Anthro 1 csus Exam 3

A shift to extractive foraging and hunting would favor

larger brain size and greater intelligence

Neanderthals and anatomically modern humans in the Middle East

lived side-by-side for thousands of years.

Kamoya Kimeu:

Fossil finder extraordinaire!

Oldowan Tools (Mode 1)

Hammer stone, core stone, flake

Australopithecus africanus (first australopithecine discovered) (2.8-2.4 mya) (448 cc (brain sz)) EQ (2.7)

History of Discovery • 1924 Raymond Dart discovered the first known "bipedal ape" Australopithecus africanus • He claimed it was the "missing link" between apes & people BipedalTraits: •Human-like shape of pelvis •Convergent big toe• Foramen magnumunder skull derived cranial traits shared with later species: smaller canines, bicuspid premolars & less prognathism • Taung, South Africa • child (tooth eruption) ('Taung Baby' or 'Taung Child') • deciduous canines small • ape-sized brain • brain stem position underneath skull (foramen magnum) Eventually Dart's claims about Australopithecus africanus were accepted, and his Taung Baby took its rightful place of honor as a member of our family and perhaps an early human ancestor. Raymond Dart argued that the Taung child was bipedal because it had a foramen magnum at the bottom of the cranium

Asian Archaics

Homo erectus and Homo heidelbergensis may have co-existed in East Asia. In Asia, Homo erectus persists until perhaps as late as 30,000 years in some places. Other forms of archaic Homo appear, but are hard to place in time or in the family tree. . . Flores, Indonesia

Mode 2 tools Acheulean (Lower Paleolithic)

Homo ergaster's tools • 1.6-1.4 mya Homo ergaster invented Acheulean handaxes • larger, more sophisticated, bifaces

First members of Homo (2.4-0.6 mya)

Homo habilis/rudolfensis •Similar to Australopiths, but with smaller cheek teeth & larger brains Homo ergaster / Homo erectus •human-like efficient bipedalism, tall with long legs, lower sexual dimorphism; and inhabited a broader range of habitats than earlier hominins

Homo Sapiens (1400 cc) (5.8 EQ)

Imagine you are a paleoanthropologist. You have found a fossil that dates to 45 kya in Europe and it has a cranial capacity of 1,400 cc, a chin, and is associated with Aurignacian tools. How would you classify this specimen? Imagine you are a paleoanthropologist. You have found a fossil that dates to 150 kya in Africa and it has a chin. How would you classify this specimen? HS has chin

Homo habilis (2.4-1.6mya)

Larger brain - about 630cc, EQ=3.6 Smaller cheek teeth - using tools to process food outside of mouth?

Blades are classified in what kind of tool kits?

Mode 4

Sivapithecus.

Modern orangutans may have evolved from

Potassium Argon Dating

Potassium-40 is said to be unstable because it changes to argon-40 over time. Potassium-argon dating is used for dating volcanic rocks

Early hominins were bipedal animals with brains about the size of a typical ape brain.

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Evidence that early hominins were bipedal includes a set of fossilized footprints at Laetoli in Tanzania

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Evolutionary dwarfism occurs when animal populations are confined on islands with few predators and limited supplies of food.

T

It is likely that New World monkeys are descended from an African ancestor who rafted from that continent

T

Some researchers argue that there was no behavioral revolution in Europe associated with modern humans.

T

The spread of woodland and savanna led to the evolution of the first hominins about 6 mya

T

Upper Paleolithic people developed more complex forms of shelter and clothing than did Neanderthals. ____

T

Miocene epoch.

The first hominoids evolved in

Eocene epoch 54MYA

The first true primates occurred in

teeth of A. afarensis are intermediate between apes and humans in several ways.

The upper canines of chimpanzees wear on the sides. • Human canines wear on the tip (apical wear). • The canines of A. afarensis show wear on the sides and on the tip. The shape of the first lower premolar of A. afarensis is intermediate between the unicuspid chimpanzee's premolar and a human's bicuspid premolar.

Late Pleistocene Population Expansion

Unlike Neanderthals, H. sapiens learned to live in the severe cold of the far north - into SW Siberia perhaps as early as 40 kya, and down to Japan by at least 35-30 kya. At certain periods during the last 50,000 years, a corridor was open from Asia into North America. At other times the Bering land bridge existed, but the corridor was closed. Siberians migrated to North America sometime during the open periods. • The eastern Siberians followed herds of antelope and yak across the Bering land bridge, probably around 14,000 ya. • Then south between the two continental ice sheets. • "When" is controversial. Certainly people were there 12kya. It is possible that they migrated earlier (many claims). • There is a site in North Brazil from 32,000 years ago that may have evidence of anatomically modern people. • Site at Monte Verde, Chile dated to 12,500 years ago. Most skeptics accept Monte Verde. The first people to arrive in North America were big game hunters who may have followed herds moving across the Bering land bridge and then to the South.

Changes associated with bipedalism

What are the specific bipedal adaptations in the following body parts? (see Lecture 13) •Pelvis •Legs •Feet •Spine •Foramen magnum

Derived features of anatomically modern humans included

a rounded skull

atlatl:

a spear-thrower that increases force and distance

example of modern human behavior?

art

The first primates similar to modern monkeys appeared

at Fayum in Egypt.

Characteristics that make a hominoid into a hominin include

bipedalism.

A. afarensis and A. africanus

both had ape-sized brains.

The lifeways of Neanderthals probably included

burial of the dead. hunting large game.

With food sharing comes increased paternal care. Therefore, what other characteristic do we expect to evolve with this pair of traits?

decreased sexual dimorphism

Australopithecus afarensis, a hominin dating from the Pliocene (434 cc) (2.5 EQ)

found at Laetoli in Tanzania & the location of Hadar in Ethiopia in beds dating between (3.4 & 3.0 mya) Features showing that Australopithecus afarensis is a hominin include bipedalism. Footprints were distinctly those of a biped with a convergent big toe and human-like pattern of walking A. afarensis was bipedal :angled femur • knee surface flattened and broadened for stability • pelvic blade shortened • big toe convergent not exactly like modern people. They had short legs and long, curved toes and fingers. They also had a cone-shaped chest. They probably still climbed a lot and did not walk with the same striding gait of modern people. sexually dimorphic in body size, like the great apes today, although not as extreme as gorillas and orangutans. Male/Female = 1.6 teeth of A. afarensis are intermediate between apes and humans in several ways.

Bipedalism may have evolved because it allowed hominins to

harvest food from small trees

Human Cultural Revolution

innovations included long-distance transportation of raw materials, decoration and art.

Homo ergaster (1.8 ~ 0.6mya)

"Turkana Boy" (aka "The Strapping Youth") - Nearly complete skeleton • Dated to 1.5 mya • 12-year-old male, 5'4" tall • Infer adulthood: 6'1" tall, 150 lb • Inferred adult brain size: 900 cc •Tall •Long legs •Much more humanlike proportions than previous hominins Earlier hominins • short legs • apparently restricted to wooded areas • moved short distances on the ground ‣ H. ergaster • longer legs • entire body more efficient, human-like walking and endurance running Shared features with earlier hominins: ‣ Supraorbital sulcus ‣ Supraorbital torus ‣ No chin ‣ Receding forehead Many derived features: ‣ **Big brain (~900 cc) ‣ Smaller cheek teeth ‣ Higher skull, less prognathic ‣ Occipital torus (not in earlier specimens or in modern humans) By 1.7 mya Homo ergaster became the first hominin to leave Africa and reach Eurasia

Ardipithecus ramidus

(5.6 - 4.4 mya) - what we would expect the common ancestor of African apes and humans to look like. It is fairly ape-like except for a few derived traits shared with later hominins. -Less projecting and more "incisiform" canines are two derived traits shared by Ardipithecus and later hominins. - a non-weight bearing elbow that may imply bipedalism. discovery of Ardipithecus ramidus in a forested environment negates some of the savanna hypotheses. It suggests that the first steps of hominin evolution occurred, not on the savanna, but in wooded habitats. The diet of A. ramidus was probably similar to that of modern chimps.

Homo ergaster

- appeared in the fossil record about 1.8 MYA -Homo ergaster possessed some ancestral characteristics of earlier hominins, including large browridges

Piltdown Man

-"Discovered" in 1912 in England by Charles Dawson -Showed that "the brain led the way" in human evolution. -"Proved" earliest hominin was English! (not African) The Piltdown find was proclaimed genuine by several British scientists of the day: Arthur Smith Woodward, Arthur Keith and Grafton Elliot Smith. -In fact, it was all an elaborate hoax. The bones were those of a 6oo yearold human skull and a modern orangutan mandible, which had been filed and chemically aged to resemble an authentic find.

Neanderthals

-had midfacial prognathism. -were resistant to many diseases Derived features: large brains Mousterian tools In 1856 a famous discovery was made at a place called Neanderthal (now spelled Neandertal) History: Discoveries that put Neanderthal on the map • In 1856 German quarry workers uncovered a skullcap and some postcranial bones of a Neanderthal in Feldhofer Cave of the Neander Valley. - This discovery was highly publicized, mostly because of the current hot debates over human evolution. - Only three years later Darwin published On the Origin of Species; in 1863, Huxley published Man's Place in Nature. • Of those that described the skullcap from the Neander Valley, some thought it was rather funny looking (heavy browridges, etc.). • One very famous pathologist concluded that the person had been quite diseased before they died, and perhaps had rickets. Neanderthals were originally described as brutish cavemen. Neanderthal fossils have been found in Europe and the Middle East. They occupied these regions from about 150 to 35 kya. Homo neanderthalensis had a distinct anatomy, especially its mid-facial prognathism, occipital bun, retromolar gap, and an extremely robust and powerful body. Mid-Facial Prognathism Neanderthal Homo sapiens The occipital bun is characteristic of Neanderthals. The word "bun" refers to the rounded bulge on the back of the head in about the same location that modern people sometimes wear a bun in their hair. Neanderthal H. sapiens Compare traits: •Chin •Browridge •Occipital region •Midfacial prognathism •Forehead Retro molar gap • Above: H. neanderthalensis has the gap • Below: H. sapiens does not have a retro molar gap. • Large neck muscle and ligament attachment sites on their spine • Thick ribs • Barrel-chested • Thick, large limbs (extra cortical bone) They had powerful & robust bodies: Neanderthal Human Femurs: Neanderthal hands • Their hands are adapted for powerful gripping: - The distal phalanx of the thumb is about as long as the proximal phalanx. - The apical tufts are larger and rounder than in early modern humans. Comparing Homo neanderthalensis and Homo sapiens skeletons 1) Neanderthal 2) modern human Neanderthal modern human Neanderthal injuries suggest a way of life. Neanderthals risking injury The Neanderthals made more complex tools than their ancestors. • Oldowan and Acheulean cultures are called Lower Paleolithic. • The Neanderthals made Middle Paleolithic tools (Mousterian Culture)

Which of the following bones provide evidence that a fossil animal was bipedal?

-the pelvis -the foot

Ardipithecus ramidus differs from Australopithecus in that

it lived in more densely forested environments

Bipedalism may have evolved because it allowed hominins to

keep cool in savanna environments

The Increase in Foraging Complexity

1)Human foraging relies more on foods that require skill to obtain -The need for increased foraging skill leads to division of labor -Accomplished hunters and grandmothers over-produce and supplement diets of others -Division of labor implies substantial flow of food between sexes and age groups 2)Difficult ways of obtaining high quality food sources selected for:- Larger brains (need to be clever!) - Long periods of juvenile development • Time for brains to grow (cannot grow big in womb) • Time to learn important foraging skills - Specialization favored a division of labor, which favored sharing and cooperation as a form of "social insurance" - More male parental investment (provisioning offspring) means less male-male competition and therefore, reduced sexual dimorphism Think about how all these factors are connected!

Anatomical changes associated with bipedalism

1)curved spinal column brings body weight over feet 2)differently shaped pelvis helps position body weight & rearranges muscles 3)thigh bone (femur) angles inward & positions the knee at the mid-line of the body 4)bigger knee joints (body weight distributed on 2 instead of 4 legs) 5)non-grasping big toe in line with the other toes → ability to "toe-off" **arches & ligaments in hominin feet act as a shock absorbers when walking or running

Lucy (Found Hador, Ethiopia a. afarensis)(3.2 mya)

1975 they found the "First Family" with at least 13 individuals. A. afarensis was bipedal :angled femur • knee surface flattened and broadened for stability • pelvic blade shortened • big toe convergent

Anatomically modern humans appeared between

200,000 and 100,000 years ago.

Modern humans are thought to have migrated from Africa and spread throughout the world about

60 KYA

____Absence of a tail____ is a derived feature that Proconsul shares with living apes and humans.

Absence of a tail

The oldest anatomically modern human fossils are found in

Africa.

Australopithecines

Bipedal primates

Mode 4 Mode 4: Upper Paleolithic

Blade tools

Homo heidelbergensis (600-100kya)

Distinct from H. erectus, but still retaining many erectus-like features. Traits shared withHomo erectus: 1) Occipital torus 2) Supraorbital torus 3) Receding forehead But H. heidelbergensis is distinct from Homo erectus in having brains in the modern human range (1000 cc+). Geographic distribution of H. heidelbergensis fossils Asia, Africa, & Europe In Europe, H. heidelbergensis evolves into H. neanderthalensis. The Neanderthals dominate Europe and West Asia until they go extinct between 45 & 30,000 years ago.

Late Pleistocene Technology

Examples of decorative carvings associated with Upper Paleolithic cultures. Decorated items like this were often atlatls. Upper Paleolithic cave painting from Europe. Paintings of people and animals appear often in sites of Upper Paleolithic culture. Among the earliest distinctive Upper Paleolithic cultures was the Clovis culture represented by these large, broad projectile points (spear heads).

. Neanderthals were adapted for a harsh, hot, and dry climate

F

A sagittal crest is associated with larger brain size.

F

Australopithecus afarensis lived in East Asia.

F

Bipedalism can be easily detected in the fossil record because only bipeds have a foramen magnum

F

Modern human cranial capacity is larger than that of the other hominins of the Pleistocene including Neanderthals.

F

Modern humans appeared about 500,000 years ago

F

The Laetoli footprints indicate that large brain size evolved before bipedality in hominins.

F

The earliest hominins had large brain-to-body-size ratios.

F

The function of the sagittal keel in H. erectus is the same as the sagittal crest in the "robusts".

F

The only Miocene hominoid that can be linked with a modern species is Kenyapithecus, which is probably ancestral to the gorilla.

F

bicondylar angle (angle of the femur)

marker of bipedalism

morphology of A. afarensis illustrates

mosaic nature of hominin evolution: Head of an ape, body of a human

A fossil specimen with huge eye sockets. The animal was most likely

notcturnal

The first lower premolar of chimpanzees has _____1_____, the first lower premolar of humans has ______2____, and Australopithecus afarensis had ___Large cusp_______.

one cusp; two cusps; a small and a large cusp

Chimpanzees (395 cc) 2.0 EQ

primarily include collected foods in their diet

Australopithecus africanus shares which of the following traits with humans?

reduced canines

Mode 1/ Oldowan/ (Lower Paleolithic)

refers to the method used to make Oldowan stone tools.

The most likely explanation for the evolution of modern human behavior is that

the components of modern human behavior and technology gradually evolved in Africa along with modern human morphology over a period of about 200,000 years.

Upper Paleolithic technology included

the introduction of hand axes the introduction of new raw materials such as bone Bone, antler, and teeth were used to construct tools

Homo floresiensis

the most widely supported explanation for the small body size and mixture of ancestral and derived traits of Homo floresiensis: H. floresiensis is a result of evolutionary dwarfism • Discovered in 2003 • Small body (3.5 feet) • Small brain (380 cc) • Small teeth • Strong, arching brow ridges • Perhaps as old as 18,000 years or more and persisting until about 13,000 years ago. • Possibly died out as a result of volcanic eruptions. • Probably evolved from Homo erectus. • Likely underwent the process of "insular dwarfing" common among animals living on small isolated islands.

Continental drift is

the movement of continents.

Acheulean tools

used over a broad geographical area and a very long time period Acheulean dominated 1.4 mya - 300kya Stasis in handaxe tool technology for 1 million years! Mode 2 methods.

Plesiadapiforms

were not primates but rather a related group

The Human Revolution? Maybe Not.

• "Upper Paleolithic" (UP) in Europe • "Middle Stone Age" (MSA) and "Late Stone Age" (LSA) in Africa • Two views: 1) 'modern human behavior' arose suddenly about 50 kya in Europe and Africa OR 2) 'modern human behavior' was evolving gradually over a long period of time (250-60 kya) in Africa The Human Revolution? Maybe Not. • Most people now accept #2 as the most reasonable based on the archeological evidence. • What seems like sudden & revolutionary change in Europe was actually due to the rapid replacement of Neanderthals by more technologically and culturally advanced African immigrants. • There are vastly more archeological sites that have been excavated in Europe than in Africa, so we know much more about the people who lived there.

Fire use?

• A few archaeological sites appear to preserve evidence for controlled use of fire by early Homo (e.g., East Africa at 1.6 mya???) • difficult to rule out natural burning • Zoukoudian (China) ~500 kya:burnt bones and stones & what appear to be layers of ash • But, chemical analyses have failed to find wood ash or charcoal in the layers • After ~130 kya: abundant evidence of simple fireplaces • e.g., Sterkfontein in South Africa • most fire evidence from caves • After 130 kya: many archaeological sites in caves • Before 130 kya: many sites in open-air • May explain the absence of earlier clear evidence for fire

emergence of the genus Homo

• Defined by increased brain size • Associated with behavioral innovations: - Food-getting strategies - Division of labor & food sharing - Tool use

Cro Magnon

• Discovered in 1868 near Les Eyzie in S.W. France at the Cro Magnon rock shelter. • Associated with lions, reindeer, and mammoth. • Mode 4 "blade" tools (in this case, Aurignacian). Upper Paleolithic ("UP") • Five anatomically modern people (now dated to 30,000 years ago) Robust but modern:• Vertical forehead • High vault bones • Parallel sided skull bones • Rounded occipital • Very slight brow ridges • Flat faces tucked under their brains • Prominent chins

Attributes of Fully Modern Human Behavior

• Diversity and standardization of artifact types • Rapid increase in rate of change in artifact types over time and space • Earliest evidence of shaped bone, ivory, shell, etc. • Earliest evidence of composite tools • Earliest undeniable art • Earliest evidence for organized camp floors • Oldest evidence of transport of raw materials over long distances (100's of kilometers) • Earliest secure evidence for ceremony and ritual • Evidence of ability to live in extreme cold climate • Rapid increase in population density • Fishing, and other evidence of advances in acquisition of food energy

Origin of Homo

• First discoveries of genus Homo in Tanzania at Olduvai Gorge • Dating ~2.4 - 1.6 mya (Pleistocene) • Contemporaneous with the 'robusts

Homo erectus (~1 - 0.1mya)

• Fossils found in: Indonesia China First discovered in Java in 1891 Very difficult to date, lots of disagreement Larger, shelf-like brow ridges Angled occipital region with torus Sagittal keel (function unknown) Homo erectus' tools: Eastern Asia: less elaborate, "chopper/chopping" tools • Stone tools used to fashion better, more sophisticated bamboo tools? Homo erectus in Indonesia and China persisted until perhaps ~ 30 kya Little increase in technological innovation, or behavioral flexibility

Out-of-Africa

• Homo ergaster left Africa (1 st migration 1.2-1.8mya) In Asia → evolved into H. erectus (and possibly H. floresiensis) In Europe and Middle East → evolved into H. heidelbergensis, and then H. neanderthalensis • The H. ergaster (heidelbergensis?) who stayed behind in Africa during the 1st migration evolved into H. sapiens, who then left Africa again (2nd migration 60kya), replacing all the other hominins in Europe, Middle East, and Asia • All modern humans are descended from the Homo sapiens of the 2 nd migration out of Africa

Middle Paleolithic Mode 3: Mousterian (Middle Paleolithic)

• Mousterian tools, associated with H. neanderthalensis in Europe. • "Flake" tools • Broad, short pieces struck from a core • "Retouched" flakes • Mode 3

Homo sapiens Tools

• New materials: sharpened bone, ivory and antlers, in addition to stone • Mode 4 (blade tools) • They also made some composite tools: tools made of two or more different materials (i.e. blades hafted onto a wooden handle)

Primate Origins

• Paleocene (65 mya) • Eocene (54 mya) • Oligocene (34 mya) • Miocene (23 mya) • Plesiadapids - primate-like, but not primates • Early prosimians - Adapids - lemur/loris-like - Omomyids - tarsier-like • Early anthropoids - New World monkeys???? - Aegyptopithecus? (monkey?) • Early hominoids - Proconsul ? (monkey or ape?) - Oreopithecus - Sivapithecus - Gigantopithecus

"Out of Africa" vs "Multiregionality"

• Two competing hypotheses regarding the emergence of anatomically modern H. sapiens: • Out of Africa - Anatomically modern H. sapiens evolved from the archaic Homo population in Africa - Spread throughout Europe and Asia replacing all other archaic Homo species, including the Neanderthals • Multiregionality - Anatomically modern H. sapiens evolved simultaneously from archaic Homo populations throughout Africa, Europe and Asia - Constant gene flow between populations essentially made all archaics a single population (with the exception of the Neanderthals) • The two hypotheses agree on the following: - First Homo out of Africa was H. ergaster (erectus) about 1.7 mya - Neanderthals are not ancestral to anatomically modern H. sapiens • The two hypotheses disagree on the following: - Origin of anatomically modern H. sapiens - Amount of gene flow between populations - Second migration out of Africa Most scientists now agree that the Out of Africa hypothesis is the best interpretation of the fossil (and genetic) evidence.

Early hominins (~6-2 mya) Ardipithecus ramidus, Australopithecus afarensis, A. africanus

•Bipedal on the ground, but retained arboreal adaptations •Jaws & teeth were intermediate between chimps & humans •Brain size similar to apes

Hominins with unique adaptations (~3-1 mya) A. aethiopicus, Paranthropus boisei, P. robustus = "the robusts"

•Bipedal on the ground, but still sometimes arboreal •Had large cheek teeth & skulls adapted to heavy chewing of tough vegetable foods

"The Robusts" Australopithecus aethiopicus (2.7-2.3 mya) eastern Africa Paranthropus boisei (2.3-1.4 mya)eastern Africa Paranthropus robustus (1.8-1.0 mya) South Africa

•Living around the same time as the more gracile A. africanus •Skulls probably adapted to a coarse vegetarian diet skull structures specialized for heavy chewing. -Evidence that the "robusts" ate hard foods includes flared zygomatics (i.e. cheekbones). Imagine you have found a skull with an ape-size brain, sagittal crest, very large back teeth, and large cheekbones. Based on this information, this is most likely a specimen of

The Pleistocene: First members of the genus Homo Homo habilis & Homo rudolfensis

•Most people classify them as early Homo species but some argue they should be classified as Australopithecus (or even Kenyanthropus rudolfensis)

Trends in hominin evolution

•Smaller and flatter faces •Rounder and larger brain cases •Less robusticity (zygomatics, browridges, etc.) •Smaller teeth •Taller, with longer limbs •Less sexual dimorphism •Reduced prognathism •Brain expansion •Higher cranial vault •More rounded skull •Less receding chin region •More flexed skull base

Anatomically modern Homo sapiens

•These are the earliest fossils attributed to Homo sapiens. •Indicates that anatomically modern people originated in Africa about 100-200 kya. In West Asia, a.m. H.s. appear perhaps as early as 100kya at a cave site called Qafzeh. -In China and Indonesia even later, though dating is uncertain at these sites. Probably about 30kya.