ANT 101 Exam 3
Supraorbital sulcus
"valley" above and behind the eye orbits
Occipital torus
(Occipital bun): sharply angled occipital bone
Age and the Ribs
- Costal cartilages attach to the ribs to the sternum - Made so when you breath it is not locked and it can expand. - Cartilage maintains attachment to ribs throughout 80+ years of life. - End of ribs collapse with age; looks like it's eroded
Upper Paleolithic
- Cultural revolution: use of stone, bone, ivory, art - Earliest rock art does not have representations of people in it - only animals - (realistic) animals tend to be painted on top of eachother - Art is not within standing reach; is very high up. Are deep in holes/caves, not anywhere that people would really see it After rock art emerges, people migrate
Lascaux Cave
- Earliest rock art does not have representations of people in it - only animals - Animals tend to be painted on top of each other - Art is not within standing reach; is very high up. - Are deep in holes/caves, not anywhere that people would really see it
Zhoukoudian, China (600 - 400 kya)
- First evidence of 'controlled' fire - Charred food remains - Burned stone tools, plants, egg shells - Used fire potentially to keep warm - Cooked food is easier to chew and releases more nutrients - Reduction in teeth size could coincide with cooking (or shortly thereafter)
Paranthropus boisei (2-1 mya)
- Found in South and East Africa - 510-530 cc - Huge posterior teeth - Robust skull: sagittal crest - Large premolars with thick enamel - Grassland
Behavior Adaptations
- Increased reliance on cognitive abilities - Increased reliance of stone tools - Increased sophistication of stone tools - Potentially shelter construction - Potentially fire use - maybe fire control - Greater social structure
Sahelanthropus tchadensis (7-6 mya)
- Sahel Desert, central Africa mixture of primitive and derived characteristics - extreme supraorbital tori -postorbital constriction - u-shaped dental arcade - 350cc - foramen magnum suggests not bipedal
Orrorin tugenensis (6.2-5.6 mya)
- Tugen Hills, Kenya - morphological evidence for bipedal and arboreal living - Obturator externus groove suggests bipedalism - phalanges curved
Sciatic notch
- Wide in females narrow in males - Pelvis is very porous and one of the first bones to decompose
Thermoregulation
- ability to dissipate heat; overheating kills your brain - Upright posture drains hot blood from brain thus cooling - Could have helped with the expansion to a large brain - Vertical posture exposes less of the body to direct sun; increased distance from ground facilitates cooling by increased exposure to breezes
Bergmann's Rule
- animal size is heat related - animal size increases in mass as you move in latitude to a colder climate - heat-adapted mammals have smaller bodies while cold adapted mammals have larger bodies
Homo
- increased brain and body size - reduction in size of teeth (specifically molars and premolars) - Obligate bipedalism - First evidence of a true forehead (development of frontal bone) - parabolic dental arcade - decreased prognathism - first projecting nose - lack sagittal crests (smoother cranial vault; globular shaped) - lack nuchal crest (smoother occipital bone)
Homo Behavior
- increased reliance on cognitive abilities and stone tools - increased sophistication of stone tools - potentially shelter construction - potentially fire use (maybe fire control) - greater social structure
Acheulean tools
- stone tools - Potential hunting in later in species - earlier species probably still scavenging. - Increase processing of food materials with tools
Pleistocene Epoch
2.6 - 11 kya
Miocene Epoch
23 - 5.3 mya
Australopithecus africanus (3.5-2 mya)
450-500 cc Life in a grassland environment
Pliocene Epoch
5.3 - 2.6 mya
Lascaux Cave
A cave discovered in 1940 and containing exceptionally fine Paleolithic wall paintings and engravings
Genetic Adaptation
Adaptation due to natural selection, changes in body size/limb proportions, skin pigmentation, sickle-cell anemia - at population level; heritable
Homeothermic
All mammals; maintain a constant body temperature despite variation in environmental temperature
Acheulian tools
Bifacial, tear-drop shaped, flaked, hand axes for chopping / scraping (butchering food).
S-shaped spine
Biped: - Cervical and lumbar vertebrae having opposing curves - Double curvature brings the center of gravity above the hips - Weight of biped is borne down the spine to the sacrum - where it passes to the hips and then legs - Vertebrae increase in size downward to absorb shock and weight of the body
Morphology for bipedalism: Pelvis
Biped: basin shaped - Supports organs - Muscle attachment areas help support and maintain center of gravity Quadruped: long and flat
U-shaped dental arcade
Chimps parallel nature of the rows of teeth along the cheeks allows them to chew up and down
Cultural/Behavioral Adaptation
Clothing, fire, shelter, marriage, kinship, division of labor, grandparent investment, etc (technological adaptation)
Great Rift Valley
Earliest hominins resided in Northern and Eastern Africa Best fossil preservation conditions for fossils
Krapina
Exhibit cannibalism or mortuary defleshing (excarnation) May be accomplished by natural means, involving leaving a body exposed for animals to scavenge (platform burials), or it may be accomplished by butchering the corpse by hand
Vasodilation
Expansion of the blood vessel diameters to move more blood (and associated heat) away from the core to the surface - Flushed red face
Morphology for bipedalism: Cranium
Foramen magnum (big hole in base of skull) is positioned centrally at the base of the cranium at the base of the cranium to allow for the skull to be in the center of gravity Quadruped: right in the back of the skull (allows them to look up when on all fours)
Prognathism
Forward placement/projection of the face (at an angle)
Piltdown Man
Found in a backyard; evidence that big cranium was first thing to evolve in humans proved to be fake in 1953
Australopithecus
Gracile: smaller lightweight skeleton Small brain but larger than previous species Small canines Precision grip All bipedal, but only one arch in foot
Parabolic dental arcade
Humans wings out the teeth towards the back of the mouth allows us to chew in a back and forth/round motion
Ape Characteristics
Larger brains relative to body size Broader, flatter faces Y5 molar pattern No tails All apes have canine premolar honing complex
Australopithecus afarensis (3.7-2.9 mya)
Lucy: 375-500 cc Parabolic shaped dental arcade Prognathic face Curved hand phalanges indicate they potentially still used wooded areas Valgus knee
Lumpers vs. Splitters
Lumpers - fewer species - anatomical variation seen as intraspecific - sees all the variation that happens in homo erectus range Splitters - More species - variation seen as interspecific -
Ardipithecus ramidus (4.4 mya)
Middle Awash region of Ethiopia - 350cc - basin shaped pelvis, double-curve spine (suggest bipedalism and living in trees) - curved phalanges, opposable toe (suggests climbing) - reduced canine size (compared to modern chimps) - prognathic maxilla
Monogenism vs. Polygenism
Monogenism- there is a common descent for all human races Blumenbach suggested differences were adaptive responses to environments. Polygenism- each human race came from a different ancestral line
Shanidar
Northern Iraq Established that teeth were used as part of their toolkit - Neandertals used incisors as tools, to hold and grasp things when they needed to use both hands Argued to be burials with elaborate flower ceremonies
Paranthropus aethiopicus (2.6-2.3 mya)
Only found in East Africa (only one skull found: black skull) - Hyper robust teeth; megadontia - Extreme sagittal crest and big posterior teeth - 410cc - Likely lived in grassland environment
Orthognathism
Opposite of prognathism; flat-face with only the nose projecting
Venus figurines
Paleolithic carvings of the female form, often with exaggerated breasts, buttocks, hips, and stomachs, which may have had religious significance
Parietal Bossing
Protrusion from the sides of the head, leading to a round skull
C-shaped Spine
Quadruped: When standing erect a c-shaped spine puts the center of gravity in front of the feet - a continuous falling forward stance Vertebrae equal in size: allows force to be evenly distributed back and forth
Cephalic index
Ratio of head length to head breadth Franz Boas proved that foreign born parents and american born children skull shaped differently - Skull shape influenced by environmental factors NOT STATIC
Fox P2 gene
Required for proper development of speech and language, found in Neandertals
Paranthropus
Robust: large, heavy boned, stout skeleton - smaller anterior teeth, larger posterior teeth, large faces (relative to gracile) - massive sagittal crest - flaring zygomatic bones - megadontia
physiological adaptation
Shivering, elevated Basal Metabolic rate, sweating, tanning, etc (acclimatization) at individual level, can be reversed A body experiences heat stress and tries to rid itself of internal and external heat Initial response: thermoregulation
post-orbital constriction
The narrowness of the skull behind the eye orbits, a characteristic of early hominins and Homo erectus.
Oldowan tools
The oldest known tools, made by chipping stones to produce a sharper edge. Made by Homo Habilis.
Benefits of obligate bipedalism
Two legs provide better balance when a biped walks, its foot falls naturally under the center of gravity for the body
Problems with habitual bipedalism
When a quadruped stands on two legs it spends a lot of energy shifting its weight back and forth between the two
Hypoxia
When body tissues do not receive adequate oxygen to function - low levels of oxygen in the blood
Pubic Arch
Wider in females and narrower in males. Helps the pelvis be wide for childbirth
Osteoarthritis
a disorder in which the cartilage between joints wears away. Visible via eburnation and osteophytes Long bone cross-sections: differential workloads produce different long bone shapes
Mousterian Technology
a stone tool technology that used the Levallois technique to produce a variety of specialized flake tools more projectile and less hefty; easier to attach to make a spear
Valgus knee
adducted femur, or a permanent knock-kneed-ness Necessary to move to the center of gravity below the hip to save energy while walking
2 foot arches
allow us to run Transverse arch runs medial to lateral Longitudinal arch runs length of food Reduce fatigue fractures in lower leg by absorbing shock and force
Wide nasal aperture
allows neandertals to warm the air they breath in because they lived next to a glacier
large infraorbital foramen
an opening in the maxillary bone of the skull located below the infraorbital margin of the orbit. It transmits the infraorbital artery and vein, and the infraorbital nerve, a branch of the maxillary nerve.
mental eminence
chin allows for muscle attachments to control breathing and speech
Vasoconstriction
constriction of blood vessels beneath the surface of skin, reduces blood flow and heat loss
Osteodontokeratic Culture
culture in which tools were made from - osteo: bone - dento: teeth - keratic: horns Established by Raymond Dart: concluded they were the result of hunters and killers whose violent tendencies had left their mark in human behavior
Megadontia
enlarged teeth diet rich in hard foods and heavy chewing
Porotic hyperostosis and Cribra Orbitalia
extreme iron deficiency Red blood cells are produced in marrow cavities Iron deficiency signals body to make more red blood cells Marrow cavities enlarged and bone becomes spongy
Cline
gradual change in some phenotypic characteristic from one population to the next
Allen's Rule
heat-adapted animals will ahve long limbs to maximize heat dissipation while cold-adapted animals will have short limbs to maximize heat conservation
Cro-Magnon
refers to the earliest found modern humans (typically European)
Enamel hypoplasia
teeth grow like rings. wearing down of a tooth's enamel
Hominoid
term for all apes that are quadrupeds, that practice habitual bipedalism
Obturator externus groove
the groove on the posterior neck of the femur for the insertion of the obturator externus muscle, a muscle that is important during bipedal locomotion.
Flaring zygomatic bones
the projection of the zygomatic bones out to the sides
Supraorbital torus
thickened ridge of bone above the eye orbits of the skull; a browridge
Harris lines (growth arrest lines)
what happens when your body stops growing because either very ill or malnourished during childhood Line in bone forms where no new bone is created.
Hypothermia
when body temp falls below the normal core temperature
Island Phenomena
when mammals get smaller when isolated on an island for a long period of time (when you put a fish in a small tank it stays small but when in a big tank it grows)
Dished face
zygomatic bones are placed forward to give the face a flat/concave appearance while viewed laterally