Precambrian Animals

Sometimes it's a wonderful feeling to wonder or to read about the past and by past I do not mean 100 years or 200 years ago but 4600 million years ago! That's a long time ago! Unfortunately, we have no records of these ages, so we totally have to depend on the scientists who study fossils and then unfold the past for us. Many movies have been made about these ages and it's a wonder to see how different the world was then from now. In your history classes, you have read about the Ice Age, the Iron Age and several other ages. But have you read about the Precambrian age? If yes, superb! But if no, then do not worry. Keep reading and you will find out more information mainly about Precambrian animals. It's surprising to know that some of these animals that we see around us today, their predecessors had belonged to this period.

The First Geologic Time Period of the Earth

The term "Precambrian" is the name that refers to the 4 billion years before hard bodied animals that we see around us today, were even born. This era includes Hadean period (when the moon and earth developed together), the Proterozoic period as well as the Archean period. These periods existed for 2000 years each. It was during this period that organisms like algae and bacteria or the single celled organism started originating. These organisms, they were the masters of the world that time. They developed with time and by the time the Archean period ended, i.e. during the late Precambrian period, the new Earth saw the first multicellular animals like the jellyfish (yes! Jellyfish are very old organisms), worms, moss and various other soft bodied creatures. Not only this. This period also witnessed the formation of multicellular plants which was helpful for these animals to survive as they provided oxygen. However, before multicellular animals came into existence, the world was ruled by these single celled animals. Today, we know more about these animals because of fossils. It does not give a clear picture but gives us enough information to give us a vague idea as to how old the earth is or which animals are still existing from the Precambrian era.

List of Animals in Precambrian Era

Brachiopods: They are also known as lamp shells. Once upon a time, during the Precambrian era, they had ruled the ocean. But, now, you will hardly fine one even if you visit the deepest part of the ocean. The shells of the brachiopods are different from the shells that you collect at the seaside today. One side of the shell, is an exact copy of the other part, like a mirror image.

Protozoa: They are single celled eukaryotic animals. You can find protozoa mainly in moist soils or freshwater and in the oceans. They are the smallest of all animals. They are mainly parasites and they can reproduce even in the body of other animals. Some examples of the protozoa are amoeba, euglena and paramecium.

Arthropods: They are animals with segmented bodies and they form a large section in the animal world. Some of the Arthropods that have existed from the Precambrian era are spiders, crabs, butterflies, etc.

Annelids: They included various worms with cylindrical bodies such as earthworms, leeches, etc. You will still find these worms in your garden. I know they are all creepy and crawly, but it's amazing to know that they have been existing since the time the earth was formed!

Some of the other animals are:

• Sea pens
• Jellyfish
• Trilobites
• Cnidarians
• Yeast
• Sponges
• Corals
• Starfish
• Sea cucumbers
• Sea urchins
• Hydra
• Shells
• Snails
• Clams
• Squids
• Moss
• Stromatolites
• Girvanella
• Blue-green algae

Whew! That was amazing. Next time you see a starfish or an earthworm, won't it be amazing to know that they have been existing in this earth right from the time when the earth was born? It sure will. Now, it's the humans who rule the world, but 4600 million years ago it had been these Precambrian animals who had ruled the earth.