I'd like to ask a similar question from Math.SE for the natural sciences (physics, chemistry, biology and allied disciplines).
What are examples of scientific results that were discovered surprisingly late in history? For instance, a paper where all the technology has been available for years, and the theoretical underpinnings necessary are not recent, so in principle the same research could have been conceived and published years ago.
I am particularly interested in actual publications in peer-reviewed journals.
By way of example, I think Gibson assembly would be a good one: It is a simple modification of the standard PCR technique invented in the 70s. I imagine by the end of the 80s polymerases and buffers had been developed to the point that they could handle a simple Gibson assembly, and sequencing to confirm integrity of the product (or alternatively screening a library of products until a correct one is found) would also have been feasible. Whether the scientific community at large would have been more or less receptive to this idea at the time is another matter -- and something I specifically want to disregard for this question (ie. being "late" means late in terms of only technology and theory, not politics, funding and similar non-scientific prerequisites of scientific research).