It appeared that in 5-10 million years,
ancestors of all but two of living phyla came into being.
(The two phyla are Bryozoans, whose fossils can
only be dated back to the Ordovician era, and a small creature recently
discovered growing on lobster lips.)
With current work on rocks in Russia and Namibia that bracket the boundary, soft-bodied ancestors to some of the Burgess shale fauna have been found. Now the 5-10 million year "explosion" has been revised to a 35-40 million year period of rapid diversification.
The painting above shows animals from the Changjieng fossil fossil beds. It is an example of a Burgess shale-type community that is younger than the Burgess shale fossil beds (~510 Ma).
Detail of p painting by D.W. Miller from American Scientist, March-April, 1997. Labels added