Crabsolutely Clawsome!






On our kayaking trip through an estuary, we encountered the intertidal animal, the Fiddler crab. The male crabs have an enlarged cheliped that serves no useful function other than to attract females. The larger the cheliped, the more attractive it is to the female. This physical difference between the male and the female is called sexual dimorphism. Fiddler crabs are in the phylum Arthropoda. This phylum is characterized by its jointed limbs and exoskeleton made of chitin. We were able to visualize the old exoskeletons the crabs molted in order to grow larger. Their highly developed sensory organs helped them to be aware of our presence and caused them to continuously move away from us.

Candace Hickey

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