ANTH Mid 2
Lunate Sulcus
Def: : It divides the parietal and occipital regions of the brain, and located along visual cortex of Apes and Humans Sig: Based on the relative position of the lunate sulcus, researches argue for/against the potential language capabilities in australophithecines
Herbivory
Def: A diet of vegetation Sig: Can trace heterodont dentition in primates by looking at their "thoothcombs"
Dietary plasticity
Def: A diet's ability to adapt to the environment and change. Very important to surviving long term. Sig: We've retained our primitive dental characteristics (molars, pre-molars, incisors, canines) to
Knucle-walking
Def: A form of movement characterized by all four limbs touching the ground, with the weight of the arms resting on the knuckles of the hands
Taung child
Def: A fossil from T'aung South Africa (aprox 3.3-2.4 mya), discovered by Raymond Dart in 1925, and named Australopithecus africanus Sig: Contradicted the Piltdown fossils, and offered first authentic hominin ancestor
Primate
Def: A group of mammals in the order Primates that have complex social behavior, varied forms of locomotion, and a unique suite of traits, including large brains, forward-facing eyes, fingernails, and reduced snouts Sig: Primates are very adaptable- variable diets, can live anywhere, although adapted to life in trees (arboreal hypothesis), have a lot of parental investment. By understanding the adaptations that all primates share, we can understand what has evolved into the human lineage.
Australopithecus garhi
Def: A homini, found in Ethopia, about 2.5 mya, that had a homo-like ratio of upper arm-length to upper-leg length Signifcance: This humanlike ratio, combined with cranial, dental, and postcranial features, leads some to suggest that this is ancestral to homo.
Paranthropus boisei
Def: A homini, from East Africa, around 2.5-1.5 mya, with robust cranial traits of large teeth, face, and muscle attachments. Sig: The 'robust' lineage diverges away from modern humans (gracile line), probably because they went extinct because of their vigorous dietary specialization/adaption to foods that require heavy chewing.
Paranthropus (Australopithecus) robustus
Def: A homini, from South Africa, around 2 mya, with robust cranial traits of large teeth, face, and muscle attachments. Sig: The 'robus' lineage diverges away from modern humans (gracile line), probably because they went extinct because of their vigorous dietary specialization.
Brachiation
Def: A method of movement that uses the arms to swing from branch to branch; Adaptations in the hands and forearms allow for this motion. Sig: Human evolution progressed to a more equal ratio of arm-leg length, allowing for bipedal locomotion.
Bonobos
Def: A primate, considered an African grate ape from south of Congo river with social groups Sig: One of the closest extant living relatives to homo sapiens, alongside chimps
Bowl-shaped pelvis
Def: A type of pelvis variation that helps improve balance with regard to body weight and muscles. Sig: In the absence of a bowl-shaped pelvis, torque produced by body weight would compel body in one direction (chimps swaying). With the bowl-shaped pelvis, balanced bipedalism becomes possible. Important development in hominin movement towards bipedalism.
S-shaped spinal column
Def: An S-shaped spinal column, as in homo sapiens, brings body weight over feet, and allows range of movement; bending, stretching, and twisting. It is a consequence of evolutionary balancing in bipedalism. Sig: This is one of the ways bipedalism has shaped the skeleton in humans -- back pain is one of the most common issues in humans due to so much pressure being placed on the spine, shows how not all evolutionary adaptations are 100% positive.
Australopithecus anamensis
Def: An early hominini, primarily from Kenya, around 4 mya, possessing ape-like attributes (U-shaped dental arcade) and homo-like attributes (tibia.) Sig: First definite bipedal (not necessarily obligate though, could have been facultative) because tibia and ankle-bone indicates regular bipedal walking (support of body weight on one leg at the time). [OR, The still U-Shaped jaw, resembling the Apes mandible, indicates to researches that this was the earliest australopithecus as later hominins boasted the C-shape mandible.]
Homo erectus
Def: An early homo species, dated in (Kenya), aprox (1.8 mya-0.3 mya) with substantially large brains, but also reduced in size back chewing teeth. Sig: These featues suggest that H. erectus is the most reasonable of the early Homo species to be considered ancestor to later in time hominids like homo sapiens
Homo habilis
Def: An early homo species, known from sites in Tanzania and Kenya, living aprox (1.7-1.8 mya), slightly increased cranial capacity, smaller dentition with C-shape than the australopithecines. Sig: Important because of increased brain size and associated with stone tools, increased sophistication and movement away from australopithecines; evidence suggests possible ancestor to homo erectus.
Pleistocene
Def: An epoch from 2.6 mya- 0.12 mya, coincides with Paleolithic period. Sig: Characterized by the creation and use of rudimentary chipped stone tools by hominins.
Raymon Dart
Def: Australian anatomist and paleoanthropologist who discovered the T'aung fossils. Significance: In 1924, discovered the first Australopithecus africanus fossil at the Taung site in South Africa; contradicted the Piltdown "Man" hoax
Paleolithic
Def: Coincides almost exactly with the Pleistocene epoch, Lasted from 2.6 mya to 12,000 years ago. Characterized by the creation and use of rudimentary chipped stone tools. Sometimes called the Old Stone Age. Ended with the Neolithic Period, occurred about 10,000 years ago Significance: tools in the Paleolithic were related to fire, shelter, art, and burials. First artistic behavior was seen in the Upper Paleolithic.
Australopithecus afarensis
Def: Early hominini, found in Ethopia, around 3.5 mya with very similar skeletal structure as humans (like iliac bone). Sig: Lucy, one of the most complete fossils, was a afarensis, and because her bones, like her iliac bone and bowl-pelvis resembles homo sapiens' bipedal features, made clear this possible ancestor was a habitual biped. (Also no-divergent big-toe footprints)
Ardipithecus ramidus
Def: Early hominini, found in Ethopia, around 4.4 mya. Possessed anatomical ape-like qualities (small brain) and hominin-like qualities (little sexual dimorphism, toes, short illiac blade) Sig: The short illiac blade and toes resemble later hominins, indicating that these were bipedal, and possibly placing them in our direct lineage. [For possible essay, they had intermediate form of bipedalism, not evolving from tree-branch swinging; moved on its palms and feet along branches and walked upright on ground; not a knuckle-walker, because of non-opposable big-toe]
Australopithecus africanus
Def: Early hominini, found in South Africa, around 3-2 mya, and gracile australopithecine; ape-like leg-to-arm ratio Sig: T'aung, discovered by Raymond Dart in 1925, contradicted the Piltdown fossils, and offered first authentic hominin.
Australopiths
Def: Early hominins characterized by combination of ape-like and human traits like some bipedalism but ape-sized brains (about 3 mya). Sig: Possible that one of these species, like garhi, who share homo traits (ratio of humerus to femur length) were ancestors.
Piltdown "Man"
Def: Fossils "found" in England by Charles Dawson, possessing ape-like teeth and human braincase; later discovered to be fraud. Sig: The existence of this hoax contributed to criticism against T'aung, an authentic fossil, and delayed acceptance of the early hominin Australopithecus.
Pongo
Def: Genus referring to the orangutan Sig: of the family Hominidae, a great ape, one of our closest relatives- by studying their behaviors and anatomy, we gain insight to how our ancestors behaved. Also sheds light on ancestral vs. derived traits in humans.
heterdont dentition
Def: Having different types of teeth. Mammals have four different types of teeth: incisors, canines, premolars, and molars Sig: Because of heterdont dentition among primates, researches can use dental formula to compare primates against ancestors and group in phylogenic trees
Hominin
Def: Humans and their ancestors since the time of divergence from the common ancestor of humans, chimpanzees, and bonobos Sig: The gradual development of obligate bipedalism, for example, is a clear distinguisher of this taxonomic tribe
Opposable finger and toes
Def: Identification: fingers and toes that can touch the other digits, enabling a grasping ability Sig: humans have the longest opposable thumb, and therefore, the greatest opposability- part of a unique adaptation for the human hand. Important for "power" (good for wielding blunt objects) and "precision" grips (good for holding small objects) Many primates have opposable toes (humans do not), lost opposability in toes as we shifted from quadrupedalism to bipedalism
Hominoid
Def: In addition to humans, great apes (chimpanzees, bonobos, orgatans, gorillas) and lesser apes (gibbons) Sig: There is a diversity of locomotive tendencies in this category, ranging from suspensory brachiation and knuckle-walking to obligate bipedalism; shows the distinctiveness of the human locomotion.
Foramen magnum
Def: In the occipital bone, there is a distinctive "hole" that serves as the passage of the spinal cord to the brain (where the spine enters) Significance: Differences in the foramen magnum location (for example between ape/monkey located in back of the skull) might be attributable determiner of bipedalism. [Occipital for quadrupeds, have to do with adaptations Central for bipeds]
Cranial capacity
Def: It is a measure of the volume of the interior of the cranium (also called the braincase or brainpan or skull) of those vertebrates who have both a cranium and a brain. It is used as a rough measurement for the size of the brain. Significance: Homo sapiens perhaps have the 'largest' cranial capacity with enlarged brains to more effectively conduct: archeologists can therefore use cranial capacity to determine the relationship to modern humans in hominins
Orrorin tugensis
Def: Pre-australopithecine species, found in Kenya, about 6 mya with a noticeably long "femur neck" Sig: The discovered long "femur neck" is similar to later bipedal hominins, indicating some of the earliest evidence of bipedalism.
Arboreality
Def: Set of behaviors and morphological characteristics associated with tree-living Sig: In history of human evolution, our primate ancestors were arboreal before the hominini development of bipedalism, perhaps using brachiation locomotion.
Knapping
Def: Shaping a piece of stone by striking it so as to make stone tools or weapons or to give a flat-faced stone for building walls
anthropoid
Def: Suborder of the order Primates that refers to higher primates Sig: Group of species that is more closely related to humans in the order Primates, can be used to study relationships with other suborders and also within the suborder
Dental Arcade
Def: The dental arcade is the shape made by the rows of teeth in the upper jaw. Sig: Hominids gradually developed a C-shape arcade, rather than a U shape, and thus researches can compare fossils of dental arcade to determine relation to humans
Sahelanthropus tchadensis
Def: The earliest pre-austrslopithecine, find in Central Africa, around 7-6 mya. This species had more central location of foramen magnum, and primitive-ape like brain. Sig: The central location of foramen magnum suggests that this creature was possibly bipedal. The combination of ape-like (brain-size) and humanlike (bipedalism), and antiquity, means this is closest to the divergence of the common ancestor into apes and hominins.
Phylogeny
Def: The evolutionary relationships of a group of organisms Significance: Based on physical traits, genetics, and behavior, we can deduce evolutionary lineages and form phylogenic trees. For example, apes have sectorial complexes, whereas humans do not.
Core
Def: The larger piece of stone from which shards are broken off and used as tools. These tools are called flakes.
Cenozoic
Def: The most recent geological era. Dating from 65 million years ago to the present. Era in which mammals flourished. Began as the last dinosaur died at the end of the Mesazoic. Sig: Human primate ancestors occupied an ancestral arboreal niche that allowed traits like better vision and prehensile hands to develop
Dental comb
Def: When anterior teeth are tilted forward, creating a scraper. Sig: Among primates, this is especially useful for scraping and groomin fur. (Humans do not have dental combs and therefore cannot be categorized as gumivores, others might have this adaptation)
Sexual dimorphism
Def: a difference in a physical attributes between the males and females of a species. Sig: Sexual dimorphism is higher in societies where primate males compete for females (and tend to be larger and aggressive). Human sexual dimorphism could be low, according to the Reno theory, because early males were cooperative, not competitive.
Gumnivory
Def: a group of animals whose diet consists primarily of the gums and saps of trees. Sig: (GUESS) Can trace heterodont dentition in primates by looking at their "thoothcombs"
Prehensile
Def: adapted for seizing or grasping Sig: Our distant ancestors, early primates, probably developed prehensile limbs for arboreal mobility or grasping fruit/food.
Omnivory
Def: animals that have the capability to obtain chemical energy and nutrients from materials originating from plant and animal origin. Sig: trait that all primates share, part of the arboreal hypothesis that primates had an adaptation to an arboreal niche (would have led to omnivory). Studies of the omnivorous chimpanzee hunting can help shed light on human ancestors techniques for food acquisition and hunting
Mary Leakey
Def: anthropologist who searched for early human bones in the Great Rift Valley Sig: discovery of an Australopithecus skull in the Olduvai Gorge expanded the territory in which early hominins were known to have lived- added a new dimension to their variability and geographic distribution. Work laid the essential groundwork for our current understanding of the first humans and their place in evolution.
Louis Leakey
Def: anthropologist who searched for early human bones in the Great Rift Valley Sig: discovery of an Australopithecus skull in the Olduvai Gorge expanded the territory in which early hominins were known to have lived- added a new dimension to their variability and geographic distribution. Work laid the essential groundwork for our current understanding of the first humans and their place in evolution.
Pentadactyl
Def: having five digits on each hand or foot. Sig: Species that are pentadactyl can be understood that they all shared a common ancestor (ie birds, mammals, reptiles, etc.)
Lucy
Def: one of the most significant fossils; 40% complete skeleton of an adult female Australopithecus afarensis found in East Africa (in Ethiopia); one of the most complete skeletons dated before 100 kya; oldest potential ancestor for every known hominin species at the time of her discovery; Sig: Because of her similar skeletal features, solidified idea that walking bipedally was one of the key traits driving human evolution forward
R-selected species
Def: pecies that emphasize high growth rates, typically exploit less-crowded ecological niches, and produce many offspring, each of which has a relatively low probability of surviving to adulthood Sig: Humans are not an R-selected species, studying those that are allows us to compare and contrast inherited vs. derived traits
Monogamous (CHECK)
Def: refers to a social group that includes an adult male, an adult female, and their offspring Sig: one of the six main types of primate residence patterns, seen in gibbons, siamangs, and - shows our relationship with our primate cousins
K-selected species
Def: species whose populations fluctuate at or near the carrying capacity (K) of the environment in which they reside Significance: Primates, including humans, are k-selected species, with longer periods of development, smaller quantities of offspring, in order to compete most effectively for resources
Sexual selection
Def: the frequency of traits that change due to those traits' attractiveness to members of the opposite sex Significance: primary reproductive strategy of males is to physically compete for access to reproductively mature females → strong degree of natural selection in males to have large bodies and canines. This can help explain why certain traits have been passed down in the human lineage even to this day. Reto theory might contradict as early homini might have been cooperative, with pair-bonding neccesary for resource provisioning.
Hominid
Def: the group consisting of all modern and extinct Great Apes (that is, modern humans, chimpanzees, gorillas and orangutans plus all their immediate ancestors). Sig: Hominid was the traditional term to describe humans and immediate ancestry, but as genetic studies have linked us more closely to chimpanzees, the meaning of hominid has broadened.
Dental formula
Def: the numerical description of a species teeth, listing the number in one quadrant of the jaws of incisors, canines, premolars and molars Sig: Because in primates the primitive dental characteristics are retained (four tooth types, incisors, canines, premolars and molars). Anthropologists record each primate species' dental formula Also use this to compare against ancestors (dental formula of ancestor can help determine who it's currently related to) → allows us to group in phylogenies
Frugivory
Definition: A fruit eater. Seen in frugivores → Large protruding incisors for opening fruit and nuts; low, rounded cusp premolars and molars for grinding; thicker enamel (nuts, seeds); prefer ripe fruit and seeds discarded and undigested and must supplement their diet with other resources Significance: We trace the evolution of early primates largely based on teeth, and dentition adaptions to diets (like a frugivore) provide insight into ancestral tendencies.
Adducted Hallux
Definition: A non-opposable big-toe. Significance: As part of our evolution towards bipedalism and away from arboreality, humans adapted away from this trait to improve our distance walking.
Great African Rift Valley
Definition: A region in East Africa, with considerable early hominin sites, and volcanic activity that has permitted use of radiometric dating. Sig: This was the sight of the Leakey's discovery of a complete cranium, expanding the sites where early hominins were known to have lived.
Flake
Definition: A sharp, thin piece of rock that has been broken off a larger rock. Used to make sharp tools like scrapers, blades, and arrow heads.
Convergent eyes
Definition: Forward facing eyes Significance: Stereoscopic vision, better depth perception, and one of the shared derived-traits of primates (rely more on vision and less on smell), this was one of our ancestor' crucial trait to spot insects and prey within vegetation
Endocast
Definition: Fossilized impressions of the interior of crania Significance: They provide some idea of the relative size of brain lobes in the cranium, as well as their orientation to the rest of the brain, help comparing different primate and hominid species
Pan
Definition: Genus referring to chimpanzees, including bonobos Sig: our closest living relatives- by studying their behaviors and anatomy, we gain insight to how our ancestors behaved. Also sheds light on ancestral vs. derived traits in humans.
Lesser ape
Definition: Primates that live in Southeast Asia, example: Gibbons, skilled brachiators Sig: Relatively different evolutionary paths from Great Apes, with less cranial capacity/intelligence
Nocturnal
Definition: Refers to those organisms that are awake and active during the night. Sig: Color vision likely evolved as early primates moved from nocturnal adaptation to diurnal adaption.
Dinural
Definition: Refers to those organisms that normally are awake and active during the night Significance: Color vision likely evolved as early primates moved from nocturnal adaptation to diurnal adaption.
Bicondylar angle
Definition: The angle between the femur and the knee (thigh bone angels inward and positions knee at the midline of the body) Sig: Consistent with bipedalism, develops as one walks (infants don't have it); Unique to humans, and serves to place the knee and foot under the body's center of gravity during single support phase of gait --> could be used to determine if fossil was bipedal
Gorilla
Definition: This is the taxonomic genus that consists of the western and eastern gorilla (features: sexual dimorphism: herbivorous: polygamous: social organization) Significance: Aside from the Pan genus, the Gorilla genus is one of our closest living extant primate relatives, complete with social groups and similar skeletal structures.
Bipedalism
Facultive: Capable of walking or running on two legs but not the main mode of locomotion. Usually for only a short period. Obligate: Where bipedalism is assumed as the regular form of locomotion and there is no reasonable alternative (i.e. upright locomotion in humans)