What do scientists believe is the "first" animal to evolve? jellyfish sponge cyanobacteria Rewatch

## Step 1<br />The question is asking about the first animal that scientists believe evolved. The options provided are jellyfish, sponge, and cyanobacteria.<br />## Step 2<br />Cyanobacteria is not an animal, but a type of bacteria. Therefore, it cannot be the first animal to evolve.<br />## Step 3<br />Between jellyfish and sponge, the sponge is considered to be the first animal to evolve. This is because sponges are simple multicellular organisms that lack true tissues and organs, which are characteristics of more complex animals like jellyfish.<br />## Step 4<br />Sponges are believed to have appeared around 600 million years ago, during the Precambrian era. This makes them the earliest known animals.