Conway Morris found that the shelly fossils in Walcott's Phyllopod Bed were about as abundant as in other shelly fossil deposits, but accounted for only 14% of the Phyllopod Bed fossils. Assuming that, as in modern marine ecosystems, about 70% of the species that lived in the Early Cambrian seas are unsuitable for fossilization, he estimated that the shelly fossils probably represent about 2% of the animals that were alive at the time. Since these shelly fossils are found in other parts of North America and, in many cases, over a much wider range, the Burgess Shale fossils, including the soft-bodied ones, probably show how much diversity could be expected at other sites if Burgess Shale type preservation were found there.[31]