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Some words used casually have different meanings than when used scientifically.
I’m going to give you an example.
When I was younger, I noticed that sometimes after it rained, I’d find earthworms in
And I’d wonder---why are these earthworms coming out of the soil where they are safe
and risking their very lives in these puddles?!
I mean, I was pretty sure they didn’t like being in the puddles; they were getting stuck
in them for some reason.
Keep in mind this was before the age of googling information, and I came up with all kinds
Maybe the earthworms actually were crazy about water, but they didn’t know how bad it was
out there until they found themselves stuck in a puddle.
Maybe when it rained, the water flooded their underground tunnels, but it somehow confused
or disoriented them so instead of digging down they dug up, launching themselves into
Either way, it was my job to rescue them, because hey, earthworms are pretty cool.
Something I can add to my resume.
My ideas about why earthworms ventured out when it rained were not really correct.
If anything, maybe one of these ideas could have been used to develop a hypothesis, which
I could have decided to test.
A hypothesis can be defined as a suggested explanation that I could then test.
But, see, back when I was a young kid, I would have told you that these were my own personal
And that’s the problem with this word “theory.”
The word “theory” tends to be casually used in this way in everyday life all the
time; I’m sure you’ve heard your friend say before, “I have a theory about that…”
When using the word “theory” in everyday life, “theory” might be an opinion, hunch,
You might say you have a theory about why there is a water stain on a ceiling or why
sushi is amazing but it’s important to understand that you are using the word “theory” very
See, a scientific theory is a very different thing.
A scientific theory is an explanation supported by scientific evidence.
It’s fortified by facts.
It’s been tested, repeatedly.
And if you want a more detailed definition of a scientific theory, we have a link in
our video details to recommend.
The thing is, a scientific theory cannot be dismissed as “just a theory.”
In order to reach the level of scientific theory, a scientific theory must be backed
by science facts and evidence supporting it, with repeated testing.
There are many theories in science.
There’s a theory of the atom- atomic theory.
There’s the theory of general relativity.
There’s the cell theory that we frequently talk about in many of our videos.
Now while scientific theories can be disproven or modified, it is important to understand
that the word “theory” in science has such a different meaning than the casual use
of the word “theory.”
When I was younger, I used to think that theories one day could graduate into laws.
I think my misconception had something to do with me learning how a bill becomes a law
and somehow I thought scientific theories followed a similar path.
I’m really not sure where I got this misconception.
But in case you have it too, scientific theories do not graduate into scientific laws.
Because they’re completely different things.
One is not more powerful than the other either; the word “law” might sound more fancy
but it’s not---they truly are just different things.
But they are both very important in science.
Scientific laws tend to describe a natural phenomena; whereas a scientific theory can
provide a scientific explanation for it.
Many scientific laws are even represented mathematically.
For example, Newton’s second law of motion shows how acceleration is related to the force
and mass of the object.
It can be written mathematically here.
But as a law, it tends to describe…not explain why.
Since we tend to specialize more with biology, let’s not forget about Mendel’s laws.
He’s often called the father of genetics: he has three laws that you can explore: law
of the segregation of genes, law of independent assortment, and the law of dominance.
These laws describe phenomena happening with his pea plant experiments.
And while these laws each describe a natural phenomena, they don’t give an explanation
of why the phenomena happens.
As a side note, that actually would have been really hard to do as DNA wasn’t yet understood
in his time.
Understanding how the casual use of the word “theory” differs from the scientific use
of the word “theory”…as well as understanding how theories and laws are different things…are
all really important in science.
Sometimes I wish science had a different word from “theory” just because the casual
everyday use of that word is so different from the scientific use of that word.
And before we go…in case you also have had been curious this whole time about why earthworms
may come out when it rains and may find themselves in puddles…check out some further reading
suggestions that mention different researcher hypotheses in the video description.
It’s pretty fascinating.
Well, that’s it for the Amoeba Sisters, and we remind you to stay curious.