NCEA 91606 Human Evolution - Day 1 Vocabulary

Practice vocabulary flashcards covering anatomical trends, skeletal adaptations for bipedalism, stone tool technologies, and prehistoric art.

Cranial capacity

The volume of the braincase, used as an approximate measure of brain size.

Foramen magnum

The large opening at the base of the skull where the spinal cord passes through.

Prognathism

The degree to which the jaws or face project forward.

Bipedalism

Locomation that walks primarily on two legs.

Bipedal pelvis

A pelvis structure that evolved to be shorter, broader, and more bowl-shaped to provide attachment and positioning for muscles involved in stabilizing the body during upright walking.

Valgus angle

A pronounced inward angle of the femur that brings the knees closer to the body's midline, helping maintain balance and efficient upright walking.

S-shaped spine

A pronounced spinal curvature that helps position the upper body over the pelvis and absorb forces during upright walking.

Thermoregulation (in bipedalism)

A process of temperature control where an upright body presents less surface area directly exposed to overhead sunlight and exposes more of the body to moving air, reducing heat gain.

Oldowan technology

An early stone-tool technology appearing about $2.6\,\text{million}$ years ago, consisting of simple cores and sharp flakes produced by striking stone with a hammerstone. Early Homo, including H. habilis, is often associated with these tools, but the exact maker of the earliest tools is uncertain.

Acheulean handaxe

A deliberately shaped, symmetrical, teardrop-shaped and bifacially worked stone tool appearing about 1.7million years ago, strongly associated with Homo erectus.

Levallois technique

A stone-tool technique where a core is deliberately prepared to produce a flake of a planned size and shape. It demonstrates careful planning and control in tool manufacture.

Mousterian industry

A stone-tool technology primarily associated with Neanderthals (and some early modern humans), used broadly from around $300,000$ to $30,000$ years ago.

Ochre

A natural mineral pigment commonly used in prehistoric art to produce red, yellow, and brown colours.

Pigment spraying/blowing

A technique where pigment is blown through the mouth onto a surface to create soft edges, textures, or stenciled shape

Engraving

A deliberate design or pattern scratched or carved into a surface.

Give three hominins in chronological order showing increasing cranial capacity.

Answer: Australopithecus → Homo habilis → Homo erectus. Approximate averages: ~450 cm³ → ~600 cm³ → ~900cm³.

What was the approximate cranial capacity of Homo sapiens?

Answer: About 1,300 cm³, although there is considerable variation.

Is increasing brain size a perfectly linear trend?

No. Different hominin species had overlapping and sometimes unusual brain sizes, so it is better described as an overall increase with variation.

How did the position of the foramen magnum change during human evolution?

It became positioned more underneath/centrally beneath the skull rather than toward the back.

What does the position of the foramen magnum tell us about locomotion?

A more underneath/central position indicates that the head was balanced on top of a more upright vertebral column, supporting bipedalism.

Where is the foramen magnum generally positioned in quadrupedal apes?

More toward the back (posterior) of the skull.

What happened to jaw size during human evolution?

The jaws generally became smaller and less robust.

What happened to tooth size?

Teeth generally became smaller, particularly the canine teeth.

What happened to prognathism during human evolution?

The face became less prognathic, meaning it projected less forward

What happened to the human face as brain size increased?

The face generally became smaller and flatter, with reduced jaw projection.

Why might jaws and teeth have become smaller?

Hominins increasingly used tools and cooking/food processing, which made food easier to chew and reduced the need for large jaws and teeth.

How could cooking have affected dentition?

Cooking softens food and makes it easier to digest, reducing the mechanical demands placed on the teeth and jaws.

Why shouldn't we say that cooking alone caused smaller jaws?

Human evolution was influenced by many different factors, including slection pressures and fossils alone cannot always tell us exactly why a anatomical change happened.

What happened to the femur?

The femur developed a more pronounced inward angle (valgus angle), bringing the knees closer to the body's midline.

Why is the valgus angle useful for bipedalism?

It positions the knees beneath the body, helping maintain balance and efficient upright walking.

What happened to the spine?

It developed a more pronounced S-shaped curvature. (Australopithecus →)

Why is the S-shaped spine useful?

It helps position the upper body over the pelvis and absorb forces during upright walking.

What happened to overall limb proportions?

Legs became relatively longer and arms became relatively shorter compared with earlier ape-like ancestors.

Why are longer legs advantageous for efficient walking?

They increase stride length and can make long-distance walking more energy efficient.

Why might bipedalism have been favoured by natural selection?

It may have helped conserve energy during long-distance travel, freed the hands for carrying food/tools, and reduced exposure to overhead sunlight while increasing exposure to cooling air.

How did bipedalism free the hands?

Walking on two legs meant the forelimbs were no longer required for locomotion, allowing the hands to carry, manipulate objects and use tools.

How could bipedalism help with carrying food?

Hands were free to carry food or resources while travelling between locations.

How could bipedalism and tool use have influenced each other?

Answer: Bipedalism freed the hands for manipulation and tool use, while increasing reliance on tools could have created selection for greater manual and cognitive abilities.

What possible relationship exists between increasing brain size and tool complexity?

Answer: Larger brains may have supported greater planning, learning and problem-solving, allowing increasingly complex tools to be made and used.

How could changes in diet relate to brain evolution?

Answer: Higher-quality, easier-to-digest foods and food processing may have provided more energy, potentially supporting the high energetic demands of a larger brain.

How could social living have contributed to brain evolution?

Answer: Living in complex social groups requires communication, cooperation, learning and remembering social relationships, potentially favouring greater cognitive abilities.

Does a larger brain automatically mean a species was 'more evolved'?

Answer: No. Evolution is not a progression toward perfection. Brain size is only one measure, and different species adapted to different environments.

What are the four major stone-tool technologies to know?

Answer: Oldowan (2.6mya) → Acheulean (1.76mya) → Mousterian (160-40,000ya) → Upper Palaeolithic (50-12,000ya)

How were Oldowan tools made?

Answer: A hammerstone was struck against a stone core, removing flakes and producing sharp edges.

What could Oldowan tools be used for?

Answer: Cutting meat, processing plants, scraping and other basic tasks.

How were Acheulean handaxes made?

Answer: Stone was repeatedly struck to remove flakes from both sides, gradually shaping the tool.

What does the Acheulean handaxe suggest about cognition?

Answer: Its deliberate, symmetrical shape suggests greater planning, skill and control than simpler flake tools.

Why is Levallois technology significant?

It demonstrates planning and control in tool manufacture.

What overall trend can be seen in stone-tool technology?

Answer: Tools generally became more diverse, specialised and technologically complex, although technological change was not perfectly linear.

How can increasing tool complexity be evidence for cognitive evolution?

Answer: More complex tools can require greater planning, learning, precision and problem-solving, providing evidence of increasingly sophisticated behaviour.

Why is tool evidence not proof that brain size directly caused technological change?

Answer: Behaviour is influenced by many factors, including environment, culture, available materials and social learning, so the relationship is not simply one-way.

What are examples of prehistoric art/symbolic behaviour?

Answer: Cave paintings, engravings, pigment use, personal ornaments and carved/figurative objects.

What pigments were commonly used in prehistoric art?

Answer: Natural mineral pigments such as ochre, which can produce red, yellow and brown colours.

How could prehistoric people apply pigment to cave walls?

Answer: They could paint, rub or blow/spray pigment onto surfaces.

What are examples of prehistoric art/symbolic behaviour?

Answer: Cave paintings, engravings, pigment use, personal ornaments and carved/figurative objects.

What pigments were commonly used in prehistoric art?

Answer: Natural mineral pigments such as ochre, which can produce red, yellow and brown colours.

How could prehistoric people apply pigment to cave walls?

Answer: They could paint, rub or blow/spray pigment onto surfaces.

Why is prehistoric art important evidence for human evolution?

Answer: It provides evidence of symbolic thought, communication, creativity and complex cultural behaviour.

Can all prehistoric art confidently be attributed to Homo sapiens?

Answer: No. Some art and symbolic evidence is securely associated with H. sapiens, while the makers of some older evidence are uncertain. Neanderthals also show evidence of pigment use and possible symbolic behaviour.

Why is it dangerous to say 'Neanderthals couldn't make art'?

Answer: Evidence suggests Neanderthals had some forms of symbolic behaviour, so the old idea that symbolic behaviour belonged exclusively to H. sapiens is too simplistic.