Apparently They Do So From Their Eyes, That's Nasty Right?!
The structural deference between them is that Sea urchins are more globular whereas sand dollars are flattened. Unlike sea urchins, the sand dollars burrow themselves when threatened. Sand dollars have anus opening at their back side whereas the sea urchins have it at the top.
sea stars, sea urchins, sand dollars, and sea cucumbers.
Yes they are. They are flattened burrowing sea urchins.
No - sea urchins are part of the echinoderm phylum, with sand dollars, starfish and sea cucumbers.
Star fishes and sea urchins are similar to sand dollars.
No. They are invertebrates related to starfish and sea urchins.
Sea urchins and sand dollars.
Echinoderms include sea stars, sand dollars, sea cucumbers, sea urchins, etc.
They both or found in the ocean
Echinoderma are a phylum of "spiky skin" sea life, such as starfish, sea urchins, and sand dollars.
Seastars, sea urchins, and sea cucumbers are all members of the phylum Echinodermata. Other members of this phylum include: sand dollars, brittle stars, basket stars, feather stars, sea lilies, and heart urchins.
Sand Dollars are the carcasses of dead sea urchins, and when alive, they eat though a mouth.