becoming human-ch11

Question 1

What are the taxonmic classifications of humans

Answer 1

Humans belong to the kingdom Animalia
Humans belong to the Phylum, Chordata
Humans belong to the class, Mammals
Humans belong to the order, primate
Superfamily-hominoidea
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5. Humans belong to the family, Hominidae

Humans belong to the tribe Hominini

Humans belong to the genus–homo
7.Humans belong to the species- sapiens

Hence the scineitifc name for humans is homosapeins.

Question 2

Characteristics of primates

Answer 2

rimates have a prehensal abilty, meaning they have the abilty to grip objects–they can do this because of their opposable digit(big thumb or toe) which allows them to grasp objects with precision and power grip

Primates have a flexible spinewhich increases flexibilty, allowing primates to live in trees.

Primates have a large cranium

Primates have 3D colour vision, broad rib cage, superior intelleigene and problem sovling skills

Question 2

Characteristics of mammals

Answer 2

Mammals are warm blooded verterbrates,

Mammals have fur/hair

Mammals have mammary glands to produce milk

Mammals have one lower jawbone directyl attached to the skull, giving mammals a powerful bite

, three middle earbones and variety of teeth include incisors. molars, premolars an d canines. Canines tear food apart whilst molars grind down food, incisors bite/pierce food

Question 3

Characteristics of Hominoids

Answer 3

Hominoids have a shorter spine, no tail, longer arms than legs(except humans)

Question 4

Characteristics of hominins

Answer 4

Hominins have the characteris of bipedalism which is unique to hominins such as homo sapiens and homo erectus.

Question 5

Compare the humans which are hominis to gorillas

Answer 5

Humans have an S shaped spine, whereas gorillas have a C shaped spine.

Humans have shorter hands, straighter fingers and longer thumbs whereas gorillas have more curved fingers that are adapted for climbing trees and knuckle walking.

Gorillas have a funnel shaped ribcage, whereas Humans have a barrel shaped ribcage.

Question 6

What are hominoids

Answer 6

Hominoids(super family) are a group of primates that includes all apes except monkeys that are characterised by larger brains, no tails, and more complex behaviours.

Question 7

What are hominins

Answer 7

hominins are a group of primates where humans seperatefrom ther hominoidsthat includes modern humans and their closest extinct relatives, characterized by traits such as bipedalism and larger brain sizes

Question 8

Compare hominoids and hominins

Answer 8

Hominoids are comprised of all apes but not monkeys. Homoinds charactierisics include no tail, broad chest, large brain, semi erect or fully erect posture. examplesinclude gorillas, chimpanzees

Hominins:
Where are where humans seperate from other hominoids, include modern humans, extinct homo ancestors, and the charactierisc sinclude bipedal iwht modified pelvis, feet central foramen magnum.
examples include humans or homo neanderthalensis.

Question 9

What happened in evolution when the cranium capacity increased in size

Answer 9

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

Question 10

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

eg. whyare humans smarter than gorillas

Answer 10

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 11

Why can humans talk but not other homo specieslike gorillas

Answer 11

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 12

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

Answer 12

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

Question 13

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

Answer 13

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 14

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

Answer 14

a more centralised foramen magnum
A less protuding chin
Smaller teeth
lessening of the brow ridge
flattening of the face

Question 15

Bipedalism

Answer 15

the abilty to walk on 2 legs and upright posture.

Question 16

How did bipedalism change the spine of hominins/humans

Answer 16

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 17

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.

Answer 17

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 18

How did bipedalism cause changes to legs in hominins

Answer 18

legs are stronger than arms

stronger knee joint

Knee position inwards(carrying angle) to help with the weight of the body when walking

Question 19

What changes to feet and hands did bipedalism cause for hominins

Answer 19

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 20

What are the advantages of bipedalism

Answer 20

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

Question 21

In hominins evoltuion how did limb structure chnage

Answer 21

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 22

Australopithecus
australopithecus

Answer 22

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

Question 23

Evidence for examining homosapiesn past

Answer 23

fossil records to determine relatdness with other species like Naedethnrals
2.Molecular homology( DNA sequences or amino acid sequences)

3.New fossils are still bein discoverd

4.Many fossils have differnet interpretations of human fossil records

Question 24

Various theories on the evolution of humans:

Answer 24

ultiregional hypothesis
Out of Africa Hypothesis

Question 25

Out of Africa Hypothesis

Answer 25

suggests that Homo sapiens evolved in Africa around 200,000 to 300,000 years ago then emigrated 100,000 years later to Europe, Asia and austriala, replacing existing hominin species such as Homo erectus.
Most widely accepted hypothesis

Question 26

Evidence of out of aFRICA hypothesis

Answer 26

Evidence:
-mtDNA analysis of modern humans trace back mitochondria lineages from a common ancestor in Africa
-Modern humans show little genetic diversity compared to other species suggesting we originated from a small centralised population
-Oldest Homo sapiens fossil found in East Africa dated 160,000 years compared to fossil in middle East 100,000 years old.
-Evidence of tools, cave paintings found in regions of Western Europe around 40,000 years old.

Question 27

Multiregional hypothesis

Answer 27

Suggests evolution of modern humans from Homo erectus to Homo Sapiens was an ongoing process across all regions of the world with gene flow between different continental populations.

Homo erectus moved out of Africa to other parts of the world

Homo erectus evolved into Homo Sapiens in different regions

Limited evidence.
Not accepted.

Question 28

When was the arrival of aboriignal australians

Answer 28

Arrival of Aboriginal Australians between 50,000 and 65,000 years ago.

Question 29

Q: What does genomic research suggest about modern Aboriginal Australians’ ancestry?

Answer 29

: It suggests that they can be traced back to the ‘out of Africa’ model when the first humans spread throughout the world.

Question 30

What is Sahul?

Answer 30

Sahul was a supercontinent that included present-day Australia, New Guinea, and Tasmania, which became geographically isolated due to rising sea levels.

Question 31

What evidence exists of the impact of Aboriginal Australians’ migration

Answer 31

Evidence suggests the extinction of large Australian terrestrial animals 42,000 years ago due to the rapid migration of Aboriginal Australians.

Question 32

Migration of aboringal asustrialains

Answer 32

The first migrants reached Sahul, a supercontinent that included Australia, New Guinea, and Tasmania. Rising sea levels later separated this landmass, leading to geographic isolation. This isolation impacted the region’s flora and fauna, contributing to the extinction of large Australian animals around 42,000 years ago

Question 33

‘Country’:

Answer 33

refers to relationship between individuals and ancestral lands and seas

Question 34

Proof that humans breed with Neanderthals

Answer 34

Evidence suggests crossbreeding between the two species

Neanderthals were our close evolutionary cousin

Both existed in Europe and Asia between 40,000 and 100,000 years ago

mtDNA from Neanderthal fossils suggest we were a separate species that shared a recent common ancestor around 400,000 years ago

Question 35

Comparing Neanderthals and Humans

Answer 35

Neanderthals had:
Wider nose
Shorter limbs
Stockier build
Enlarged brow ridge
Larger cranial capacity
Better resistant to cold climates

Question 36

Evidence to suggesting interbreeding between humans and Neanderthals

Answer 36

Evidence: Nuclear DNA studies show 1-4% of human genome is identical to Neanderthals. Only found in non-African populations and not in sub-Saharan African genomes. This suggests Neanderthals may have interbreed with humans as they left Africa and did not interbreed with African humans

Evidence: 100,000-year-old Neanderthal fossil in Siberia contained human DNA. This suggests that a population of Neanderthals in Siberia interbred with humans 100,000 years ago.

Question 37

What are the new hominin species

Answer 37

Homo Denisova

Homo luzonensis

Question 38

Australopithecus

Answer 38

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

Question 39

Australopithecus characteristics

Answer 39

a
smaller skull size
2.wider rib cage
longer arms, shorter legs, suggesting able to climb on trees

2

Question 40

Why is the human fossil record so hard to interpret?

Answer 40

Not all individuals die in conditions to allow fossilisation

Rock layers and the fossils they contain may erode and disappear over time

Many rock layers are inaccessible to palaeontologists, so not all fossils have been found

Question 41

History of life key events