Purple Shore Crabs

A.k.a The Purple Shore Crab

Natural History

Prediction: If Crabs prefer a habitat of sand in their natural environment, then they will spend the most time on the sand portion of our experimental setup.

Experiment 2: What Foods does the Purple Shore Crab Prefer.

Hypothesis: Purple Shore Crabs prefer to eat algae over other foods when out of their natural environment

Independent Variable: types of food given

Dependent Variable: Purple Shore Crab food preference

Zipcode zoo.com. http://zipcodezoo.com/Animals/H/Hemigrapsus_nudus/ . Feb 7. 2013

Google Images. http://ftp.dfw.state.or.us/MRP/shellfish/crab/images/Hemigrapsus_nudus_ID_ODFW.jpg . Feb 7. 2013

Earthlife. Net. http://www.earthlife.net/inverts/arthropoda.html 400. Feb 8. 2013

Keepers Web. http://www.keepersweb.org/Shorekeepers/Animals/index.htm Feb. 8 2013

Nelson Biology Text

REFERENCES

Tuna

Prediction: If Purple Shore Crabs prefer algae

in their natural environment, then they will prefer algae over other foods outside their nautral environment

Algae

Shrimp

Setup

Sources of Error

?

The Purple Shore Crab did prefer algae if they consumed any amount of food. However, the majority of the crabs did not eat so our hypothesis requires further testing.

Conclusion

Crab 3

Crab 2

Table 2: Shore Crab's food preference during a 3 minute trial.

Crab 1

None

Shrimp

Raw Fish

Tuna

Algae

Food Type

Raw Fish

Taxonomy

• Phylum: Arthropoda
• Class: Malacostra
• Order: Decapoda
• Family: Varunidae
• Genus:
• Species:

Hemigrapsus

H. Nudus

Natural History and Taxonomy

Feeding

Distribution

Predators

Habitat

http://www.bing.com/images/search?q=purple+shore+crab&view=detail&id=F3DEAB40AB5640615AD534B8F4632E51F8BA380A&first=1&FORM=IDFRIR

Lab Crab!

The lifestyle of

Hemigrapsus nudus

Yuzi Yang

Shirui Tang

Adrianne Hajdasz

Lauren Bannister

By renowned scientists

http://farm2.staticflickr.com/1182/975293286_e52dd1c1e4_z.jpg?zz=1

Exoskeleton

Bilaterally Symmetrical

Coelomate

h

Cephalisation

Body Anatomy

http://us.123rf.com/400wm/400/400/virinka/virinka1203/virinka120300096/12823373-cute-cartoon-crab.jpg

Protostome

Tagmosis

Ecdysozoa

THE END

Experiment 1: What Substrates Do Purple Shore Crabs Prefer to Live on??

2nd

Trial

Crab 3

1st

Trial

2nd

Trial

Crab 2

1st

Trial

Table 1: The Substrates Purple Shore Crabs

Most Prefer

2nd

Trial

Crab 1

1st

Trial

Small Rocks

Sand

Large Rock

Substrate

Control

Independent Variable: Different Substrates

Dependent Variable: Crab habitat preference

Our Setup

Hypothesis: Purple Shore Crabs Prefer Habitats of Sand.

Sources Of Error

Our Hypothesis was not supported.

Purple shore Crabs seemed to prefer to spend most of their time on our large rock.

Conclusion