Bio Human Evolution

Abstract thought

Definition

Using the forebrain to think of ideas beyond the obvious. For example,

creating creation myths.

Acheulian

Tool culture of Homo erectus and archaic Homo sapiens. Tear drop shaped, bi-

faced hand axe used for chopping and scraping, and flatter, blade-line

'cleavers'. Required skill to make and many more blows than Oldowan.

Agriculture

The domestication of animals and crop plants for food.

Ape

Knuckle walkers. Includes the orangutan, gorillas and chimpanzees. Have a

large brain and no tail, but are not bipedal like humans.

Arboreal

Species that mostly inhabit trees rather than the ground.

Arched foot

Found in bipeds to absorb the shock forces produced by upright locomotion.

Australopithecine

Group of extinct bipedal hominins ancestral to H. sapiens. For example,

A. anamensis, afarensis, africanus.

Biological

evolution

Changes in the genetic information of a population passed down from parent

to offspring through many generations.

Bipedalism

Locomotion where most of the motion involves only two legs.

Brachiating

Locomotion of primates that are arboreal, where arms are used to swing from

branch to branch. Used by most apes.

Broca area

Part of brain used in speech production.

Brow ridge

Area of skull above the eyes that protrudes. Larger in early hominins.

Calcaneus

Enlarged heel bone found in bipedal hominins.

Condyle

Buttress of bone on the base of the femur. Hominins have this on the outer

base, whereas apes have it on the inner base.

Cranium

The dome of the skull houses and protects the brain and is used to assess the

brain volume and shape of different hominins, allowing for inference about

intelligence. It is expressed in cm 3 .

Cultural evolution

Evolution where culture, such as clothing, language, music, tool making and

religion, is passed on through teaching. Much faster than biological evolution.

Diastema

Gap in jaw between canines and incisors to allow space for large canines to

fit.

Dogs

The first animal to be domesticated (from wolves) at least 12,000 years ago.

Domestication

Refers to the taming and management of livestock and plants. Including,

among others, cows, sheep, dogs, and wheat.

Evolution

Gradual change in the genetic code of populations

Extant

Species with members still living.

Extinct

Species with no living members.

Foramen magnum

Hole at the base of the skull for the spinal cord to pass through. A position

further forward under the skull is used to identify bipedalism.

Hominid

Family of species that includes apes and humans.

Homo erectus

Tall, strong hominin, first out of Africa, first to tame fire and use huts for

shelter.

Homo habilis

"Handy man." The first hominin found to use simple stone tools known as the

Oldowan tool culture.

Homo

heidelbergensis

These humans evolved in Africa, but some populations migrated into Europe.

They lived and worked in co-operative groups, hunted large animals and

made a variety of Acheulian tools.

Homo

neanderthalensis

Adapted for ice ages in Europe, it was stocky with a large brain. First to be

found to care for the injured, bury the dead and wear clothing. Mousterian

tool culture.

Homo sapiens

Includes humans today and close ancestors starting from 250,000 years ago.

Used upper Palaeolithic tool culture. Produced art, jewellery and music. Had

spiritual awareness. Also known as Cro-Magnon man in France.

Hunter-gatherers

Populations that get food by using a combination of hunting, fishing, and

foraging. Most likely nomadic.

Land bridges

Land formations that connect two or more landmasses,

facilitating the migration of flora and fauna between regions that are now

separated by water.

Mammals

Endothermic, vertebrate animal of a class that is distinguished by the

possession of hair or fur, females that secrete milk for young, and (typically)

the birth of live young.

Mitochondrial DNA

Circular DNA found in the mitochondria. Passed down through the maternal

line. Does not undergo crossing-over. Has a relatively constant mutation rate

and no proofreading. It can be used to compare the relatedness of species.

Mousterian

Tool culture associated with H. neanderthalensis and early H. sapiens. that

were made using the Lavellois' technique. They required skill to make, using

many more blows than Acheulian. Includes scrapers, spear tips and axe heads.

Used stone and flint.

Multiregional

hypothesis

A dispersal hypothesis which considers that small groups of H. erectus

migrated out of Africa around one million years ago, settled, remained

isolated and evolved in parallel with each other. The groups periodically

interbred to become the different tribes of H. sapiens we have today.

Neolithic

New Stone Age with the domestication of animals and plants.

Nuchal crest

A bony protuberance from the base of the skull at the back to support large

neck muscles. Smaller in humans due to bipedalism.

Oldowan

Tool culture associated with H. habilis where pebbles with flakes off one edge

and which took only a few blows to make. Includes simple choppers,

hammers and could be used as diggers.

Palaeolithic

Old Stone Age. Lasted approximately 2.5 million years, during which primitive

stone tools were used.

Paranthropus

Genus of vegetarian hominins includes P. aethiopicus, robustus and boisei.

Now considered a parallel branch to the ancestors of H. sapiens.

Power grip

Used by early hominins and when the hand is clamped to cup the tool, and

the thumb applies pressure.

Precision grip

The ability to perform precise movements by manipulating small objects, as

the thumb is directly opposable to other fingers.

Out of Africa

hypothesis

Also known as the Replacement Theory. Suggests there were waves of

migration out of Africa starting at one million years ago with H. erectus. These

groups of H. erectus evolved into different Homo species. H. sapiens evolved

in Africa about 250,000 years ago from H. erectus and migrated out of Africa

around 60-90,000 years ago, replacing all other hominins as they went.

Primates

Group of mammals to which humans, apes and monkeys belong. Have nails

instead of claws and a large brain relative to body size.

Prognathism

A protruding muzzle. A characteristic of early hominins and apes.

Quern

A grinding stone dated from approximately 17,000 years ago, used to grind

wheat and other grains into flour.

Sagittal crest

The bony projection on the top of the skull that is the attachment point of

large chewing muscles, usually found in primates with a herbivorous diet.

Selection pressures

Environmental factors that affect the fitness and survival of individuals within

a population and changing allele frequencies. For example, resource scarcity,

predation, or environmental pressures.

Sexual dimorphism

The male and female of a species are visibly phenotypically different. For

example, in many bird species, the male has bright feathers, whereas the

female has plain, camouflaging feathers.

Thermoregulation

The process of keeping a constant body temperature. For example, sweating

or shivering.

Upper Palaeolithic

Tool culture associated with H. sapiens and Neanderthals. Includes tools such

as arrows, spears, and scrapers. They were more refined and specialised, took

more time to make and had many more uses. Made from more materials than

just stone, including bone and wood.

Valgus angle

The carrying angle between the femur and the hip joint is less than 90

degrees, which indicates the hominin was bipedal. Places the centre of gravity

of the torso over the knee joints when standing.

Wernicke area

Area of the brain associated with recognising and decoding speech.

Y-chromosome

A nuclear chromosome passed down through the male line. Does not undergo

crossing-over. It can be used to compare the relatedness of extant species

and extinct species.

Zygomatic arch

The cheekbone. Allows the muscles for chewing to pass under it and attach to

the sagittal crest.