Page 140 - The Cambrian Evidence that Darwin Failed to Comprehend
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The Cambrian Evidence That Darwin Failed to Comprehend
seas of 530 million years ago, they were prolific and are commonly
found in fossil beds. They also present one of the greatest disap-
pointments facing Darwin and his supporters in later years, and one
of the greatest problems they need to overcome.
As we mentioned before, with few exceptions, soft tissues are
seldom preserved because they represent food for predators. Also
bacteria are microscopic predators, ready to decay tissues as soon as
organisms die, wherever they may be. They feed on such organic
substances throughout their lives. 100
That is why we cannot obtain complete knowledge of how an
extinct life form lived, which organs it used for what purpose, or the
structure of those internal organs. Only the fossil remains they have
left behind can give us any information to learn about them and un-
derstand the general systems they possessed.
Yet when it comes to Cambrian life forms, the picture is very
different. In the great majority of cases, these creatures’ soft tissues
have been so well preserved that we can establish how they lived
and fed, whether or not they were predators, and whether they were
fast swimmers. Trilobites were invertebrates that lived in various
parts of the world and have left behind the greatest number of tra-
ces from the Cambrian Period. For that reason, by comparing all
these specimens, it has been possible to reconstruct their lives in
considerable detail.
Trilobites represent a subphylum of the phylum Arthropoda.
Their hindparts were divided longitudinally into three lobes (which
is where the name trilobite comes from). A shell made of keratin cov-
ered their head and body. Like present-day arthropods, these crea-
tures grew by molting, or shedding their shells. In sheer numbers,
trilobites represent more than half of all Cambrian fossils, and their
shells have been exceptionally well preserved. With their detailed
body structure and their perfectly developed form, sensitive nerv-
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