Under Your Feet

47

Fossils are the traces (such

as footprints) or remains in

rocks of living things from

millions of years ago.

Sizing it up

Soil particles come in different sizes.

Imagine a clay particle as a large

coin. Next to it, silt would be as big

as a tennis ball, and coarse sand

the size of a hot-air balloon!

Sand particles

look like very

small rock pieces.

Both plants

and animals can

become fossils.

The best soil for

plants has not

too much sand

or clay.

Clay particles

look like tiny,

flat plates.

Plant food

Soil is made up of

sand, silt, and clay

particles. The amount

of each affects how

fertile soil is, how

much water it holds,

and how well water

drains through it.

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046-047_Rocks_And_Minerals.indd 47 31/10/2019 14:05