Worldwide distribution of hominin fossils (9)

Question 1

Which continent is where Homo fossils are found earlier than 2 mya?

Answer 1

Africa is the only continent where Homo fossils earlier than 2 mya have been found. Later homo fossils from about 2 mya to recent times have been found in Africa, Asia and Europe.

Question 2

Which two African sites have many early hominin (Ardipithecus, Australopithecus and Homo) fossils been found? (2)

Answer 2

These areas are:

1. East Africa, in the Great Rift Valley,
2. South Africa, particularly the Cradle of Humankind.

Question 3

How long is the Great rift Valley and which countries is it found in?

Answer 3

The 2 000-kilometres-long Great Rift Valley is a very distinctive and dramatic geological feature in East Africa (Kenya and Tanzania) and Ethiopia.

Question 4

The rift opened up approximately __ million years ago, shortly after the _________ became extinct. The very steep sides of the rift valley produced a lot of ________.

Answer 4

65
dinosaurs
sediment

Question 5

How does sediment cause hominins to become fossilised?

Answer 5

This sediment landed in the rivers and lakes where hominins or their remains became trapped and eventually fossilised. The sediment formed a number of layers of sedimentary rock or beds many of which contain fossil hominins.

Question 6

Where are the hominin fossils usually found?

Answer 6

These sites have produced a greater variety of fossil hominins than anywhere else in the world. While the fossils are largely found in the sedimentary rocks, hominin traces, e.g. footprints, have been preserved in ash from active volcanoes.

Question 7

What are the Sterkfontein, Swartkrans and Kromdraai apart of?

Answer 7

Cradle of Humankind Sterkfontein, Swartkrans and Kromdraai are part of a set of about 500 limestone caves of special interest to palaeo-anthropologists as they are among the most prolific fossil sites in the old.

Question 8

Where is the Sterkfontein caves situated?

Answer 8

Sterkfontein was declared a World Heritage Site in 2 000 and the area in which it is situated was named the Cradle of Humankind. It lies in Gauteng province the near town Krugersdorp.

Question 9

What are the Sterkfontein caves made of?

Answer 9

The Sterkfontein fossils are found in limestone caves embedded in a mixture of limestone and other sediments called breccia that fossilised over time. This is unlike the East African fossil sites, which are laid down in beds

Question 10

Define Breccia.

Answer 10

breccia = a rock type formed from mineralised sediment

that has fallen into caves

Question 11

What artefacts tell us more about life around caves?

Answer 11

It is from the breccia that fossil bones, plant remains and stone tools (artefacts), which tell us about life around the caves from 3.5 to 1.5 mya, have been (and are still being) excavated.

Question 12

How many fossils have been found at the Sterkfontein caves?

Answer 12

About 500 hominin fossils have been found at Sterkfontein. This represents about 40 percent of all hominin fossils found so far making it the richest site in the world for finding ancestors of modern humans.

Question 13

How was it discovered that early hominins did not live in caves?

Answer 13

It seems that early hominins did not live in the caves; their remains probably were dropped by leopards from kills stored in trees or washed into the cave with rains, the bones becoming preserved within the breccia.

Question 14

Why were the fossils disarticulated?

Answer 14

Most of the fossils are disarticulated because the hominins were either partly eaten or because porcupines dragged the hominin remains into the caves. The animals chewed the bones to sharpen their continuously growing teeth.

Question 15

Name 5 important fossil and archaeological finds in the Cradle of humankind

Answer 15

1. Humankind The first adult Australopithecus - Mrs Ples (2 to 3 mya).
2. The only almost complete Australopithecus skeleton – Little Foot.
3. The oldest stone tools from the Oldowan culture indicating that Homo habilis might have lived in the area. 4. The largest number of Australopithecus africanus fossils.
4. A new fossils species announced in 2010, Australopithecus sediba that has a mix of primitive features typical advanced of more australopithecines and characteristics typical of later hominins.

Question 16

What does “Maropeng” do?

Answer 16

Maropeng, the visitors’ centre of the Cradle of Humankind tells the story of the origin of humankind, and their continuing journey into the future. Maropeng means ‘returning to the place our origins’.

Question 17

Why are the Cradle of Humankind fossils so important?

Answer 17

While the Cradle of Humankind fossils have already told us many, many things about our pre- history, new findings will teach us even more. So far, from these fossils, we have learnt the following important aspects about human evolution.

Question 18

How long ago did an early ancestor of the Homo sapien in South Africa exist?

Answer 18

An early ancestor of H. sapiens existed in South Africa Between 2 and 3 mya years ago a 1.3 m tall hominin with a blend of ape and human characteristics lived on the Gauteng Highveld.

Question 19

Which hominid may of been an ancestor of our own genus?

Answer 19

The ape-man (Australopithecus africanus) may well have been the ancestor of our own genus, Homo. Australopithecus africanus seems to be endemic to South Africa as no remains of this species have been found anywhere else in the world supports the Out of Africa hypothesis.

Question 20

What caused evolutionary pressure on the ape-man?

Answer 20

The climate changed between 2 and 3 mya which put evolutionary pressure on the ape-man. As a result between 2 and 2.5 mya years ago speciation occurred and the ape-men started king on different characteristics that eventually would lead to two separate species.

Question 21

Name the two species that started to loom like the earliest members of our own species (2)

Answer 21

One with a flatter face and larger teeth, a robust ape-man, Parathropus robustus and another, Homo habilis that started to look like the earliest members of our own species.

Question 22

What happened 2 mya?

Answer 22

Around 2 mya Australopithecus africanus disappeared from the fossil record and the two ‘new species co-existed for hundreds of thousands of years, using basic tools and living in different ecological niches.

Question 23

What tools did these two closely related hominin species co-existed in South Africa (P. robustus and H. habilis)?

Answer 23

P. robustus possibly used bone tools and was vegetarian while H. habilis used stone tools and had a varied diet that included meat different ecological niche and plants.

Question 24

What might of given H.Habilis an advantage?

Answer 24

Meat may have given H. habilis an advantage as its brain could have developed further helping it evolve into the Homo line that exists today.

Question 25

What hominin genus became extinct 1 mya?

Answer 25

The robust Paranthropus species, while living for about 1 million years became extinct 1 mya.

Question 26

What caused the extinction of robust Paranthropus?

Answer 26

It is not known what caused this. It could well have been direct competition with Homo, which was becoming skilled in extensive bone and stone technology, or it could have been a variety of other issues, including a slower reproductive rate.

Question 27

What new species started to emerge 1.5 mya and what evidence was there for this?

Answer 27

By about 1.5 mya a new species started emerging, African H. erectus (H. ergaster). The evidence of this is the more sophisticated stone tools, e.g. million-year-old hand axes at the Gladysvale and Plover’s Lake sites.

Question 28

What did improved tools show and result in?

Answer 28

The improved stone tools showed evolution of the brain. In turn it enabled these hominins to catch fast moving prey and thus live in the harsh, drier African environment.

Question 29

About __ million years ago the climate became drier and the forests in Africa started _____. This environmental change brought new selection _________. Any ape-like beings that could walk _______ and move easily across the open areas with fewer trees were selected for ______ as they could ______ better to the new environment.

Answer 29

20 
shrinking
presures 
upright 
survival 
adapt

Question 30

What is considered a major feature that enabled ape-like men to evolve and what other qualities arose from it?

Answer 30

Bipedalism is considered the major feature that enabled ape-like men to evolve into modern man. From this arose the development of the other qualities language and culture.

Question 31

What did bipedalism enable?

Answer 31

The upright stance freed the hands, which made possible a variety of new activities such as carrying and tool-making. The initial tools, in stone, were made by Homo habilis.

Question 32

What did tools enable homo habilis to do?

Answer 32

With these tools they could successfully collect (scavenge) meat from animals killed by other animals. The extra protein acquired this way helped with the development of the brain, which over time led to the making of more diverse and sophisticated stone tools by the hominins. This enabled them to change from scavenging to hunting.

Question 33

What else did these hominins do?

Answer 33

At the same time these hominins discovered the use of fire. This led to great changes in their way of life. Fire hearths lead to the development of integrated groups living in camps which stimulated co-operative behaviour, e.g. organized hunting, which needed technical skill, planning, division of labour and a simple system of communication which later developed into speech.

Question 34

What did social living and a more complex brain enable?

Answer 34

Social living and a more complex brain, the capacity of which increased over time from about 775 cc to 1225 c, lead to more complex behaviour which led to the development of the human cultures such as clothing, the building of shelters, rock engravings and paintings and religious rituals surrounding the burial of the dead.

Question 35

What additional changes did fire led to?

Answer 35

Fires also led to another important change. Diet such as fire-making, tool-making, switched from raw to cooked food with more extensive meat-eating. It is commonly agreed that cooked food yields more nutrients resulting in further development of the cerebrum.

Question 36

Thus what are bipedalism, fire making, tool-making, language and culture?

Answer 36

These characteristics are all interdependent and increased the hominin’s ability to adapt to and to modify their environments.