Consider The Crab

Park Sites: Emerson Point, Robinson Preserve, Riverview Pointe
Grade Level: Kindergarten, 1st , 2nd and 3rd Grades
Subject: Science, Language Arts
Duration: 35 Minutes
Materials: Pre-caught fiddler crabs in cage, small containers with lids

Florida Sunshine State Standards: SC.A.1.1, SC.D.1.2, SC.D.2.1, SC.F.1.1, SC.F.1.2, SC.F.1.3, SC.F.1.4, SC.F.2.1, SC.F.2.2, SC.G.1.2, SC.G.1.4, SC.G.2.1, SC.G.2.2, LA.C.1.1, LA.C.1.3, LA.C.3.2, LA.C.3.3

Overview: In this inquiry-based activity, students are told a story about “Why the Crab Has No Head”. Observations are made with live crabs and potentially the group may collect their own crabs for observation and release.

Objectives: Students will understand that crabs are wildlife and wildlife comes in a variety of forms – small to large. Students will understand that this place is home to wildlife, including crabs. Students will learn about crab anatomy and animal adaptations. Students are responsible for their actions affecting this wildlife.

Background: Fiddler crabs are invertebrates. Male fiddler crabs have one claw that is much larger than the other claw. The female’s claws are equal in size. If a male fiddler crab loses his large claw, his remaining claw gets bigger. A new, smaller claw then grows to replace the lost one. The big claw is used for attracting a female fiddler. Small claws are used to pick up food (the female has an advantage here, she has two small claws and the male only has one). Crabs breathe through gills, have eyes on long stalks and move sideways. Fiddlers live in burrows that may go down more than three feet. Hundreds travel together in groups called herds. Fiddler crabs are active by day and eat mainly bacteria, minute algae and rotting marsh plants filtered from the sand. The sand that remains after feeding is left on the ground in the form of small sandballs.

Suggested Procedure:
1. Tell (or read) the story “Why the Crab Has No Head” an African tale of the Bakongo people of Zaire, re-told for Florida.
2. After the story is told, share the live crabs with the students (in small groups).
3. Give each group a crab in a small container and encourage them to handle carefully while asking the following questions:
Legs: How many?
Alike or different?
Notice where they attach to the body.
Claws: How many?
Is one large? (male Fiddler)
Notice where they attach to the body.
Eyes: How many?
How do they attach to the body? (stalks)
Where do they attach to the body?
(the crab has no head!)
Mouth: Can you find it?
Does it have lips?
Describe the mouth parts.
Motion: Describe it (scuttle)
What direction? (sideways)
Place it on ground or bench and watch it. (observe)
Does it seem to get tired? Why do you think so?
Noise: Does the crab make noise?
How? (mouth or other body parts?)
Color: Is your crab the same color all over?
Are the colors, shapes, and sizes the same on both sides (symmetrical)?
What is attractive about your crab?
Is it clean?
Habitat: Where does the crab live?
Do they live here year-round?
Conclusions:
Did you think there were so many interesting things about crabs?
Do you think other marine creatures might be as interesting?
What other things might you like to learn about?

*** By studying the fiddler crab, you have done what some scientists do.
Observation
Scientists study something very carefully to learn more about it. ***

 

Why the Crab Has No Head

An African tale of the Bakongo people of Zaire, re-written for Florida

• It was Nzambi Mpungu who made the earth and the sky.
• And after that, my children, she made the Brown Duck and the Alligator, the Turtle and the Deer, the Panther and the Anole Lizard.
• And still she was not finished.
• She took one whole day to make the Manatee, and that was big work!
• “I will call this little one Crab” she decided, shaping a tough shell for the body and each many-jointed leg. She made two pincer claws and not two, not four, but eight legs!
• Ai, but she was tired by the time she finished the last leg!
• “Little Crab” she said to the new creature, “I will finish you tomorrow. Come back in the morning and I will give you a fine head.” And Nzambi Mpungu went to lie down on her sleeping mat.
• Crab was so excited! “Tomorrow! A fine head!” he whispered to himself. “It took Nzambi only one day to make Manatee, but it takes her two days to make me.”
• Which was not exactly true, my children. You can see that, and I can see that, but little Crab was too proud to see truth that day.
• He told each animal he met to come and see him get his head the next morning.
• “Wild Boar! Black Bear! Come tomorrow morning to the house of Nzambi and see the fine head she will give me. She is taking all night to prepare it.”
• Which is not exactly true, my children. You can see that, and I can see that, but Crab was too proud to see truth that day.
• “Gopher Tortoise! Wood Stork! Come tomorrow morning to the house of Nzambi and see the fine head she will give me. No doubt I will have a mane like Lion’s, antlers like Deer, and surely a long, graceful neck like Great Blue Heron. How grand I’m going to look!”
• He scurried away importantly, walking almost sideways with pride.
• The next morning at sunrise, there was a great crowd at the house of Nzambi Mpungu.
• The whole Scrub Jay family was there, because they are always very curious.
• The Laughing Gulls came ready to laugh at Crab, no matter how grand he was going to look.
• Lion came because he had heard that Crab dared to compare his new head to Lion’s own magnificent head.
• Vulture showed up in case there might be food.
• All these animals made so much noise, scuffling and stamping and snorting that Nzambi soon woke up and came outside.
• “Ai! Why are you all here?” She asked when she saw the crowd.
• “Crab invited us!” squeaked the youngest Armadillo, who was quite thrilled by the whole occasion. “Where is the marvelous head you have made for him?”
• “And where is Crab?” rumbled Nzambi in return.
• “Make way, make way!” cried Crab as he scuttled through the legs of the other animals, still feeling so important he could scarcely walk straight. “I have come for my fine head, Nzambi.”
• But Nzambi Mpungu looked down sternly at Crab. This little creature was not even completed yet, and already he thought he was more important that all the others in the whole brand-new world.
• She frowned and folded her strong arms. Then she slowly shook her head.
• “No Crab,” said Nzambi at last. “I think you are fine just the way you are.”
• Now that was perfectly true, my children. And Nzambi went back to her hut to think about what color she would make the Spoonbill that day.
• So Crab never did get a head. To this day, whenever he wants to see, he has to poke his eyes out from his body.
• And he still walks sideways, only now it is from embarrassment instead of pride.