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Course: Big History Project > Unit 10
Lesson 1: Looking Back | 10.0- ACTIVITY: Timeline Review
- WATCH: Unit 10 Overview - The Future
- ACTIVITY: Unit 10 Vocab Tracking
- WATCH: The History of Everything—TED
- ACTIVITY: DQ Notebook 10.0
- ACTIVITY: Scale
- ACTIVITY: What Do You Know? What Do You ask?
- READ: Gallery — Earth From Space
- Quiz: Looking Back
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ACTIVITY: Timeline Review
Purpose
In this course, you’ve studied the 13.8 billion years of history that got us from the beginning of the Universe to the present. In this unit, you’ll think about the future. Some of the material from Units 1 through 9 will be fresher than others, so this exercise is designed to help remind you of what you’ve learned about Big History up to this point.
Process
View the Timeline Infographic, which presents the eight thresholds of Big History as well as a sampling of key events related to each threshold. Take about 3 minutes to review the timeline and write down what you believe are the four most important events that are not thresholds.
For Further Discussion
Now that you’ve thought about some important events that aren’t thresholds, in the Questions Area below, write down two of the events that you think are most important and explain why you think that. Then, comment on the events that someone else shared – add some details that help justify why those events are so important to recognize.
Want to join the conversation?
Wow, so many to choose from, how do we narrow it down to just two? And how does certainty of their occurrence factor into the equation? Okay, I'll pick two fairly certain events, both collisions: 1.) the encounter with the Mars-sized object that created the moon, since without the moon's stabilizing function the rest of the Earth-specific thresholds would not have occurred, and 2.) the collision that created the K-T boundary, because without it (and the dinosaur extinctions that followed) the subsequent mammalian efflorescence would have been unlikely.(9 votes)
I would agree that both of those events were necessary for the Goldilocks Condition for the earth to sustain life and next for early primates to emerge after the dinosaurs died out.(1 vote)
1. 4 forces of nature just after big bang.
2. Photosynthesis
3. Eukaryotes
4. Yukatan Peninsula Meteor hit(7 votes)- I must say after reading this response, I feel my response was quite limited in scope concerning my choices to events only directly relating to myself. And "number 1" represents the foundation of science - so important to allow us to Discover and Understand Big History. Great Choice.(1 vote)
I would say that the two most important non threshold events that occurred would have to be the occurrence of photosynthesis, which allowed the plant life and other forms of life to harness the energy from the sun and create in an essence food for themselves. I think this is significant to human kind in that since we can not photosynthesis we rely on plants and various animals who eat plants to get our energy we have to consume them in order to utilize the energy they have stored. The second most important even would have to be the emergence or formation of the brain, I believe this is important because the brain not only acts as a hub for information it controls our very being and also allows for storage of information and would in teen lead to advancements towards learning language collective learning interaction and so forth. It is important that we have brains.(1 vote)
1. Domestication of the horse and learning to ride it allowed for speedy communication over long distances, especially with the use of relay stations. 2. The invention of writing, which enabled information to be conveyed, not only during our lifetime, but across centuries of time.(1 vote)- 1. Four forces of nature
2. Dinosaur extinct
3. The first brain
4. Intro to computer/internet
The first brain provides us with consciousness and reasoning. The introduction of computers/internet provides us with a limited ability to share our knowledge.(1 vote) 
The first Eukaryotes – I think this is a very huge thing for the world because if this step hadn’t taken place then there would be no humans, animals, or any other things we use, see, or interact with would be here.
First brain developed- I think this is super important because now we live of our brains, they carry all of our information and without them we would either be dumb or dead.(1 vote)- Four Important, Non-Threshold Events
1. The first brain
2. Dinosaur extinction
3. Building tools from metals
4. Introduction of Computer/Internet
The two most important events are: the development of the brain, which allows for the potential of reasoning. We find that in many species. I do believe that brain complexity provides us with consciousness, and that it is not unique to humankind, and the development of the computer and the internet which provides us with the potentially unlimited ability of sharing knowledge across such a diverse global community.(0 votes)- Agreed; the brain was an important development, and more particularly, the development of the human brain, which allows us to dream, to love, to feel a variety of other emotions, to reason, and to be aware on a much higher level than other living things. Although, I am assuming a lot here, since other living things might well be capable of much of this.
And, while the development of the computer will certainly extend our brainpower, with the possibility that we may teach it how to outsmart us; computers will never be able to feel emotion !(1 vote)
Hydrogen and helium form. Photosynthesis. Asteroid impact. Silk road.(0 votes)- 1. Extinction of dinosaurs.
2. Who thought of technology?
3. The silk roads.
4. Who thought of building and why ?(0 votes) - 1. Life on land
2. Dinosaurs and mammals appear.
3. Asteroid impact triggers extinction.
4. Hominids appear.(0 votes)