PHYLUM ARTHROPODA

 

It is the largest and most varied phylum in the animal kingdom, with organisms ranging from marine and freshwater based organisms, terrestrial (land-based) ecosystem, and can vary tremendously habitats, life histories, and dietary preferences. [47]

 

 

 

 

 

 

 

 

 

 

 

 

 

Main characteristics include:

Exoskeleton (external skeleton) composed primarily of chitin 

Possess bilateral symmetry

Ventral nervous system - arthropods have a paired nerve cord that runs down their bellies - ventral

Open circulatory system. Instead of a closed circulatory system of interconnected veins and capillaries, their blood is pumped through open spaces called sinuses. [47]

 

About the Hermit Crab (type of Crustacean):

 

Did you know...?

 

As a hermit crab grows, it molts, shedding its exoskeleton and creating a new, larger one. After building up enough water pressure in its body, it splits the old skin. [48]

 

A crab may eat its molted skin, possibly for its calcium, vitamins, and minerals. [48]

 

Hermit crabs do not only use their shells for protection from predators - these are also used to prevent dehydration. [48]

 

Hermit crab are omnivorous scavengers, so they basically consume whatever they can find. [48]

 

These live about ten years and mate sexually in salt water. [48]