By the statements presented, we have the situation where the trilobites are the oldest of the species, thus they will be on the bottom layer. The corals are second ones that emerged, so they will be found in the second bottom layer, and after them come the amphibians that will be found in the third layer. The dinosaurs evolved after the amphibians, so since they are younger than them, they will be located in the second layer from the top, with the birds evolving from the later dinosaurs and being the youngest, they will be found in the top layer.
