• A chemical evolution produced the first cell(s).

1. What type evolution produced the first cells?
   Answer

Essential Study Partner

• Origin of Life

• All living things are descended from the first cell(s), and therefore they share a cellular structure and a common chemistry.
• Darwin gathered evidence for common descent and proposed a mechanism for natural selection.
• The process of natural selection accounts for the great diversity of living things.

1. What is biological evolution, and what are its two most important aspects?
   Answer
2. What type evidence convinced Charles Darwin that biological evolution does occur?
   Answer
3. What process accounts for the great diversity of living things?
   Answer

Essential Study Partner

• Before Darwin
• Voyage of the Beagle
• Natural Selection
• Evidence for Evolution
• Concept Quiz

• Humans (Homo sapiens) are in the order Primates, which are mammals adapted to living in trees.
• Primate characteristics include an enlarged brain, opposable thumb, stereoscopic vision, and an emphasis on learned behavior.

1. How are humans classified – from domain to species?
   Answer
2. What are the characteristics of all primates, and how are primates related to one another?
   Answer
3. What features are used to distinguish hominid fossils from ape fossils?
   Answer

Essential Study Partner

• Primates

• About 3 mya, several species of australopithecines (the first hominids) evolved in Africa . The australopithecines had a small brain, but they walked erect.

1. Why are australopithecines, living about 4 – 3MYA, thought to be hominids?
   Answer

• About 2 mya, Homo habilis, the first hominid to make tools, was most likely a hunter, and may have been able to speak.
• About 1.9 to 1.6 mya, Homo erectus migrated out of Africa and was a big-game hunter that possessed fire.
• The out-of-Africa hypothesis says that modern humans evolved in Africa, and after migrating to Europe and Asia , they replaced any Homo species there, including the Neanderthals.
• Cro-Magnon is the name given to modern humans who made sophisticated tools and definitely had culture.

1. How might Homo habilis , living about 2 MYA, have differed from the australopithecines?
   Answer
2. How might Homo erectus , living about 1.9 to 1.6 MYA, have differed from Homo habilis ?
   Answer
3. What is the out-of-Africa hypothesis and what bearing does it have on the evolution of humans?
   Answer
4. How does Cro-Magnon, the first of the modern humans, differ from the other species in the genus Homo ?
   Answer

Essential Study Partner

• Hominid History
• Concept Quiz