The scientific method – biology
The scientific method – biology
Lina and Michael are watering their plants, and discover something. The flowers in the window seem to do a lot better than the flower in the corner. Why is that? Do the plants enjoy the view? No, flowers don't have eyes.
It can't be the view. Is it because the plants in the window are numerous? Do they like company? No, Lina doesn't think so. But Michael believes that plants might affect each other by being closely placed together.
That's why they grow in dense forests, he thinks. Lina believes it's the light in the window that matters. But Michael sticks to his idea. So Lina and Michael have made a discovery, an observation, and stated one possible explanation each. One hypothesis each.
Now they want to move on and carry out an experiment, to answer the questions: "Does light matter for plants to grow and thrive?" And "Are potted plants better off placed next to other potted plants?" -- They plant four similar seeds in similar pots. There is a similar, and equal amount of, soil in each pot. The conditions are intended to be as identical as possible. Two of the pots are both placed in bright windows... ... and the other two in dark corners.
Michael makes sure two of the seeds get company, to test his hypothesis. Every morning Lina and Michael check the pots and note what they see. After a month they look completely different. The experiment has a result: In the bright window there is a tall and strong plant. In the darker corner, the seed set root, but the plant is small, and does not seem to be healthy. -- Now it's time to reflect on the result and make conclusions, to make an analysis.
Michael notes that the plants in a group ... have not grown quicker than the unaccompanied ones. Nothing indicates that the plants are positively affected by company. He rejects his hypothesis. Lina though, notes that her hypothesis is supported by the experiment.
It seems correct. The plants in the window, that recieved lots of light, are healthily growing. -- But Lina can't be sure. It might have been a coincidence that made the plants in the window grow better. Perhaps there are other factors that matter? Before you can make a conclusion, you have to make several experiments to get more solid data. -- What have Lina and Michael done?
They made an observation They stated one question each They stated one hypothesis each They carried out an experiment They studied the results They made an analysis to answer their questions, and considered what new questions arose. Lina and Michael have used a scientific method. There are several kinds of scientific method, and researchers use them to find answers to their questions. In physics, chemistry, social science... and Biology.
But what about Michael? His hypothesis was wrong? Was that science? Yes, a surprising result is still a result. Thorough and well performed science may well lead to hypotheses being rejected. -- This is how Biology researchers work.
Some, like Michael and Lina, study potted plants. Others learn about cancer cells by observing them under a microscope. While others catch fish in a lake to find out if the number of fish is affected by the construction of a new bridge. They all have in common that they use scientific methods. -- But hey! Let's try the light hypothesis again.
We might get a more solid result. Okay. Let's use a hundred seeds this time. And if the hypothesis is correct, we have to figure out what it is about the sun that the plants like. - Okay. I have another hypothesis about that. - What?
Lina and Michael have understood how science works. A result causes new questions, new hypotheses, and new explorations. The search for knowledge never ends