ANTA01 Introduction to Anthropology
Lecture 5 Human Beginnings
Wants us to understand what a Hominoid is and what is a Hominins.
We are starting at Myocene in this class.
We see branching off of more of primitive forms as we go through time.
The new world is North and South America and the old world is Europe and Asia.
Hominoids include most of the apes.
Who are Hominoids & Hominins
Hominoids are the greater and lesser apes.
Hominins is a subgroup of hominoids including humans, pan, & and ancestors that we share.
Hominoids include humans, chimpanzees & bonobos, gorillas, orangutans, and the gibbons.
A definitive way of identifying hominoids is they have y5 cusp pattern in teeth.
Hominoids are very big compared to other species.
Hominoids lack tails.
The dental formula reflects the number of teeth in the mouth. Mouth is made up of 4 quadrants. Each
of us has 2 incisors, a canine, 2 premolars, and 3 molars. In humans we have a 2,1,2,3 pattern in each
Humans and all other hominoids have a 2,1,2,3 dental pattern.
Most walk on four legs and anatomy will reflect this.
On the bottom of our humorous is a capitulum, a round ball that allows lower part of radius to twist.
We are similarly related to other Hominins and we only pick up differences through evidence of
What can we find specifically in the fossil record to know we have a hominoid? You look specifically
for the teeth.
You are going to look for the humorous and the capitulum.
And also look for the fact that humans and other hominoids do not have tails!
When we are hunting fossils, we are looking for skull, upper arm bones, and evidence of being
98% of our DNA is shared with chimpanzees, so bipedality is the main way we differentiate between
hominins vs. hominoids.
Primarily looking at East and South Africa to find fossils.
Pick up bipedality by looking at specialized locomotion.
On the left at the top is a picture of the gibbon which has long arms and hooked fingers, they do
breakiation where they put one hand in front of the other to move. They have had various aspects of
their anatomy to change, they have short back, long arms, and curved fingers.
Bottom left is the picture of a chimpanzee walking on his knuckles. This applies to the chimpanzees
and the gorillas, they have a specialized form of locomotion but maintain quadropedal aspect.
In the middle is the fossil of an orangutan, whose feet are as grasping as hands are, they move
momentum to move through the forest, but bigger males shuffle on the ground as too big to move in
trees. The last picture is humans. Our pelvis has changed because we are now upright. Our leg has
transformed in order to maintain balance. now the brain stem meet brain at the base of the skull
instead of the back.
Foramen magnum is signaled by the red dot. It is the large hole at skull where brain stem meets
The position of foramen magnum comes forward in the skull to maintain balance.
The pelvis now has to hold up all of our guts, whereas apes back hold all of their weight. Our pelvis
becomes low, round, and flared.
There are 3 things that happen in femur of human vs. ape.
o The femur angles in, the knees come together.
o There is a round head on the top of the femur that gets bigger to support our weight.
o The length of the neck of ball of femur and shaft of femur gets shorter.
Humans have an extra lumbar vertebra that other species do not have. None of the other hominoids
have curvature of the lower spine.
When we find specimens, we are constantly finding things we are not expecting.
The morphology of our foot has changed. Our big toe moves up in line with other toes, our heel is
elongated and we have the development of an arch.
For the past 65-70 million years the Earth has been primarily on the warm side. We are now moving
into an icy colder period. In Africa when things get cold, they get dry. There was reduction in forest
and expansion in desert. It was thought ancestors became bipedal because forest were fracturing and
they only had savannas to live in.
Most date to 5 to mya and found in both East and South Africa and a few finds in Chad.
Why are they found in East and South Africa?
o We are not expecting them to be only in East and South Africa, but in East Africa there is rift
valley that has opened up with earthquakes so you can see deposits that are 5 million years
o What drives South African economy? Mines! We have these fossils from South Africa because
we have constant mine operations digging in the ground.
Teeth are parallel to one another
They have very small front teeth and very large back teeth
Brains are only about 300 cubic centimetres
They are basically like a chimpanzee
Looks human like and found in Lake Chadd
Lucy (on the right)
o One of the most complete fossils we have.
o Found in Ladar in East Africa
20 years later they found an intact skull on the left.
They are sexually dimorphic.
The skull is of a male which is twice as large as Lucy’s was
He has flaring cheek bones
His teeth are getting bigger The space between his eyes (called post orbital constriction). It means his prefrontal cortex is very
We have horrible problems dating things in South Africas as not a lot of volcanos.
They are erect bipeds, they are not transitional but fully bipedal species.