Ardi weighed about 50 kg (110 ib) and could be up to 120cm (3ft 11in) tall.

Dated to about 4.4 million years ago.

Although she was a biped, Ardi had big toes and thumbs in order to climb trees.

It's speculated that her bipedality impeded movement, but enabled her to bear more offspring.

Regarded as the oldest human anthropoid.

1 of 8


Lucy was an early australopithecine and is dated to about 3.2 million years ago.

She was smaller with longer arms.

Had a sloped forehead.

The skeleton presents a small skull plus evidence of a walking-gait that was bipedal and upright.

This combination supports the view of human evolution that bipedalism preceded increase in body size

2 of 8

Earliest to modern:


Homo habilis

Homo erectus

Homo sapien

3 of 8

Rocks and tools:

Tools provide evidence for human evolution. Primitive tools(first hand axes) have been found in remains from the Palaeolithic Age (10,000 to 2.5 million years ago). Tools have been dated from the environments they were found in. This is often the layers of sediment surrounding the tool- stratification. Dating can be done by radiocarbon dating or other techniques which look at the amounts of elements like iron or potassium. Leakey was the first to link the layer with the tool found there. It is assumed that the tool is approximately as old as the rock which surrounds it.

4 of 8

Summary- how stone tools evolve:

Over 2 million years ago, promitive humans were using large, round stone choppers and hand axes, hand sized rocks with one end flaked into a sharp edge or point.

Used for cutting meat and scraping skins to chopping wood and digging hole; building shelters and homes.

Later triangular points, probably used as knives.

They aslo figured out that fixing a stone implement into a handle (or haft) of bone or antler gave them better leverage.

5 of 8

how did scientists work out the ages of stone tool

The rock layer in which the tool was found determine their age. The top layer of any rock indicates younger tools, while the tool found deep down indicated older ones.

6 of 8

why was the size of skull important for scientists

It determined the age and development of early humans. In astralopithecus, the skull was smaller while in homo sapiens the skull was bigger. Smaller skull meant smaller volume of brain and less sophisticated tools were around such as large round rocks. While larger skull has bigger volume of brain and more sophistication and advanced technology such as sharp edged rocksused to build shelters and cut meat.

7 of 8

The 5 kingdoms:






8 of 8


No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Evolution, extinction and natural selection resources »