Eurasion Fossil Apes Lecture 8

Question 1

Name and describe the specimen formerly known as Sivapithecus

Answer 1

Ankarapithecus meteai

1) Turkey
3) 15.5 mya (Miocene)
4) Dental and cranial remains

Question 2

Why is Ankarapithecus meteai thought to be related to orangutans?

Answer 2

They have incisor heteromorphy with the I2 being much narrower than the I1. Amongst the apes that are alive today, the only ones that have incisor heteromorphy are orangutans.

Question 3

Describe Rudapithecus

Answer 3

1) Hungary

2) About 10mya (Miocene)

Question 4

Why is Rudapithecus thought to be related to extant apes?

Answer 4

1) Has a moderate brow ridge (like in extant apes)
2) The end of the humerus has an articulation for the radius and ulna (called the trochlea). Most other mammals don’t have this indentation but apes have a pronounced trochlea.

Question 5

Describe Lufengpithecus

Answer 5

1) Late Miocene of China
2) Approx 50kg but two sizes present; sex dimorphism or separate species?
3) If they are sexually dimorphic then they are the most sexually dimorphic (more so than extant species; today gorillas are most sexually dimorphic in hominoidea)

Question 6

Name the largest primate that ever lived and describe it.

Answer 6

Gigantopithecus

1) Late Miocene-Pleistocene, India/China
2) Really large molars - megadont or just really big? e.g. from the teeth of pandas you would guess they were double the size they actually were.
3) Dental remains only (postcrania would be most useful for determining size)

Question 7

What are phytolyths?

Answer 7

Phytolyths are crystals that form inside plants and the shape of phytolyths are specific to the plant species.
Sometimes plaque has phytolyths in it so you can tell what the animal was eating.

Question 8

Why might Gigantopithecus be megadont?

Answer 8

They found phytolyths specific to bamboos, so maybe they are megadont since pandas eat bamboo and they are megadont.

Question 9

Describe Oreopithecus.

Answer 9

1) Italy, 6-7mya (Miocene)
2) Complete but crushed
3) Fully suspensory postcranium
4) Potentially bipedal

Question 10

In what ways does Oreopithecus have a suspensory postcranium?

Answer 10

1) Ulna doesn’t contact carpals
2) Short lumbar spine
3) Long clavicle

Just like apes!

Question 11

Why do some people think Oreopithecus might be bipedal?

Answer 11

Pelvis is very similar to Homo sapiens. But if it was bipedal it would have been arboreal too due to curved phalanges. They had long arms so this would tie in nicely with bipedal and arboreal.

Question 12

Exmplain why Ouranopithecus is thought to be related to people? Why might this not be true?

Answer 12

1) Lived in a terrestrially in open environment (like people)
2) Less sexual dimorphism in canine teeth than gorillas and orangs, like people though!

AGAINST

1) Theropithecus was in an open environment and didn’t look anything like people
2) Could just happen to have less sexual dimorphism

Question 13

Which ape do we have hardly any fossil evidence of?

Answer 13

Gibbons: just a few teeth and some species that are young (only a few thousand years old)

Question 14

Describe Sivapithecus.

Answer 14

1) Asian 13-8mya (Miocene)

2) Dental, cranial and postcranial remains

Question 15

People have narrower ______ ________ compared to other apes

Answer 15

People have a narrower ANTERIOR PALETTE compared to other apes

Question 16

What are the two morphologies of subnasal morphpolgy in extant apes?

Answer 16

1) Stepped subnasal overlap in African apes

2) Smooth subnasal overlap in Orangutans

Question 17

What kind of subnasal morphology did Sivapithecus have?

Answer 17

Smooth subnasal overlap

further evidence for it being more closely related to apes

Question 18

Name three features seen in Sivapithecus that is similar to orangutans?

Answer 18

1) The I2 is smaller than the I1
2) Narrow interorbital distance in orangs and Siva
3) Orbits are taller than they are wide
4) Canine implantation: long axis of canine teeth slightly at an angle to the rest of the tooth row

Question 19

Which part of Sivapithecus does not support it being a relative of orangutans?

Answer 19

The postcrania:

Siva humerus is retroflexed so the head of the humerus faces posterially and dorsally

Question 20

What does putting Sivapithecus and orangutans in a clade together imply?

Answer 20

Most analyses are putting pongo and siva in a clade together  implies living hominoids have evolved their postcranial morphology convergently or that apes developed suspensory morphology early on and siva has reversed that and gone back to being a quadruped.

Other possibility: having siva face morphology is ancestral condition of all hominoids and Gibbons have gone back to this ancestral morpho

Question 21

In the beginning of the Miocene, most of the catarrhines are _______ but through time that percentage goes down. This looks like it is due to _______ in Africa.

Answer 21

In the beginning of the Miocene, most of the catarrhines are apes but through time that percentage goes down. This looks like competition in Africa.