NCEA Level 3 Biology - Human Evolution (3.7)

Biological evolution

Transmission of genetic factors inherited from parents

Cultural evolution

Transmission of ideas, beliefs and knowledge by learning from other members of the group

Human evolution

Progressive biological and cultural change and development from our hominin ancestors to modern humans

Primates

The large group of mammals to which humans, the other great apes and monkeys belong

Hominid

The family that contains all modern great apes, extinct great apes, and modern humans

Hominins

The group consisting of all modern humans, extinct human species, and all immediate human ancestors

Quadrupedal

Habitually walks on four limbs

Bipedalism

Habitually walking upright, on two legs

Foramen magnum

Hole underneath of skull for spinal cord

Sagittal crest

Supports large jaw muscles in apes

Nuchal crest

Supports muscles that hold the head up in apes

Brow ridges

Support the skull during the mechanical stress of chewing in apes

Zygomatic arch

Cheek bone in apes

1400

Average cranial volume of humans (cm3)

450

Cranial volume in apes (cm3)

Diastema

Space on upper tooth row in apes for larger lower canine tooth to fit into

Paretial lobes

Part of brain for integrating sensory information, manipulation of objects

Temporal lobes

Part of brain for hearing, sight, speech and memory

Broca's area

Area of brain which organises sound into sequences (speech)

Wernicke's area

Area of brain which interprets sound

Frontal lobes

Part of brain where cerebral cortex is much more convulted in humans than in apes

Cerebral cortex

Part of brain which is the folded outer layer for thinking and foresight

Cerebellum

Part of brain for balance, muscle co ordination, fine finger movements

A. anamensis

Ape like face and teeth, low forehead, brow ridges, no chin, large canines, diastema, thick enamel on molars, U-shaped jaw as in apes, probably bipedal

A. afarensis

Known as 'Lucy'; face and cranium ape like, Tooth row v-shaped as in humans. Bipedal (foramen magnum more central at base of skull). Sexual dimorphism

A. africanus

Known as 'Taung child'; Face less ape-like (higher forehead, smaller brow ridges), smaller canines, no diastema, large molars, tooth row v-shaped, some sexual dimorphism

P. robustus

Probably not an ancestor; Large sagittal crest, brow ridges, no forehead, small canines, large grinding molars, lower jaw and zygomatic arch. Tough plant diet. Cranial volume 530 cm3.

P. boisei

Similar to P. robustus, with flatter face and nuchal crest

H. habilis

'Handy man'; Oldowan stone tools, complex sounds, co-operative hunting. Brow ridges, small jaw and teeth, tooth row v-shaped. Cranial volume 500-800 cm3, rounded cranium with Broca's area

H. erectus

Used fire, primitive speech, acheulean stone tools, huts for shelter. Vertical face, sagittal 'keel', large brow ridges, small nasal bone, projecting nose. Broca's and Wernicke's areas present, rounded cranium (750-1250 cm3)

Archaic H. sapiens

Acheulean stone tools, Good speech and language ability. Modern skull features, brow ridges. Rounded cranium (1100-1300 cm3). Well developed Broca's and Wernicke's area.

H. neanderthalensis

Not likely ancestors. Mousterian stone tools. Cared for injured and aged. Buried dead, wore clothing. Low, sloping forehead large brow ridge, occipital 'bun' at back for neck muscle attachment, receding chin, nose, cranial volume 1200-1750 cm3. Limb bones thick and strong (cold adapted).

H. sapiens

Upper paleolithic stone tools. Art forms. Spiritual awareness. High forehead, no brow ridges, prominent chin, nose, small teeth in v-shaped jaw, cranial volume 1200-1700cm3. Limb bones fine.

Oldowan tools

Pebbles with flakes knocked off one side; simple choppers, hammers and digger; sharp flakes which came off used as knives. Scavenged kills more easily processed, tough plant food crushed or cut up. Used by H. habilis (and H. erectus)

Acheulean tools

More complex, bi-facial, flake tools with symmetrical tear-drop, oval or disc shape, made for more specific purposes (eg. hand axe for chopping). Long time to make, up to 65 blows per tool. Used by H. erectus.

Mousterian tools

More sophisticated and finely worked; scrapers, spear tips, axe heads. Edges re-sharpened, attached to other materials for more accurate handling. Required skill and time to make; techniques taught and learnt. Used by H. neanderthalensis and early H. sapiens

Upper paleolithic tools

Tool making techniques refined, flakes had most edges shaped for cutting, variety of specialised tools for range of uses - spear and arrow heads, scrapers. Many bound to bone or wood (spears and arrows). Materials such as bone and antlers used, carved into needles, fish hooks, etc. Used by H. neanderthalensis and H. sapiens.

Fire

Earliest record 1.5 mya, used for cooking, exploiting new habitats, avoiding predators, improved hunting, and for light

Multiregional theory

Populations largely isolated with some interbreeding, so evolved in parallel to become species we are today with distinct features in regional races. Location of H. erectus in many regions supports theory.

Out of Africa theory

African population evolved into modern humans which moved out of Africa about 200 000 ya, replacing regional populations of H. erectus as they went.