Human OriginsHuman Originsinin

AfricaAfrica

About 3.6 million years ago, a couple of hominids of the species we call Australopithecine went strolling through some volcanic ash. Their footprints were found in 1978.

• What was remarkable about these footprints?

• Well, two feet, no knuckle marks, a big toe, and an arch. These people were walking upright (which is what a hominid is).

• Also, in 1974, the fossilized remains of “Lucy” were discovered. She was nearly 3.2 million years old. The bones also indicated she walked upright.

• So what’s so special about walking upright? Well, it has some advantages:

• Hands are free while walking, allows for better visibility, it’s extremely energy efficient.

• The downsides are that you might be slower and it makes childbirth much more difficult and hazardous.

The top ones are female and male modern humans. The bottom one is a chimpanzee pelvis.

Man, gorilla, chimpanzee, orangutan, gibbon

As time went on, hominid skulls and brains got bigger.

• Good thing because humans are pretty pitiful physically. It’s our brains that make us dominant.

• The brain size of Australopithecus was about 500 cubic cm. We have about 1,400 cubic cm.