Chapter 17 - 20 Test Flashcards
What are primates?
Humans, apes and monkeys are called primates because they are classified in the order of primates
Why are non-human primates of interest?
Non-human primates are of interest as they are the closest living relatives of our own species
What can be used to develop an understanding of how human characteristics evolved?
Comparative anatomy of primates
Comparative biochemistry
Behaviour of living primates
Fossil of primates
What is a hierarchy in terms of species categorisation?
A hierarchy is a series of groups that move from broad, general categories o narrow specific ones
What kingdom do primates belong to?
The animal kingdom
What are the categories of a hierarchy?
Kingdom - phyla - classes - orders
What occurs as you move down the hierarchy?
Organisms in each group have more and more characteristics in common
What are differences between the primates known as?
Evolutionary Trends
What is the name given for humans in the hierarchy?
The genus is referred to as ‘homo’ - includes both modern and extinct humans. The species category is known as ‘sapiens’ - only modern humans
What do only humans being apart of the species section indicate?
As humans are the only primate in the species section, humans have evolved far greater than any other primates
What is an arboreal environment?
Tree like environment
What are some features of for classifying primates?
- Grasping fingers and toes
- Overlapping vision
- Pentadactyl (5 fingers/toes)
- Nails instead of claws
- Larger and more complex brain
What are the five trends that gradually change over time?
Dentition Digits Vision Cerebral Cortex Gestation and Parental Care
Why is being pentadactyl useful for primates?
Being pentadactyl is used for primates to be mobile, living an arboreal life (living in trees) where grasping/prehensile digits are essential for climbing/wrapping digits around trees
Define prehensile
grasping; refers to the digits of the hand or foot that can grasp an object
What is opposability?
When the first digit (thumb or big toe) can be moved to touch other digits
What causes the ability of opposability to vary in primates?
The ability to do this in primates will vary and depend on how long their first digit is
What enables primates to secure grip on tree branches?
They have nails instead of claws on their fingers and toes, and friction ridges which will allow them to grasp on the branch better
What is precision grip?
The thumb and fingers are used to manipulate an object - used to hold objects such as a pencil for writing, sewing and painting (fine motor skills)
What is one evolutionary trend of the teeth that has occurred in primates?
One evolutionary trend in primate dentition that has emerged is a gradual reduction in the number of teeth compared with earlier mammals
What is a dental formula?
This gives the total number of teeth for each incisor, canine, premolars and molars of 1/4 of the jaw
What is the human dental formula?
2.1.2.3
Which primates is the dental comb found in?
More primitive primates such as the lemur and loris
What is the dental comb used for?
Grooming of fur - does not provide a dietary function
What is the diastema?
The diastema is a tooth gap found in old world monkeys and apes. It is located between the upper second incisor and the upper canine - made so the jaw can close more comfortably
Who had three cusped molars?
Early mammals and primitive primates
Who has four cusped molars?
Old world monkeys
Who has five cusped molars?
Humans and apes
What would an increased number of cusps in the molars indicate?
The increased number of cusps would be for a specialised diet of more plant material
What has primate brain size done?
Increased
Where has the greatest increase in size been in the primate brains?
Cerebral hemispheres
Which primates have a higher convoluted or more folded cerebral cortex?
Humans and apes (higher primates)
What has an increased size in the cerebral cortex allowed?
The increase in the size of the cerebral cortex has allowed primates to move about, locate food, and develop special skills (tool making)
What are the differences between other primate brains and human brains?
Primates = larger section for smell and sight Humans = large section for site, smaller smell section
What is the name of the Homo Habilis tools?
Oldowan tools
What were the Homo Habilis tools?
Pebbles with flakes removed
Simple blades and hammers
What were the uses of Homo Habilis tools?
Evidence shows an increase in a slightly larger brain which suggests they ate meat, so their tools were most likely used for cutting meat
What were the Homo Erectus tools called?
Acheulian Tools
What were the Homo Erectus tools?
Made from stone and bone, and flaked all around the edges to form a tear drop shape
What were the uses of Homo Erectus tools?
Used as hand axes
Possible use for digging up plants or roots, and cutting meat
Used for skinning animals
Shows use of fire
What was the name of Homo Neanderthalensis Tools?
Mousterian Tools
What were the Homo Neanderthalensis tools?
More refined and more specialized. Made stone flakes that could be used for cutting scrapping, piercing and gouging
What did the Homo Neanderthalensis use their tools for?
Became use of cutting meat and making clothing
What were the three types of tools of the early Homo Sapiens?
Aurignacian Tools
Solutrean Tools
Magdalenian Tools
What were the early Homo Sapien tools?
Use of finer blades and projectile weapons
Use of bone and ivory to make tools to attach to wooden shafts
Used pressure flaking to rework or sharpen tools
What did the early Homo Sapiens use their tools for?
Increase in a variety of uses such as fishing, preparing skins for clothing (needles), and building of shelters
What’s the difference between the neanderthalensis and the sapiens foreheads?
N: Sloping
S: High, vertical
Whats the difference between the neanderthalensis and sapiens brow ridges?
N: Double arched brow ridge
S: Small or no brow ridge
Whats the difference between the neanderthalensis and sapiens prognathism?
N: Weak chin, powerful jaw
S: Sizeable jaw, projecting chin
Whats the difference between the neanderthalensis and sapiens dentition?
N: Teeth are smaller than the Homo Erectus but bigger than modern humans
S: Reduced tooth size with thinner enamel, shorter and smaller than neanderthalensis teeth
Whats the difference between the neanderthalensis and sapiens cranial capacity?
N: Approximately 1600 cm3 on average
S: Approximately 1350 cm3 on average
What is the difference between the cheek bones of Neandertals and sapiens?
N: Swept back, lightly built
S: Similar to neanderthals
What is the difference between the back of the skull in Neandertals and sapiens?
N: Drawn out in a bun shape
S: Rounded
Define tribe
A level of biological classification that occurs between subfamily and genus
What tribe do humans belong to?
Hominini
Define bipedal locomotion
Walking up-right on two legs
What is the difference between the posture of Gorilla and Human skeletons?
G: C-shaped, quadra-pedal
H: S-shaped, bipedal
What is the difference between the position of the foramen magnum in Gorillas and Humans?
G: Foramen magnum towards back of the skull
H: More downward facing foramen magnum - under the centre of the skull
What is the difference between the curvature of the spinal column in Gorillas and Humans?
G: Back (lumbar) vertebrae less wedge shaped - has larger cervical vertebrae to hold its neck or keep it up
H: Lumbar vertebrae more wedge shaped - have thicker lumbar due to the vertebral column sitting directly under the skull
What is the difference between the jaw in the gorilla and humans?
G: More protruding jaw, thicker mandible
H: Flatter face, thinner mandible
What is the difference between the pelvis in gorillas and humans?
G: Narrow and longer from top to bottom, flatter shape
H: Broader and shorter from top to bottom, bowl shaped to support abdominal organs when standing erect and for females to carry offspring
What does a bowl shaped pelvis provide for humans?
Provides space for large buttock muscles which move the legs and keep the body erect
What is the difference between the carrying angle of gorillas and humans?
G: doesn’t have a correct striding gait as they tend to sway side to side. The hip joint is positioned straight over the knee which causes sway
H: femurs positioned wide apart, large femoral head due to centre of gravity and shape of pelvis, allows for striding gait where we walk heel to toe
What is the difference between the knee of the gorilla and humans?
G: Knee cannot be straightened
H: Outer ‘hinge’ larger and stronger to take weight of body, knee is able to be straightened
What is the difference between the foot of gorillas and humans?
G: Heel is smaller in size and foot only has one longitudinal arch - no transverse arch
H: Increased size of heel bnne and alignment of the big toe. Foot has both 2 longitudinal arches and 1 transverse arch
What is the difference between the centre of gravity in gorillas and humans?
G: arms are longer than legs, shorter striding gait, due to arms being longer COG is higher up in the body
H: Arms are shorter than legs, due to longer legs humans are able to increase the length of the stride when walking, low centre of gravity due to shorter arms
What is the is the difference between the dental arcade of apes and humans?
Apes: U-shaped
Humans: Parabolic
What is the difference between the brain size in apes and humans?
Apes: 400 cm3
Humans: 1350 cm3
What is the difference between ape jaws and human jaws?
Apes and early hominins had a very forward jutting jaw which was accompanied with prominent brow ridges, Humans have a reduction in the brow ride and a flatter face with a chin
