Sea Sponges Are Animals, Not Plants

A sponge sits in one place and has no face, so it is easy to take it for a plant. NOAA’s National Ocean Service says otherwise. Sponges are simple aquatic animals with dense, yet porous, skeletons. They come in a wide variety of colors, shapes and sizes and are often mistaken for plants. They are also among the oldest kinds of animal. According to NOAA, certain species have a fossil record that dates back approximately 600 million years, to the earliest period of Earth’s history. There are approximately 8,550 living sponge species. Most are found in the ocean, though numerous species live in fresh water as well. They are very simple creatures with no tissues, yet they matter to their neighbors. NOAA notes that sponges filter water and collect bacteria, which can affect water quality on a coral reef.