Please remember that all dating methods, even those termed "absolute," are subject to margins of error. That is a very small amount of possible error range. Modern studies almost always use two or more methods to confirm dating work and to build confidence in the results obtained.
The skeleton displays traits that place it firmly as the first baleen-whale relative known to emerge after an ancient group of whale ancestors called basilosaurids split into two: one branch led to the toothed whales, which include sperm whales (Physeter macrocephalus) and dolphins, and the other to baleen whales.
Researchers reported their findings on 11 May in Current Biology.
The law was first proposed in the 17th century by the Danish scientist Nicolas Steno.
Superposition in archaeology and especially in stratification use during excavation is slightly different as the processes involved in laying down archaeological strata are somewhat different from geological processes.
An example would be that the silt back-fill of an underground drain would form some time after the ground immediately above it.
Other examples of non vertical superposition would be modifications to standing structures such as the creation of new doors and windows in a wall.
Chronological sequence is all that is really required.
However, human beings love to see factual precision, and we want to know how old something is.
“There are so many changes from their terrestrial ancestors,” says Olivier Lambert, a palaeontologist at the Museum of Natural Sciences in Brussels, and lead study author.
“It’s a nice example for evolution at work.” Before now, the oldest known baleen-whale fossil was 34 million years old.
Thus, 1587 is the post quem dating of Shakespeare's play Henry V.