[balrog666]

There are over 40 phyla that arose during the Cambrian - none, zero, nada after it.

And you "know" this how?

For the record, we "know" of several surviving phyla that appear to have arsien long after the Cambrian. Also, we simply do not know how many "phyla" arose pre-Cambrian as we know only the survivors and those few that left unambiguous fossil records.

There may be many additional survivors we don't yet know about and almost certainly we will discover more pre-Cambiran phyla precursors that got edged out in the competition to survive.

[gore3000]

There are over 40 phyla that arose during the Cambrian - none, zero, nada after it.-me-

And you "know" this how?

The way most people learn things. I read.