invertebrate evolution

When Did The First Invertebrates Evolve?

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When Did The First Invertebrates Evolve? About 3.5 billion years ago, the first microscopic organisms appeared in the ocean. The first invertebrates developed in the oceans. They were soft-bodied animals with a shell or carapace, such as these trilobites. What were the first invertebrates to evolve? Sponges represent the first organism at the multicellular stage

What Is The Evolution Of Invertebrates?

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What Is The Evolution Of Invertebrates? It was the first step in the evolution of organs and organ systems. At first, invertebrates developed tissues from just two embryonic cell layers. There was an outer cell layer called ectoderm and an inner cell layer called endoderm. The two cell layers allowed different types of tissues to