1. Summary

This video explains how humans did not magically appear on the Earth. The evolution of humans did not occur at one specific point. Instead they slowly changed from a fish 375 million years ago to the modern humans today.

2. Why Watch This Video?

1. Have you ever wondered how the human species developed?
2. Would you like to know the process of how humans evolved into modern humans?
3. Have you ever been confused by evolutionary relationships?

3. Key Terms

• Species: A group of creatures that can produce reproductive offspring. This means that a member must be able to mate with another member and produce babies that can have babies.
• Evolution: Every time one member of a species is born, they have a small change in their physical structure. This change can be very small and may not be noticed until it continues to change in that species ancestry line. It can then be physically observed. The time for this physical change to occur varies.
• Fossil Record: a timeline of life throughout history based on the remains left behind by previously living things.

4. Loose Ends

Loose end #1: The tree he is talking about is known as the phylogenetic or evolutionary tree. This is simply a diagram that shows how species are related to each other and have evolved over time. They show that species do not have a sudden specific origin, but rather come to be slowly over time. You may have made a family tree in the past which is an example of phylogenetic tree on a small scale.

Loose end #2: Evolution does not happen overnight but rather takes generations to show physical signs of change. There are only small changes in every generation instead of one large sudden change.

Loose end #3: There is no first humans because humans have evolved just like all other species in the world to one specific ancestor. This ancestor is a tiny cyanobacteria which was a prokaryote. From this life form all other life on earth evolved. That is why Earth’s history is much older than humans. Humans are still a new species on Earth that took millions of years to evolve.

5. Self-Test