Precambrian would have been dominant because there were so many of them. They lived in very large groups in that were known as stromatolites which were reef like in many ways.
Ferns
Jellyfish intervirbrates
Precambrian
Precambrian
Animals without backbones, called invertebrates, developed near the end of the Precambrian. Imprints of jellyfish and marine worms have been found in late Precambrian rocks. Because invertebrates were soft, they weren't easily preserved as fossils. This is one of the reasons why the Precambrian fossil record is so sparse.
The dominant organisms during the Precambrian include the proarticulatans, such as Dickinsonia, Yorgia, and Praecambridium which were a group of "air-mattress" organisms possibly related to modern day placozoans, rangeomorphs, such as Rangea, and Charnia, which were frond-shaped organisms that had bilateral to radial symmetries, and the trilobozoans, like Tribrachidium, which were disk-like organisms with a tri-radial symmetry, possibly related to cnidarians.The ancestral mollusk, Kimberellia, is found throughout Precambrian strata of the world.There were also sponges, and what have been interpreted as the polyps and medusae of cnidarians during the Precambrian, as well. Very primitive worms and arthropods appear at the very end of the Precambrian, as it transitions into the Cambrian period.
Precambrian rocks have been so deeply buried that they have changed by heat and pressure. That's a summary about the Precambrian time.
a few.
Precambrian
During the precambrian.
Males have always been dominant in Zambia.
**Precambrian**