The phyla we are looking at this week say it all in their names- echinoderm means spiny skin, while arthropod (the group that crustaceans are part of) means jointed appendages. During our trip to Pat Bay we hope to find some of the member species, from barnacles to sand dollars, and learn about their adaptations and habits.
From seining to skits its been a wonderful week! I hope everyone enjoyed learning about some of the most numerous and celebrated marine inhabitants. Understanding what species are related, where they get their names and why they have certain characteristics gives us all sorts of information to share and the background to learn more about each group of animals.
ECHINODERMS are invertebrates with a hard exoskeleton and, often, sharp protrusions. They frequently have five-part symmetry like a star, and use a water vascular system for structure and circulation. Most move using tiny tube feet with suction cups. They are only found in marine environments.
CRUSTACEANS are a group of arthropods that are biramous, meaning they have branched limbs and complex larval stages. Like other arthropods, they have an exoskeleton they have to molt as they grow, and their many jointed limbs and segments have evolved to accomplish specific tasks, like claws (chelipeds) for crushing and cutting and mandibles for grabbing and eating.