One Amazing Substance - Andrew Franck | Library

INSTRUCTIONS: Answer the following questions related to the BBC Earth article:
http://www.bbc.com/earth/story/20151205-one-amazing-substance-allowed-life-to-thrive-on-land 
(Note: Refer back to the website if you are having difficulty).

3

Justify the author's statement "soil is crucial to almost every aspect of life and land" with three specific pieces of evidence from the article.

2

What date does the author give for how long ago soil began to develop on Earth?

4

What two factors allowed the conditions on Earth to stabilize and marked an important turning point for soil development?

2

It is believed that the earliest soil did not hold water or nutrients well and thus was not a friendly host to support life. What organisms does the author give credit to for creating soil that supported life?

2

Plants were able to move to land because of their symbolic relationship with what organism?

2

Soil has been slowly evolving for billions of years, but the author warns that human actions are destroying soil resources at a much faster rate. What does the author list as the major threat to soil in our society?

7

Create a timeline for "The Evolution of Soil on Earth" by matching each development with the correct time period.

Draggable item		Corresponding Item
Plant life moved to land along with the mycorrhizae fungi in their root systems, adding more organic matter and nutrients to soil.		4.6 billion years ago
Liquid water formed and began to weather the rocks. This was the first step towards soil formation.		3.8 billion years ago
The structure and composition of soils present at this date were very much like those of the soils we have today.		3.5 billion years ago
Lichens appeared. As they lived and died, they changed the makeup of soil by producing acids that increased the weathering of rock, contributing organic matter to soil composition.		700-550 million years ago
Clay-rich rocks developed on Earth as temperatures cooled. They were frequently pummeled by meteors and broken into smaller pieces.		440 million years ago
Land animals emerged, further increasing the organic matter in soil. Some land animals evolved to live within the soil, greatly impacting soil structure.		490-430 million years ago
Life appeared on Earth, and organic matter that built up on the shoreline mixed with the weathered rocks, forming the first true soil.		360 million years ago