You can make an estimate - one that is better than chance would produce - of how many children have been born into a Dutch or Danish family by counting the storks' nests on the roof of their house.
In statistical terminology, it would be said that a positive correlation has been found to exist between these two things.
What sounds like proof of an ancient myth is actually something far more valuable. It is an easily remembered reminder of a useful truth: an association between two factors is not proof that one has caused the other.
When you hear #NoEstimates advocates quote project failure numbers and then make the conjecture that those failures were caused by estimating, and then further conjecture that NOT Estimating would have prevented those project failures, they (the No Estimates advocates) are subject to the fallacies in Chapter 8 of How to Lie With Statistics