Redi Redo (Katie Robinson)

Research Question and Hypothesis

Do flies come from meat?

If I leave meat in an open air jar, then flies (in the form of maggots) will come from the meat within a few days.

Standards

DCI

Life Science

HS-LS4-1. Communicate scientific information that common ancestry and biological evolution are supported by multiple lines of empirical evidence. [Clarification Statement: Emphasis is on a conceptual understanding of the role each line of evidence has relating to common ancestry and biological evolution. Examples of evidence could include similarities in DNA sequences, anatomical structures, and order of appearance of structures in embryological development.]

MS-LS4-3. Analyze displays of pictorial data to compare patterns of similarities in the embryological development across multiple species to identify relationships not evident in the fully formed anatomy. [Clarification Statement: Emphasis is on inferring general patterns of relatedness among embryos of different organisms by comparing the macroscopic appearance of diagrams or pictures.] [Assessment Boundary: Assessment of comparisons is limited to gross appearance of anatomical structures in embryological development.]

SEP

Planning and Carrying Out Investigation

Analyzing and Interpreting Data

CCC

Cause and Effect

Experimental Design

Setting up an observation over a length of time that disproves the notion that life originates in non-living objects. (cell theory)

For many years, people had the misguided belief that flies came from meat. They had no way of knowing that when they on surfaces that they can also deposit eggs that develop into larvae and maggots and eventually into mature flies. They did not always see that the flies had landed on the meat in the first place. Therefore, a doctor named Francesco Redi designed this simple experiment to find out the true origins of flies.

Independent variable

Exposure to the air (Sealed, open, covered with cheesecloth)

Dependent variables

Number of maggots present.

Series

Observe the number of maggots on the different jar situations over a period of 7* days.

*(7 to 10 days is ideal)

Constants and Controls

Jars are equal size and style

Meat is from the same package

Placed in the same location

Materials

3 jars with lids (mason jars work great!)

Cube Meat (obtained from local market)

Cheesecloth

Procedures

1. Clean all jars. Be sure they are dry.

2. Place 1 to 2 pieces of raw meat into each jar.

3. a) Jar A - Meat with Lid

b) Jar B - Meat with no Lid

c) Jar C - Meat with Cheesecloth cover*

* NOTE: squeeze meat into the cheesecloth before placing jar. This allows for the smell of the meat to be on the cheesecloth without actually coming in contact once in the jar.

4. Place outside for up to 10 days.

5. Observe daily or every other day.

6. Record observations.