The current hypotheses that explains these trends are
This was the time that quite a number of organisms first appeared in the record of fossils.
This diversity took place over a very short period of time. This is why it is known as the Cambrian explosion.
Complete question
Animal life changed greatly during the Cambrian explosion, with some groups expanding in diversity and others declining. What are the current hypotheses that explain these trends?
A. Global climate changes.
B. Atmospheric changes.
C. Predator prey relationships.
D. Appearance of the marine top predator.
E. Changes in the regulations of develop.
F. Radiation of numerous terrestrial groups.
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