These are: In each of these cases it is not possible to prove that the assumptions are true.
For example flooding can greatly alter sedimentation rates, and with clocks over 5,000 years old, the original conditions cannot be known with certainty.
Ernest Rutherford is the father of nuclear chemistry and nuclear physics.
He discovered and named the atomic nucleus, the proton, the alpha particle, and the beta particle.
Ernest was the fourth of the 12 children his parents brought up in New Zealand, and he was blessed with both high intelligence and a talent for sports, particularly rugby football.
A number of scientifically untenable - but enormously entertaining - novels have been published, exploring just this possibility.
The giant Mega-Tooth Shark (Carcharocles megalodon) is reconstructed here as a scaled-up White Shark (Carcharodon carcharias) and in 'hot pursuit' of Allodesmus, an early sea lion-like pinniped.
We will probably never know for sure why Megalodon became extinct.
But we can probably be grateful that it did: a 52-foot (16-metre) version of the White Shark with jaws large enough to engulf a rhino would almost certainly make recreational swimming or pleasure boating a LOT less enjoyable.