The proportion of energy transferred from one trophic level to the next is known as trophic level transfer efficiency or ecological efficiency. The Ten Percent law states that 'net production at one trophic level is generally only 10% of the net production at the preceding trophic level'. In this example, the producer contains 6000 units of energy. 10% of this will be transferred to the primary consumer, i.e. 600 units. In turn, 10% of this energy will be transferred to the secondary consumer i.e. 60 units.
<h2>540 million years ago
</h2>
Paleozoic.
Era immediately follows Precambrian It lasted about 4.5 billion years.
When did abundant fossil evidence first appear in the geologic record.
540 million years ago.
Because the snails blend in with the light filled environment which allows them to blend in
