There are different causes to error in measurement, most common are instrument precision and misreading the measurements. Some cases are from the experimenter judging to what they want rather than the reading itself.(no offense)
But... measurements are never accurate anyway, they're all estimations.
Here's a couple of slogans that I have found
I believe the answer is descriptive science
Descriptive research aim to produce a data that describe a condition. It doesn't trying to analyze the data and find correlation or causation. In this case, the scientist trying to make catalog of new species. The result should be a list that could describe the species of the species. There is no hypothesis or variable in this research.
Plants on Earth provide food, some even provide shelter to some animals, and plants such as trees provide oxygen to the environment.