So, let's take another look at the available evidence and see if any other possibilities present themselves.
Doesn't this fact support the notion that simple organisms evolved into more and more complex organisms over time, with the more complex organisms buried and fossilized above the earlier and simpler life forms?
Many of the layers also show a certain specialization.
Some layers contain mostly fish fossils while others contain land-dwelling creatures such as dinosaurs.
Since each of these layers seems so specialized it is easy to conclude that one type of creature gave rise to the next type of creature over the course of whatever time it took to form the various layers between them.
Radiometric dating and many other techniques are used to support the idea that this transformation process took tens and hundreds of millions of years.
This is consistent with species abundance contributing heavily to evolutionary patterns." After all, "It's very rare to find fossils of lobsters" ( Link ).
General mobility, ability to survive catastrophic conditions, and other ecological/habitat factors could also reasonably contribute to the differential location of trilobites vs. For example, coelacanth fish exist in the fossil record for what are thought to have been 400 million years.
What is especially interesting is that the fossils do appear to show a progression from the most "simple" of organisms, such as single celled creatures like bacteria, to the most "complex" organisms, such as vertebrates, mammals, and of course humans.
This evolutionary progression seems to be clearly demonstrated in that certain kinds of creatures in the upper layers are rarely if ever seen in lower layers.