I read an opinion piece (on pharmacology) that said you’re not supposed to cite papers that are more than 3 years old because after that it becomes junk science. You can’t possibly be serious? Every experiment ever conducted has to be reproduced every 3 years? That would cost trillions. A lot of stuff can’t be reproduced. Thousands of species have gone extinct, so field observations can’t be reproduced. Space probes take more than 3 years often just to reach their target planet. And there are ethics boards and human rights laws that make certain human experimentation illegal today. Does that mean what we’ve learned from these experiments is automatically “junk science” because we’re either not allowed to reproduce the experiment or because the subject of the experiment no longer exists? It’s bullshit.