There are creatures in this world that would never fail to amaze us. One of them is Sand Dollars. For sure you have seen a sea urchin. But if you are from New Zealand or Africa, there is no doubt that you are already familiar with the sand dollars, a type of sea urchins that others have never seen before.
Sand urchins are also called “snapper biscuits”, “sand cakes”, and “sea cookies” in New Zealand and “pansy shells” in Africa. They are flat and burrow in the sand. And yes, they are sea urchins. But if you have never seen one, for sure you will not think of it as a sea urchin when you by one from a gift shop or when you find one on the beach.
These sand dollars are cousins of the starfish. They are hard when they die and they can be found on any beach from all over the world. But many of them can be found in New Zealand and Africa. The sand urchins live at the bottom of the oceans. They have thousands of hair-like tentacles that let them burrow in the sand as their defense mechanism. They hide from predators like the large pink sea stars, snails, ocean pouts, sheep heads, and other types of fish that would prey on them.
According to MNN, sand dollars are carnivores. They are using their spines and cilia to move the food particles through the sand and into their mouth. Usually, they eat microscopic bits of algae but there are times that it can also be tiny fragments of other animals. This is why they are considered carnivores. On its underside and center of their body is where you can find their mouth which is also called the “Aristotle’s lantern.” It has tiny-sharp teeth like parts that are arranged in five sections. This way, they can grind up food particles.
The sand dollars propel themselves using their five sets of pores. These pores move seawater and gas in and out of their bodies in order to move. Young sand dollars would swallow sand to increase their weight. That means they need sand to survive the strong currents. When the water is still, these creatures stand on one end and they burrow the other end in the sand. And when the water gets rough, they would lie flat or burrow their sand to hold their ground.
The sand dollars can live up to 6 to 10 years in the wild. Usually, they would gather in large groups and can cover ten square feet of the ocean floor that would have up to 625 sand dollars.
If you have browsed the internet for sand dollars, you will notice that live and dead sand dollars look different. They would differ in color as well as the detail that you can see on the bottom of the creature.
If you find live sand dollars, they would have a dark purple to almost-black color. The dead ones, on the other hand, will have a lighter color. Sometimes, they would look almost white or beige. If you happen to be on the beach and you find a live sand dollar, please throw them back into the water. These creatures are very important for the ocean’s ecosystem.