Evolutionary Trends, hominid evolution

Question 1

Order of evolutionary ancestry

Answer 1

Hominins
Australopithecines
Homos (erectus, neanderthalensis)
Homo sapiens (modern humans)

Question 2

Define adaptation

Answer 2

Structure, physiological process or form of behaviour that makes an organism better able to survive and reproduce in a particular environment

Question 3

Adaption to skull?

Answer 3

Reduced prognathism- skull on vertebrae, reduction of teeth size, flat profile

Foramen magnum-
hominins: centrally underneath skull, skull balanced in vertebrae, limited muscles required.

Apes: Foramen magnum – Posteriorly positioned foramen magnum under the base of the skull, pushes the centre of gravity in front of the pelvis

Question 4

Adaption of the spinal column

Answer 4

-Hominins ‘s’ shaped spine - low Center of gravity. S shape curvature brings vertebral column directly under weight of skull. Improves balance in upright position. While the lumbar vertebrae is thick & wedge shaped from front to back supporting the upper body weight.

Gorilla- C shaped - high Center of gravity. C shaped curvature of the spine projects centre of gravity forward of the pelvis/ for improved balance in the quadrupedal position.

Question 5

Adaption of Jaw?

Answer 5

A- protruding jaw

H- flat allowing for skull to balance on top of spine because weight in front of foremen magnum = weight behind

Question 6

Adaption of pelvis?

Answer 6

Hominins: bowl shaped and broader supporting abdominal organs, transferring weight, helping with childbirth and pregnancy and providing muscle attachments for large gluteal muscles

Gorilla- elongated flat pelvis Allows hind limbs to move under centre of gravity which is in front of the pelvis.

Question 7

Adaption of hip and femur

Answer 7

• head of femur large and fits into acetabulum (hip socket) of the pelvis because pelvis is broad. femurs converge towards the knees ensuring:
  Weight distribution and creating the carrying angle. Remaining close to the central axis of the body when walking = stability, rotation from lower leg and foot, stride instead of swaying walk

Gorilla: Hip joint located behind head/ trunk
femur positioned vertically so no carrying angle

Hominin: pelvis shape makes hip sockets further apart and femur sit in acetabulum So joint is more forward = carrying angle

Question 8

Adaption of knee?

Answer 8

Hominin knee - bicondylar angle bringing feet in line with Center of gravity when walking
= weight transferred from femur to outer hinge so outer ligament is larger and stronger than inner ligament
no energy required to stand
Naturally resistance to knee bending backwards

Question 9

Adaption of foot?

Answer 9

Ape- opposable big toe + knuckle walking
Hominin- lost opposablity; big toe pushes off
Structured to transfer weight equally
Two arched ( longitudinal and transverse)

Question 10

Adaption of centre of gravity

Answer 10

• longer human legs= lower centre of gravity

- lower centre of gravity = increased stability when moving bipedally or standing erect

Question 11

What is muscle tone?

Answer 11

Partial contraction of skeletal muscles and is an essential element for maintaining upward stance.

Question 12

Human brain vs ape brain?

Answer 12

H- more dev. Cerebral cortex (more convulsions and SA )
- average 1350cm cubed

A- 400 to 500cm cubed

Question 13

What are endoclast?

Answer 13

Impressions inside skull made from rock or some other solid materials

Question 14

Define prehensile

Answer 14

Grasping; refers to the digits of a hand or a foot that can grasp an object. Prehensibility is the ability to grasp objects

Question 15

Origin, location and cranial capacity of Australopithecines afarensis ‘lucy’

Answer 15

Australopithecus afarensis
East Africa	
3.9 mya- 3 mya	
Cranial capacity of 375-550
O

Question 16

Origin, location and cranial capacity of Australopithecus africanus?

Answer 16

South Africa
3.0- 2 mya
Cranial capacity: 420-500

Question 17

Origin, location and cranial capacity of Paranthropus robustus?

Answer 17

East and South Africa
2.5- 1.1 mya
Cranial capacity: 500-545

Question 18

Origin, location and cranial capacity of Homo habilis?

Answer 18

Eastern Africa
2.4- 1.5 mya
Cranial capacity of 500-800

Question 19

Origin, location and cranial capacity of Homo erectus?

Answer 19

Asia and europe
1 mya- 300 000ya
Cranial capacity of 1000-1250

Question 20

Origin, location and cranial capacity of Homo neanderthalensis?

Answer 20

Europe and Asia
230000- 28000 ya
Cranial capacity of 1450

Question 21

Origin, location and cranial capacity of archaic Homo sapiens?

Answer 21

Africa Asia and Europe
300000 ya
Cranial capacity of 1100-1400

Question 22

Location, origin and cranial capacity of modern Homo sapiens?

Answer 22

Everywhere
160000 ya
Cranial capacity 1350

Question 23

Define binomial system

Answer 23

The system of naming organisms using the generic (genus) and (species) names to describe a species

Question 24

Define phylum

Answer 24

A catergory of biological classification; one of the principle divisions of a kingdom; consists of one of more classes

Question 25

What is a phylogenetic tree

Answer 25

A diagram showing evolutionary relationships between related organisms; also called a dendrogram

Question 26

Define order

Answer 26

A category in the classification of organisms; the order of classification between class and family

Question 27

What is in hominidae ( family level)

Answer 27

Hominins includes all modern and extinct chimpanzees, gorillas, orangutans and and humans

Question 28

What is in hominins ( tribe level)

Answer 28

Includes extinct ancestors of humans and modern humans

Question 29

Hominid

Answer 29

The group consisting of all modern & extinct Great Apes (that is, modern humans, chimpanzees, gorillas & orang-utans plus all their immediate ancestors).

Question 30

Define Hominins

Answer 30

The group consisting of modern humans, extinct human species & all our immediate ancestors.

Question 31

Define evolution

Answer 31

Slow gradual change in characteristics of a species. Great Apes Humans Relative size of cerebral cortex

Question 32

Relative size of cerebral cortex | Apes v Humans

Answer 32

``` Apes Smaller cranial capacity Sagittarius crest foremen magnum towards back Prominent brow ridges Less rounded cranium ``` ``` Humans Larger cranial Capacity No Sagittarius crest Vertical forehead foramen magnum moved centrally below Reduced brow ridges Rounded cranium ```

Question 33

Mobility of digits | apes v humans

Answer 33

``` Apes Less opposable first digit Opposable big toe Precision grip Power grip Shorter thumb relative to other digits ``` ``` Humans More opposable first digit Non-opposable big toe Precision grip Power grip Longer thumb relative to other digits ```

Question 34

Locomotion | apes v humans

Answer 34

Apes Quadrupedal Humans Bipedal

Question 35

Prognathism | Apes v humans

Answer 35

``` Apes prognathic face Large jaw No chin Larger molars & canines 5. Diastema U shape dental arcade ``` ``` Humans Flatter face Small jaw Definite chin Smaller molars & canines No diastema Parabolic dental arcade " ```

Question 36

Adaptions to ribcage

Answer 36

reduced size/ weight Gorilla: Apes have a rounder, barrel shaped rib cage, pushes the centre of gravity in front of the pelvis. It is also large to support abdominal organs. Hominins: pelvis supports abdominal organs

Question 37

What is the carrying angle

Answer 37

Carrying angle- convergence of femur at the knee So weight is distributed to the center of the body = increased stability when moving = striding gait = body rotates towards midline as walk pulling leg into a straight line.

Question 38

Define primate

Answer 38

A member of an order of mammals that includes lemurs, lorises, tarsiers, monkeys, apes and humans

Question 39

Define culture

Answer 39

Culture – The range of learned behaviour patterns acquired by a species/population

Question 40

Tool trends

Answer 40

Trends – Increase in the variety of tools made. Increase in the complexity of manufacturing process of the tool. Increase in the quality of workmanship. Increase in the range of materials used to produce tools. Increase in the number of different activities tools are used for

Question 41

Tool culture used by Australopithecines/ Paranthropus?

Answer 41

Oldowan/ 2.6- 1.7 mya "Pebble tools, chippers, scrapers , flakes and chisels. Stone/ Percussion flaking

Question 42

Tool culture used by Homo habilis

Answer 42

Oldowan/ 2.4- 1.5mya "Pebble tools, chippers, scrapers , flakes and chisels. Stone/ Percussion flaking"

Question 43

Tool culture used by Homo erectus

Answer 43

Acheulean/ 1.7 mya– 100000 “Stone +Percussion flaking Flaked around all edges Hand axes/ teardrop shapes"

Question 44

Tool culture used by Homo neanderthalensis

Answer 44

Mousterian/ 200000 – 400000 "Stone, wood, bone-> ‘hafting’ Specific tools- piercing, gouging, scrapes Flint stone"

Question 45

Tool culture used by early cromagnon Homo sapiens

Answer 45

43000 – 26000 aurignacian Stone, wood & bone/ punch flaking

Question 46

Tool culture used by later cro magnon Homo sapiens

Answer 46

22000 – 19000 Solutrean Characterised by pressure flaking stones to produce artful willow leaf and laurel leaf points. Used Stone, wood & bone/pressure flaking

Question 47

Tool culture used by latest cromagnon Homo sapiens

Answer 47

18000 – 12000 Magdalenian Dominance of bone and antler tools over flint and Stone. Used wood & bone/Hafting, punching & pressure flaking

Question 48

Australopithecines/ Paranthropus lifestyle, food, hunter gatherers?

Answer 48

Lifestyle: slept in trees at night, during day- terrestrial, had home bases Food- herbivores- hard, brittle. Ate seeds/ nuts. Ate grasses/ fruits/ tubers Hunting/gatherers- gatherers

Question 49

Homo habilis lifestyle, food, hunter gatherers?

Answer 49

Homo Habilis Lifestyle: interdependent, lived together in small groups Food- omnivores: mainly plants, eating meant occasionally. Protein + lipids = brain development Hunting/ gathering: both hunters/ scavengers for meat. Some bones show cuts made by stone tools and teeth showing how they ate meat -> food sharing

Question 50

Homo erectus lifestyle, food, hunter gatherers?

Answer 50

Homo erectus Lifestyle: independent from environment-> used it to their advantage: built shelters and used fire Food: omnivores/ meat- fish and deers. Veg- nuts and fruits (70%). Fire- cooked-> safe to eat. Hunter/ gathering: skilful hunters, employing many capturing techniques eg, using fire to herd elephants and gathering tools from 33km away to capture prey.

Question 51

Homo neanderthalensis lifestyle, food, hunter gatherers?

Answer 51

Homo neanderthanlensis Lifestyle: caves, harsh conditions-> able to adapt and respond to environment. Clothes-> animal hides Food- omnivores- 80% meat p- mammoths, rhinos, deers and horses. Preserved and STORED meat. Hunting/ gathering; strong built and able to run long distances to catch prey, they even herded prey into areas where they could ambush them. - organised hunting.

Question 52

Homo sapiens lifestyle, food, hunter gatherers?, social systems, communications beliefs and tools.

Answer 52

Homo sapiens Lifestyle: scattered -> small populations, nomadic-> villages, better shelters Food: meat based (archaic). Domesticated plants/ animals ( farming + agriculture) ~ 12000 years ago Hunting/ gathering: able to catch prey using tracking methods and cages to trap them temporarily. Hunted bisons, venisons, reindeers, rabbits. Plants, seeds, Nuts. Also herded animals

Question 53

Australopithecines/ Paranthropus social systems, communications, beliefs and tools?

Answer 53

Social systems- males stayed close to home and collected food. Females dispersed after puberty and cared for the young. They were no neighbouring groups Communication- no speech, vocal cords are similar to chimps making only rudimentary sounds Beliefs- N/A Tools- oldowan

Question 54

Homo habillus social systems, communications, beliefs and tools?

Answer 54

Social system: liked to share things and look after each other, increased interdependence and group close knit and able to function as a social and economic unit. Men hunted, women and females gathered. Communication: hands (visual signals), voice (simple)- pressure for communication increase, speech producing area bigger Beliefs- N/A Tools: oldowan

Question 55

Homo erecus social systems, communications, beliefs and tools?

Answer 55

Social system: women- gatherers due to demand for child caring. Care of young was becoming increasingly important. Also a greater emphasis on mutual cooperation and complex society developed. Communication: gene for speech + language may have developed. Pressure for speech increased and spoken language may have arisen Beliefs: NA Tools: Archeulian tool culture

Question 56

Homo neanderthalenisis social systems, communications, beliefs and tools?

Answer 56

Social systems: cared for disabled, shared resources developed social systems for sharing food and other resources, traded with Homo sapiens and older children learned from adults Communication: relatively advanced language skills. Larynx similar to H. Sapiens Belief: strong indication they buried their dead suggesting they believed in life after death. Ceremonial burial seems to be practiced. Art and music development. Tools: Moustierian tool culture

Question 57

Homo sapiens social systems, communications, beliefs and tools?

Answer 57

Social system- innovations in clothing, complex social system, very few members involved in food production and most occupied in other pursuits, Communication: symbolic language-> written Beliefs- artistic, innovative. Religion. Art, music. Jewellery, body modifications, rituals and ceremonies. Tools: aurignacian, solutrean, magdalenian, upper Palaeolithic tools

Question 58

Bipedal vs quadrupedal adaptions

Answer 58

``` Apes Quadrupedal C shaped spinal curve Less wedge shaped lumbar vertebrae Thinner lower vertebrae Longer, narrow pelvis Lesser carrying angle Longer arms than legs Longitudinal arch only ``` Humans Bipedal S shaped spinal curve More wedge shaped lumbar vertebrae Thicker lower vertebrae Shorter, wider pelvis Greater carrying angle Shorter arms than legs Longitudinal/transverse Larger heel bone"