If you rub your finger across the body of an earthworm, you may notice little ripples. earthworms were among the first organisms to display

The correct answer is: segmentation.

Segmentation is the fact that some animals and plants have parts of the body that are divided into segments, which typically have a similar structure (they are then called repetitive segments).

Humans also have a segmentation, for example in their spine.

The atmosphere wasn’t strong enough to contain more oxygen when compared earths atmosphere today, the exosphere was full of rips and couldn’t contain enough oxygen to provide for land creatures, although aquatic earthlings could continue i exist in this environment