University tests prove conclusively that scientists are sometimes wrong. Does this mean we should disbelieve everything scientists say? Should we toss out of the window widely-attested scientific findings about such important things as the age of the earth, the health effects of tobacco or the processes of climate change? Funnily enough, no. We should believe them when they are right and disbelieve them when they are wrong . The more difficult question is: how can you tell? The answer to this is in two parts. The first is, you need to ask other scientists. Scientists themselves have two terms for this - peer review, and replication. Peer review is where you get other scientists to look at a work of science and check that the methodology is sound, the evidence has been properly gathered and supports the conclusion, and so on. Replication is what you do when results are tentative, or based on small samples - you run the experiment or test...
'Contemplating the teeming life of the shore, we have an uneasy sense of the communication of some universal truth that lies just beyond our grasp.' - Rachel Carson