Page 108 - The Cambrian Evidence that Darwin Failed to Comprehend

The Cambrian Evidence That Darwin Failed to Comprehend

Marrella
Marrella, described as a “lace crab” by Charles Walcott, is one of
the most abundant of Burgess Shale fossils. Some 15,000 specimens
of Marrella have been collected from Walcott Quarry (named after
Walcott) alone. We have a three-dimensional knowledge of just
about all this invertebrate’s features. Marrella’s head shield had two
pairs of rearward spines that were sufficiently long to extend right
along its body. It had two pairs of antennae. One of these was an ex-
tension consisting of short segments. The other had a brush-like
end.
Marrella’s body was composed of increasingly small trunk seg-
ments, each of which had a pair of legs. The antennae of this crea-
ture, which is thought to have fed on organic matter and small or-
ganisms, were probably used to gather up these small elements from
the sea floor. The feathery filaments on the outer branch of its legs
were used for respiration. 71

A reconstruction of fossil Marrella
A fossil Marrella

Canadaspis
Canadaspis fossils have been preserved with nearly all their fea-
tures. The animal’s carapace had two valves literally hinged togeth-
er. The abdomen, thorax, and intestinal system are completely visi-

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