Homeopathy, a belief from 200 years ago that if you took something that mimicked the symptoms of a disease you could prevent a disease, or that extremely diluted water with a molecule of something will be curative, has never been shown to work in any clinical trial.

Nonetheless, some people swear by it, much as people believe other placebos. What to do if your doctor recommends it? In the United States, a doctor is ethically forbidden from prescribing a placebo outside a clinical trial, but it is known some do. And lots of folk medicine/alternative medicine/integrative medicine people will claim it works if you believe it works. 

In 1907,Francis Galton recorded the entries from a competition where people guessed the weight of an ox. After analyzing hundreds of estimates the statistician found that while individual guesses varied wildly, the median of the entries was surprisingly accurate, within one percent of the ox's real weight.

Galton published the results and his theory of collective intelligence, the "wisdom of crowds," became part of the lexicon.

Advocates are claiming medical marijuana can help to fight the opioid epidemic but data show the opposite. Rather than being at lower risk, people who use medical marijuana may be at higher risk for non-medical prescription drug use.
Much of medical marijuana usage was always recreational and a new study in the Journal of Addiction Medicine finds that people who use medical marijuana have higher rates of prescription drug use - including pain relievers.

Does Use of Medical Marijuana Increase or Decrease Prescription Drug Use?

Though we read a lot of claims about impending extinction, the biological reality is that we don't know anything about 99.9999999 percent of species that have ever lived. And then there are species only newly discovered that are immediately declared endangered because an academic only recently named them in a print journal.

The mix of bacteria (microbiome) of bee bread, the long-term food supply stored within a hive for young bees, is now at risk, according to a new estimate.

The scholars are blaming modern monoculture farming, commercial forestry and gardeners could be making it harder for honeybees to store food and fight off diseases, a new study suggests. Human changes to the landscape, such as large areas of monoculture grassland for livestock grazing, and coniferous forests for timber production, is affecting the diversity of the ‘microbiome’ associated with honeybees’ long-term food supply, the authors claim. 

One of the most fundamental predictions of Einstein's theory of relativity is the existence of black holes.

Although gravitational waves from binary black holes have been detected, direct evidence using electromagnetic waves hasn't happened and astronomers are searching for it with radio telescopes.  But then how can you tell them apart? Radio images have a limited resolution and image fidelity and at realistic image resolutions, even highly non-Einsteinian black holes seem like normal black holes.