Evidence
The Mayans and Aztecs had chocolate, pirates have their booty, and scientists have evidence. Evidence is what scientists live, breathe, observe, and experiment for. How is evidence more important than chocolate or treasure? In the race to determine which scientist has the right explanation for some fancy phenomenon, the one with the most evidence wins. Only the prize here isn't some trophy, it's knowledge. We'd take that over a trophy any day.
Evidence is something we'll see pop up in all of the different parts of the scientific process. The evidence ball gets rolling when a scientist makes an observation. Evidence from that observation will guide them in making a hypothesis and will give the hypothesis context. For example, if a scientist is studying why birds fly south in the winter, they probably need to have some evidence that birds actually fly south in the winter so the other scientists don't put them on the Don't Believe 'Em List.
When the time to experiment comes around, collecting evidence is a super important process. How and what evidence is gathered can make or break an experiment. The experiment has to be well designed, so that the evidence will actually answer the experimental question. No, we can't just feed rats espressos for fun.
The scientist also has to actually know what they're doing when they collect the evidence, too. Not knowing how to use a mechanical pipette or measure in centimeters can result in all kinds of error that turn glorious evidence into garbage. Scientists also have to watch out for the dreaded random errors that can give some funky data, as well as their own silly mistakes. No, 2 + 2 does not equal 7.
One evidence-strengthening strategy scientists like to use is repetition. They do their experiment over and over and over and…you get the picture. This may seem tedious, but it sure gives them a lot of evidence. For example, let's say someone bet us $1 million that they could make a basketball shot from half court. What if we had seen them do it, just once? We probably wouldn't take that bet. However, what if we had seen them do it once, but had also seen them miss one hundred other times? Given this amount of evidence, we're willing to bet our collection of Star Wars Pez dispensers that that ball isn't making it through the hoop.
Same thing goes for scientific evidence. If scientists see a result was only produced once, they're definitely giving it the side eye. But if they see a result was produced a thousand times, now they're all up in its business.
Every major scientific theory is also backed by ridiculous amounts of evidence. This evidence may come from different scientists in different fields of study, but it all points toward the same conclusions.
The moral of the story is that evidence is everywhere and it's super important to scientists. If we're collecting evidence, we must remember to be careful to avoid errors and try to be as accurate as we can. If we're reviewing someone else's experiment, we have to look for that evidence and treat it like gold. Or chocolate.