
In reality, the image is a picture of a South African moth using "eye-spot mimicry". Check out a picture of the moth taken from a different perspective here. Surprised?
If your instinct was to try to guess what was "in" the image, you are not alone. It is a very tempting response to the question, "What do you observe?". However, as scientists, it is important that we understand the difference between what we observe, and what we infer. In this blog post, we will first learn about observations, the types of observations, and the relationship between observations and data. We will then look into inferences, and how we can use our observations in order to make scientific inferences.
Observations
In reality, an observation is any information you can gather using the five senses and scientific instruments and tools. In other words, what can we actually see, smell, taste, touch, hear, and measure in the picture? There are two sets of concentric circles, the colors of burnt red, orange, white, and varying shades of brown, and symmetrical patterns and colors.

Qualitative Observations:
| Quantitative Observations:
|
Qualitative Observation: Polar bears live on ice. This polar bear appears to be clinging on to a melting glacier. |
On the other hand, an inference is a logical conclusion based on observations and prior knowledge. "Based on my observations of the tomatoes, I can infer that the tomatoes are fresh because they are bright red, round, and shiny, and have a mass of 15.5 grams, which means that the tomatoes have a reasonably high water content." In this example inference sentence, note how I incorporated both qualitative observations, quantitative observations, and prior knowledge in the "because" portion of the sentence. Without this important "because", I would not be fully supporting my logical conclusion (inference).
Let's go back to our first picture example. I can infer that the object in the image is a winged insect using "eyespot mimicry" because of the symmetrical patterns and colors, concentric circles, and soft appearance. Again, note how the "because" portion of the inference is where I incorporated my observations and prior knowledge.
Below are example sentences to help you write your own scientific inferences:
- “I infer ___________________, because ________________________."
- “Because _________________, I infer __________________________.”
- “Based on my observations, I infer ________, because _____________.”
1. What is the difference between a qualitative and quantitative observation?
2. What is data?
3. What is an inference?
4. How are observations and inferences related to each other?
5. Write one scientific inference sentence using the two global warming pictures and observations above (qualitative and quantitative). Remember to use one of the following sentence formats:
- “I infer ___________________, because ________________________.
- “Because _________________, I infer __________________________.”
- “Based on my observations, I infer ________, because _____________.”
Homework
STUDY your all vocabulary since the beginning of the school year, and your notes on observations, inferences, and cause-and-effect relationships. Also study the information on the "Cause and Effect: Human Activity and Global Warming", the "Observations vs. Inferences", and "What is Science?" blog posts. There will be a quiz tomorrow!