Other than being a pretty mundane version of the argument from incredulity, it's misinformed. There's plenty of indication, fossil and otherwise, of pre-Cambrian multicelluar life, not just algae and bacteria; although the evolution of life with hard parts did occur in the Cambrian, along with pretty massive diversification.
The rest of the arguement is pretty tiresome variations on "it just seems soooo unlikely". Who cares what "seems unlikely"? We're working with time spans and processes outside the realm where our intuitions are reliable.
[This message has been edited by Zhimbo, 08-11-2003]
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