Scientific Observation

Measurements are always taken when scientists make observations. Some measurements are quantitative - objective measurements using numbers, such as time, mass, volume, etc. Other measurements are much more subjective, involving opinions but no numbers. These are known as qualitative measurements. Examples of qualitative measurements are change in color or appearance, diet, and species interaction.

A researcher kept an egg of a little known animal in a temperature-controlled environment. The researcher observed the animal when it hatched and recorded the following data over the first ten weeks of its growth.

Week   Length (cm)   Mass (grams)   Color   Activity
1   6   10   brown   inactive
2   7   12   brown   moves slowly
3   9   15   brown   moves slowly
4   12   20   tan   moderately active
5   17   35   tan   moderately active
6   19   40   green   very active
7   20   43   green   very active
8   21   45   green   very active
9   21   45   green   very active
10   21   45   green   very active

Graph the quantitative data from the table and answer the following questions:

  1. Which of these is a qualitative characteristic of the animal observed?
    O   a. color
    O   b. mass
    O   c. length
    O   d. none of these
  2. Which of these hypotheses about the animal's change in color is most likely to be correct?
    O   a. the animal's scales dry out as it grows older
    O   b. the change in food as it grows
    O   c. in the wild, the young animals live in a different habitat than the adult animals
    O   d. the animal's skin stretches as it grows older
  3. If a mature animal is observed in the wild,
    O   a. it should be over 20 cm in length
    O   b. it should have a mass over 50 grams
    O   c. it will be brown
    O   d. it will have six legs

 

Use the grid below for your graph. There are 29 squares on the horizontal axis and 23 squares on the vertical axis. Be sure to label the independent and dependent variables with the proper units and put a title on the graph.