Thursday, October 21, 2010
Science Time Line of Life on Earth!
To kick off our biology unit in science this year we have been doing a lot of work learning about different theories of how life has developed on Earth. We are collaborating with the other islands schools in science this year and got the great idea from the Islesford school to create a large tim line of the existence of life on Earth.
First we did our research and figured out that life has been on Earth for about 3.5 billion years and many scientists have broken that time up into 12 distinct periods. The kids had to first figure out how long each period lasted and then do some research into to what types of life forms where on Earth during that time. They also looked into the conditions of Earth throughout each period and what/if any natural disasters were occurring on Earth during that time period.
Once they had the research done it was time to start figuring out how we were going to make this darn timeline.
We wanted to timeline to go around our room, so we measured two of the walls to figure out the perimeter.
Then we had to figure out the ratio of how many years one-inch of our time line was going to represent. After calculating we figured that one inch of our timeline would equal 2,806,736 years! HOLY MOLY!
With this information we were able to figure out how many inches each period of our timeline would be. We began measuring out pieces of paper to represent each of the 12 periods.
The amount of measuring, calculating, and rounding that went into the process was AWESOME!
When it was time to measure the last period, the Quaternary Period, we were so blown away by how small this period was.
Out of the 1,247 inches of our timeline, only .64 inches represented the Quaternary Period! This is the period when humans first appeared on Earth... but the time we have been on Earth is only represented in the last .04 inches of our time line!!! CRAZY!
And as Quinn so solemnly stated, "We (humans) have only been on Earth for about 8,000 years out of the 3.5 billion life has existed and yet we are the ones who are doing the most damage and destroying it." Something to think about.
We had to redo the Tertiary Period because of some faulty measurements so Maya helped to get rid of our scrap paper.
The next step was to color coat the different periods. So it would be easy to understand the different lengths of the periods when we hung the timeline on the wall.
Dark Blue represents the Pre-Cambrian Period. Which is the first and LONGEST period of life on Earth! It lasted 2,950,000,000 billion years! It takes up 1,051 inches of our timeline!