Early Homo Lecture 11 Flashcards
(31 cards)
What are the two names of KNM WT 17000 and which one is most used?
The correct name is Paranthropus aethiopicus
But everyone calls it Australopithecus bosei
Why is size an important factor?
If you’re very small then gravity doesn’t effect you much but if you’re big then it does.
Which tooth gives a good estimate of body size?
The area of the M1 (occlusal length x occlusal width), but you must remember some species are megadont and others are microdont.
Which part of the body is best for estimating body size?
The width of the head of the femur is closely related to body size. Failing this, the mid shaft of the femur would also be useful.
The early hominins were relatively _________ and moderately _________ ________.
The early hominins are relatively small-bodied and moderately sexually dimorphic.
The bigger the males are compared to the females then…
Larger harem
Large animals have a relatively ______ brain than smaller animals. This is called _______ ________.
So larger animals have relatively smaller brains than smaller animals. This is called negatively allometry.
What is the encephalisation quotient?
size of brain/size of body
What is the EQ of Pan?
2.0 (double the brain size expected for the body size).
What is the EQ of Homo sapiens?
5.8
What is the EQ of Praeanthropus afarensis and Australopithecus africanus?
P. afarensis = 2.5
A. africanus = 2.7
What is the EQ of Paranthropus boisei and Paranthropus robustus?
P. boisei = 3.2
P. robustus = 3.2
Give an example of non-primates using tools.
Egyptian vultures use rocks to open eggs.
They aren’t manufacturing tools but they’re using them.
A tool is the extension of your __________.
A tool is the extension of your phenotype.
When was Homo habilis around and where were the first fossils found?
1.9-1.6mya
The first fossils were found in Tanzania
Who made oldowan tools?
Not sure because they were found in places where Homo and Paranthropus were both living.
Explain how oldowan tools are made.
Use two cobbles to knock off some flakes and then you have some left over core and some flakes. The flakes were what were used.
Initially, people thought the core of the Oldowan tools were what was important but later discovered it was the flakes. How did they discover this?
The microwear showed that the cores weren’t actually used much but the flakes were.
The flakes are more useful for cutting.
Hominins had most likely been using tools before the Oldowan tools but why can’t we see this in the fossil record?
They would have been made of wood or would have been using unaltered rocks.
Altered tools show more advanced tool use.
Describe the teeth of Homo habilis
Smaller teeth than Paranthropus (but Paranthropus was megadont)
Incisors and canines small. Small incisors occur convergently in Homo and Paranthropus.
Short palate and dental arcade
More evenly curved parabolic tooth row
Mandible small and lightly built in males, thicker in females
Why was Homo habilis called such?
Habilis means dexterous or good with your hands. So they called it habilis because they thought they were making tools and their hands looked just like ours, very few differences.
Describe the cranium of Homo habilis.
1) 550cc
2) Thin cranial bones
3) No sagittal crest like in Paranthropus
Reduced prognathism (happens convergently in both Paranthropus and Homo)
Describe the postcrania of Homo habilis.
1) Long and robust arms (arboreality)
2) human-like thumb joint
3) Long, curved fingers (arboreality)
4) Tibia and fibula human-like but short
5) Foot arch not well-developed (so walking not the same as in humans)
6) Sexual dimorphism: males 40kg and females 25 kg but depends which individuals you class as habilis.
Describe Homo naledi.
1) Rising Star Cave, South Africa, not sure of date
2) About 1500 bones
3) Cranium, mandible dentition like Homo but brain size in Australopithecus range
