Thursday, March 24, 2016

Crabs

CRABS - In general, you can tell the difference between boy crabs and girl crabs by looking at the shape of the plate on the abdomen. Boys have a thinner more pointy plate, girls have a wider more rounded plate because it is used to hold the egg mass. The mothers carry the eggs because not many predators will mess with them to get to the eggs.
  • Blue Crabs are found in the Chesapeake Bay. They are very agressive, like to pinch, but are good to eat. They have a pointy-ended shell and swim fins. (you can kind of see the swim fins on the last leg of the crabs on the right)
  • Spider Crabs have a rounder body shape, often a bumpy shell that will grow algae for camouflage, and longer more spindly legs. Spider Crabs include snow crabs and king crabs like the ones seen on Deadliest Catch. A decorator crab is a kind of spider crab that attaches stuff to its bumpy shell to blend in.
  • Fiddler Crab males have one claw that is a lot bigger than the other. This is for impressing the ladies, and used to show dominance over other males. 
  • Hermit Crabs have a weak exoskeleton and thus protect it with a stolen mollusc shell. They have adapted to this lifestyle and have modified back legs that hook on the inside to hold the shell on and one claw that is slightly larger to use as an operculum.
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Computer Lab Etiquette

You are in the computer lab to do work for this class. If you are not doing work, then we will have problems.

Do not pack up early. Work until the bell or until MsJ says.

SAVE OFTEN. And if you save to a key, also save it to your number. If you lose it, you will have to do it again.

If MsJ asks for your attention, stop what you are doing and listen to what she has to say.

You may watch videos about your organism through reliable websites.

You may listen to music through the computer if you have your own headphones. Rule1 MsJ cannot hear it. You get one warning. Rule2 Turn it on and listen – no million clicks and constant changing. Take both ear phones out when MsJ is talking.