12.2

More complex brain than other primates No tail Appendix Diurnal Freely rotating arms Five cusps

Relative size of the cerebral cortex Mobility of the digits Locomotion Proganisthism and dentition

Move about, locate food and social skills Enabled tool making Mutual cleaning and grooming, fighting for dominance Larger brain

Increase in size- especially cortex Large brains relative to body size Strong convultion patterns

Unspecialised limbs Pentadactyl= five digits Highly mobile Precision grip and power grip grasping toe lost, to become weight bearing

Change from quadrupedalism to bipedalism

Gradually moved forward, to become more central- allows skull to balance (hence why apes had large neck muscles)

Apes have protruding jaw, humans are flatter -Due to smaller and less teeth over time.

Pelvis in humans is shorter, broader and more bowl shaped than apes Bowl shape supports stability, and foetus development

Position of pelvis results in hip joint being directly under trunk, allows weight to be transferred Femurs also converge inwards, allows weight to be distributed evenly when walking

Outer hinge is larger and stronger COG in front of knees -Results in a force trying to bend knee backwards- resisted by ligaments= NATURAL RESISTANCE THAT REQUIRES NO ENERGY

Lost grasping ability to become a highly specialised moving organ- weight bearing Metartarsals form 2 arches: -Longitudinal (front to back) -Tranverse arch (side to side)

Longer legs= lowering centre of gravity Humans is at pelvis, apes at chest level Lower cog support bipedal movement

Partial contraction of skeletal muscles -Spine, hip, knee, ankle and abdominals -Muscles in back of neck partially cntract to avoid head slumping

Walking upright when the hip and knee are fully straightened is referred to as the striding gait

• More efficient • Leaves the hands free to use tools • Hands free to carry items • Upright stance ahieves greater height= see further • Less body to sunlight • Increas exposure to breeze= cooling mechanisms

Primitive= 3:1:4:3, three incisors, one canine, four premolars and three molars on each side= 44 teeth total

Dental arcade changed from U shaped to more parabolic

Apes and easrly hominids= Prognathism and distinct brow ridge -Tooth size decreased- flatter face, devlopment of chin and nose