How did O2 levels affect the size of living things? Also, what have humans recently used the vegetation from this time period for?

sand 60

clay 10

silt 30

sandy loam should be dominated by the sand. as the amount of sand increased, the amount of slit needed to anchor the plants' roots to the sand will also be increased. even though the amount is very little, 10% part of clay is still necessary for proper oxidation.

answerblank(1); ecological; blank(2); evolutionary;