|
|
Term
UV radiation as a selective agent in human evolution |
|
Definition
-Early hominids lived in the tropics, where solar radiation is intense, and spent their days outdoors. -didn’t wear clothing that would have protected them from the sun. *UV radiation was powerful agent selecting for maximum levels of melanin production as protection. |
|
|
Term
Folate B and skin evolution |
|
Definition
-More UV radiation = less folate -Insufficient levels in pregnant women associated with numerous fetal developmental disorders |
|
|
Term
Vitamin D and Skin evolution |
|
Definition
-The need for a UV filter was outweighed by the need for vitamin D -Needed to absorb calcium (bone growth) -May provide protection against prostate and colon cancer -Reduces inflammation and eventually may be used to treat diseases, including multiple sclerosis |
|
|
Term
Vasilodation vs. Evaporative Cooling |
|
Definition
or flushing, which is when capillaries near the skin’s surface widen to increase blood flow to the skin
Way in which sweat glands making it possible to lose heat |
|
|
Term
|
Definition
In mammalian species, body size tends to be greater in populations that live in colder climates. As mass increases, the relative amount of surface area decreases proportionately.
Because heat is lost at the surface, it follows that increased mass allows for greater heat retention and reduced heat loss. |
|
|
Term
|
Definition
In colder climates, shorter appendages, with increased mass-to-surface ratios, are adaptive because they are more effective at preventing heat loss. Conversely, longer appendages, with increased surface area relative to mass, are more adaptive in warmer climates because they promote heat loss. |
|
|
Term
Short-term responses to cold |
|
Definition
-Shivering -Increases in metabolic rate to release energy in the form of heat -Narrowing of blood vessels to reduce blood flow from the skin, vasoconstriction |
|
|
Term
Tibetans and High Altitude Evolution |
|
Definition
-Been living higher than 12,000 feet for 7-25,000 years -You don’t see the negative effects on reproduction (high infant mortality, low birth weight, preeclampsia in mothers) Glucose is burned in a way that permits more effective oxygen use -90% of Tibetan highlanders have a mutation in a gene EPAS1, which inhibits increased red blood cell production normally present at high altitudes (very high levels cause stroke, etc.) |
|
|
Term
|
Definition
-All humans lived in small nomadic hunting and gathering groups with little contact with vectors, or carriers of disease; -Diseases were not endemic, or continuously present, because humans lived in small bands. -exposure to domestic animals provided environment for spread of zoonotic diseases, e.g. tuberculosis |
|
|
Term
Hypothesized origin of HIV/AIDS |
|
Definition
The original selective agent was NOT HIV *Smallpox? |
|
|
Term
|
Definition
refers to the increase in mass or number of cells
refers to the differentiation of cells into different types of tissue and their maturation |
|
|
Term
|
Definition
The skeleton begins as cartilage, gradually broken down and replaced by bone cells |
|
|
Term
How do anthropologists estimate age at death with skeletons? |
|
Definition
Epiphyses (ends of bones) unite with shafts (middle section of bones) in predictable patterns |
|
|
Term
|
Definition
At birth, the brain is ca. 25% of its adult size Doubles by 6 mo. Near adult size by 10 year |
|
|
Term
Nutrition and development
Thrifty Gene Hypothesis |
|
Definition
-Prenatal nutrition affects development of fetus
we are predisposed to favor foods high in fat because of our previous “feast or famine” conditions |
|
|
Term
Epigenetics and "Nature vs. Nurture" |
|
Definition
studies “nature vs nurture” determinants and calls into question genetic determinism for many traits. -the way in which gene expression unfolds in a growing individual is influenced by environmental factors (turning on and off some genes) |
|
|
Term
4 primate life stages
and 5th human |
|
Definition
Gestation – conception to birth Infancy – nursing period Juvenile – weaning to sexual maturity Adult – completion of growth
5th in humans – post reproductive years |
|
|
Term
Pregnancy, Birth, and Infancy |
|
Definition
Birth takes place in the context of culture, a social event unlike that for most other mammals. 3 year period of breast-feeding for most humans in evolutionary past, serving as a natural birth control. Human milk is low in fat and protein, suggesting mothers are seldom or never separated from infants nursing in short, frequent occasions. Human milk provides important antibodies. |
|
|
Term
|
Definition
-Growth in stature -Brain growth -Acquisition of technical and social skills |
|
|
Term
|
Definition
Rapid growth and increase in body size Change in body shape Development of testes, penes and breasts Hormonal changes are the driving force behind these alterations Reproductive functioning begins |
|
|
Term
Menarche age changes in Western society |
|
Definition
going down: in history, once you accumulated enough body fat you could reproduce – we are now obtaining that sooner as we are more well nourished |
|
|
Term
Long life after reproductive age theories |
|
Definition
-life expectancy has increased due to advances in standard of living, hygiene, medical care
-Age is a gradual decline in: cells’ ability to synthesize proteins, immune system function, muscle mass and strength and bone mineral density
-Genes that enhance reproductive success may have detrimental effects in later years |
|
|