| 21. | The mountain is formed with quartzites and metamorphosed slates of the Proterozoic Eon and Cambrian Period.
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| 22. | Sutures are found in animals with hard parts from the Cambrian period to the present day.
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| 23. | It preserves trilobite fossils from the Cambrian Period.
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| 24. | Lyrarapax " "'is an anomalocaridid that lived in the early Cambrian period 520 million years ago.
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| 25. | It is the most long-lived anomalocaridan clade, lasting from the Cambrian period to the Devonian period.
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| 26. | The earliest probable species of tunicate appears in the fossil record in the early Cambrian period.
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| 27. | It is an ancient group, with fossils dating from 530 million years ago, in the Cambrian period.
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| 28. | Oxygen levels seem to have a positive correlation with diversity in eukaryotes well before the Cambrian period.
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| 29. | These first appear after the boundary between the Proterozoic and Phanerozoic eons or Ediacaran and Cambrian periods.
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| 30. | They lived during the Middle Cambrian period.
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