Human Evolution Flashcards
Homonins
Taxonomic group that includes modern humans and ancestral humans (Homo spp, Australopithecus spp, Ardiphethecus spp)
Primates are distinguished by (5 things)
- Comparatively LARGE BRAIN relative to body size
- Well-developed BINOCULAR VIDSION with forward facing, enclosed eye sockets in the skull
- COLOUR VISIOIN
- Grasping hands that have MOBILE FINGERS AND TOES with flat nails (not claws), and sensitive finger pads
- A REDUCED SENSE OF SMELL and a small snout
Foramen magnum
The hole on the underside of the skull through shich the spinal cord passes.
In all bipedal species, the foramen magnum is centrallly located so that skull balances on top of spine.
Nuchal crest
Where muscles are attached to the skull
Small in bipedals and large in quadrupeds because we don’t have large neck muscles since we don’t need to hold our skull up
On the Chimp skull, there are 8 things to be labelled that are similar/different to human skull. On the human skull, there are 6 things to label. DO it.
Why human spine S shaped and apes is C shaped?
S in humans to act as a shock absorber and keep body wieght above hip joints for upright stance and movement
C in apes because the slight curvature counterbalances the downward force of organs and chest in the more horizontal stance
Valgus angle
The angle between the shaft of femur and the vertical when femur is in normal standing orientation
Just fyi, what does opposable mean?
(of the thumb of a primate) capable of facing and touching the other digits on the same hand.
Just fyi, what is brachiating?
(of certain apes) move by using the arms to swing from branch to branch.
Diastema
The gap in the between the upper canine and premolar found in great apes (no one had them - Australopithecines, Homos or modern humans. Chimps do though).
Homo erectus
The first human to use fire and spread out from Africa
Used Acheulian tools
Oldowan tools
Oldowan tools were made by H. habilis (2 mya).
The simple partly shaped (~6 blows) stones and flakes would have allowed them to access food that other species could not, such as scavenging bone marrow. (This may also have provided the protein required for further brain development.)
Valgus angle
The angle between the shaft of femur and the vertical when femur is in normal standing orientation
Angles knees closer to centre of gravity so we dont swagger when we walk and this conserves energy
Hominin
The group consisting of modern humans, extinct human species and all our immediate ancestors (including members of the genera Homo, Australopithecus, Paranthropus and Ardipithecus). All bipedal.
Acheulian tools
Acheulean tools were fully shaped (~50 blows) and more refined.
H. ergaster / H. erectus (~1 mya) would use the hand axes to dig roots, hack tree branches, and (for flakes) scrape and cut animal hides. This would have benefitted their users by providing more food and perhaps defence from predators.
Homo habilis
The first Hominin to use tools.
Successful hunters, first to have speech (grunts), simple shelters, more sophisticated brain than Australopithecus afarensis.
Hominoidea
The word to describe the great apes, humans and their ancestors
Wernicke’s area
The brain centre responsible for interpreting speech
Cultural evolution
The type of evolution where things are taught/ learned and not passed on in the DNA
Homo heidelbergensis
The group of hominin that were initially called archaic Homo sapiens and was the first with firm evidence for systematic hunting. Used Acheulian tools.
Occipital condyle
The part of the brain that articulates with the first vertebra
Biological evolution
The type of evolution that is passed on through our DNA
Mousterian tools
Mousterian tools (~500 kya) were more refined again (~150 blows), and more diverse in their form and functions. The blades were sharper, requiring more blows to produce. Each tool was more specialised. Rope may have been used to create spears for hunting, and awls (pin to male holes) were made for punching holes in hide which, with hide lacings, could be used to make clothing, benefitting the Neanderthals to survive in their cold environment in ice-age Europe.
Homo neanderthalensis
The group of Hominin that first buried the dead and cared for the old
Cerebrum
The newest (evolutionarily) and largest part of the brain as a whole. It is here that things like perception, imagination, thought, judgment, and decision occur
What shape is the pelvis and why?
Bowl shaped
- Reduces stress of weight of upper body on hips
- Supports internal organs
- Strong pelvis bone to support large muscles for walking
- Allows for birth of babies with alrge heads
Link sagittal crest, zygomatic arch and brow ridges together
The sagittal crest is where the large jaw muslces needed to move the large heavy mandible are attached to the skull.
These large jaw muslces then pass through the zygomatic arch.
The brow ridge above eyes support the skull against the stresses that result rom the chewing.
Australopithecus afarensis
The scientific name for “Lucy” the first to probable walk upright
Lower Palaeolithic
The name for the culture that included the Oldowan and Acheulian together. Also called ‘Old Stone Age’
Upper Palaeolithic
Upper Palaeolithic tools (from ~50 kya) were more finely worked again (~250 blows), and most significantly they used a variety of materials, including bone, ivory and antler. This enabled a diverse range of tools, including very finely worked and delicate items, to be made. This included fish hooks and harpoons, increasing H. sapien’s diet, and needles, improving their clothing and even enabling the manufacture of shelters. This could have allowed their range to increase and allowed for a rapid expansion and colonisation of new areas.
Composite
A tool made of more than one kind of material
Multiregional
The multiregional theory (MRT) states that hominins around the world formed a single species which, through interbreeding, evolved together into modern humans with regional (racial) differences.
Homo sapiens
The first species to make and use needles
Out of Africa
Out of Africa (OOA) states that H. sapiens evolved in Africa and dispersed from there around 140 kya. As they spread into Europe, Asia, and beyond they outcompeted other such species from previous migrations and were eventually the only remaining hominin species
Protruding jaw
Prognathism (it redcued over time)
How did Australopithecus obtain food?
Scavenging what they found
What does cooking food do to it?
Softens it, kill microbes
What where the advantages of fire?
Cooks food, hardens tools, lengthens day, kept warm, keeps predators away
How did tools help Hominin survive?
Allowed more diverse animals to be killed and processed
What is the name for the differences observed between male and female skeletons?
Sexual dimorphism
How did the feet change when we became bipedal?
Forward facing big toe, arched, big toe attached
Why is the Out of Africa hypothesis also called replacement hypothesis?
When they moved out of Africa, they out competed any Hominin they came into contact with, making them extinct
What are the advantages of being bipedal?
Taller so can see predators / food, hands free to carry food/ young / tools, more efficient cooling
How has cultural evolution changed over time?
Tools better, use of shelter, abstract thought, imagination, domestication of animals / plants
What do Lower Palaeolithic – Oldowan tools look like?
Pebbles with flakes knocked off one edge
What do Lower Palaeolithic – Acheulian tools look like?
Tear drop shaped pebbles
What are the Middle Palaeolithic tools?
Mousterian and scrapers axe heads
What are the Upper Palaeolithic tools?
Needles, fish hocks made from bone and wood
What does the evidence of Cave drawings, burial of dead, planned hunting groups indicate?
The ability for abstract thought
What shape/ dental arcade is the jaw in apes?
“U” or rectangle
What shape/ dental arcade is the jaw in humans?
Parabola
What are the advantages of a shorter pelvis?
It is stronger & able to tilt and rotate during walking
