USING ADI TO QUANTIFY A COLOR CHANGE IN CRAYFISH

Jennifer Welborn

Do Crayfish Change Color If Their Environment Changes?

A Guided Inquiry Lab for 7th grade Life Science

• Background: There is anecdotal evidence from bass fisherman that crayfish are able to change color depending on their surroundings. A (cursory ) literature review of this phenomenon showed that no formal research has been done in this area. Students had an additional informal lesson about research funding (or lack thereof) because of this finding.

• Students designed and conducted a controlled experiment to

see the effect of changing environment color on crayfish color.

• ADI was used to quantify a color change.

Frameworks Alignment

• Science Inquiry Skills are part of the Massachusetts frameworks for Science and Technology as well as the New Generation Science Standards

Grades 6–8 Formulate a testable hypothesis. Design and conduct an experiment specifying variables to be changed, controlled, and

measured. Select appropriate tools and technology (e.g., calculators, computers, thermometers,

meter sticks, balances, graduated cylinders, and microscopes), and make quantitative observations.

Present and explain data and findings using multiple representations, including tables, graphs, mathematical and physical models, and demonstrations.

Draw conclusions based on data or evidence presented in tables or graphs, and make inferences based on patterns or trends in the data.

Communicate procedures and results using appropriate science and technology terminology.

Offer explanations of procedures, and critique and revise them.

First week of Life Science– Science as a Way of Knowing: Inquiry Unit-- student pairs make qualitative and quantitative observations

of their crayfish

Second Week– Students design and conduct a controlled experiment with crayfish and use ADI to

quantify a color change

Download ADI and click on Spatial Analysis

Click on File and Choose Open Picture

Choose None

Make sure to photographlabels so that photos can beIdentified later

Choose rectangle tool

Record the R, G, B values on a table. These are the values of the color of the crayfish after it is has been on dark rocks for 3 days and has just been transferred to light rocks.

Draw a rectangle whichlies just inside the SHARPIERectangle on the crayfish

Click on graph colors

Graph of R, G, B values of the image of the crayfishafter it had been on dark rocks for 3 days.

Click on enhance colors

Choose red vs blue normalized,But play around with the otherOptions first!

Graph of red vs blue normalized afterthe crayfish was on dark rocks.

Choose Open Picture to open the “after” picture

Record the new R, G, B values in the data table. These are the values of the color of the crayfish after it has been on light rocks for 3 days.

New graph of R, G, B values!

Red vs blue normalized image afterCrayfish has been on lighter rocks..Hmmm……….

Graph of red vs blue normalized afterCrayfish has been on lighter colored rocks