11B hominin evolution

Question 1

What happened in evolution when the cranium capacity increased in size

Answer 1

when the cranium capacity increased in size, there was an increase in brain mass

Question 2

Explain the relationship between cranium capacity and brain mass in early Homo species compared to modern humans.

Answer 2

The cranium capacity increased in size whcih also reflected an increase in the brain mass for modern humasn. Hence the early homo brainswere smaller than modern humans like homo erectus

Question 3

Why do hominins or humans have an increased cogntiie abilty compared to earlier homo species

eg. whyare humans smarter than gorillas

Answer 3

Cerebrum became more folded, which increased surface area of the brain, resulting in more neurons and increased connection between brain cells. With this increased intellcutual bailty came the ability of speech, the feeling of complex emotions, higher order decision making, planning.

Leading to enhanced cognitive ability

Question 4

Why can humans talk but not other homo specieslike gorillas

Answer 4

Cerebrum became more folded, which increased surface area of the brain, resulting in more neurons and increased connection between brain cells. With this increased intellcutual bailty came the ability of speech, the feeling of complex emotions, higher order decision making, planning.

Question 5

What does the fossil record of skulls suggest about brain size in hominins

Answer 5

The fossil record suggests that brain size in hominins increased over time.

Question 6

: How did the increase in brain size affect cognitive processes in hominins?

Answer 6

e increase in brain size led to enhanced cognitive processes such as planning, speech, and abstract thinking.

Question 7

What change in the cerebrum is associated with increased cognitive abilities?

Answer 7

An increase in the number of folds in the cerebrum resulted in a larger surface area, which enhanced cognitive abilities due to more neurons and increased brain cells.

Question 8

What are some higher cognitive functions that improved with the increase in brain size?

Answer 8

he increase in brain size improved functions such as speech, emotions, higher-order thinking, and decision-making.

Question 9

What were the changes to the skull of hominins due to evolution

Answer 9

1. a more centralised foramen magnum
2. A less protuding chin
3. Smaller teeth
4. lessening of the brow ridge
5. flattening of the face

Question 10

Bipedalism

Answer 10

the abilty to walk on 2 legs and upright posture.

Question 11

How did bipedalism change the spine of hominins/humans

Answer 11

hominins such as humans due to bipedalism have a S shaped surve to accomdate the upright walking posture and support weight, compared to the C shaped curve in gorillas.

Question 12

How did bipedalism causes changes to the pelvis to support the upright stance

Answer 12

Bipedalism results to changes in the pelvis to become more narrow,and made the position of the foramen magnum more central to support the upright stance

Question 13

What changes did bipedalism cause to hominins such as humans to support their abilty to walk upright on 2 legs

Answer 13

1. bipedalism changed to the pelvis to become more naroow and the foramen magnum to become more central
2. Bipedalism changed the spine to become an S shape to accomdate the upright walking posture, hence why huamns have an S shaped

3.changes to legs

4. changes to feet
5. changes to hand

Question 14

How did bipedalism cause changes to legs in hominins

Answer 14

1. legs are stronger than arms
2. stronger knee joint
3. Knee position inwards(carrying angle) to help with the weight of the body when walking

Question 15

What changes to feet and hands did bipedalism cause for hominins

Answer 15

Bipedalism caused arched feet so that feet could move in a spring like motion

Toes are shorter

Bipedalism caused refine precision grip of hands.

Question 16

What are the advantages of bipedalism

Answer 16

Advantages of bipedalism:
Hands are free to carry young, hunt
Assists in thermoregulation
Ability to see higher grounds

Question 17

In hominins evoltuion how did limb structure chnage

Answer 17

Australopithecines have longer arms for movement on trees but overtime, arms shortened for homo genus because the arms were no longer used to climb on trees, instead to carry young, hunting, and preparing food.

Hominins developed longer legs to assist in walking upright because they were bipedal, this is also enery effienct becuause longer legs allowslonger strides saving energy

Question 18

Changes to pelvis in hominis

Answer 18

1.Pelvis became shorter and more bowl shape which Provided support for the upper body for bipedalism

2.Legs attach at an angle to allow to walk upright

3.Circular birth canal for childbirth with larger cranial capacity

Question 19

Australopithecus
australopithecus

Answer 19

ancient hominin ancestor from which Homo evolved 4 million years ago
Evidence shows that they walked upright, yet still climbed on trees