Question

2 attempts allowed
1/29/2026
details
do now phenomenon: a discovery in the
canyon
while hiking through a canyon, a group of scientists noticed layers of rock stacked on
top of each other. in the bottom layer, they found fossils of a small sea creature.
higher up, they discovered fossils of a plant, and in the top layer, they found fossils of
a large land animal.
the scientists wondered how these organisms could all be found in the same canyon—
but in different rock layers.
do now questions:

1. which organism do you think lived first? why?
2. which organism lived most recently? why?

Explanation:

Sub - Question 1

In geology and paleontology, the principle of superposition states that in undisturbed rock layers, the oldest layers are at the bottom and younger layers are on top. The small sea creature's fossils are in the bottom layer, so it likely lived first as the bottom layer was formed earlier.

Using the principle of superposition, the top layer of rock is the youngest as it was formed last. The large land animal's fossils are in the top layer, so it lived most recently as the top layer was formed more recently.

Answer:

The small sea creature lived first. Because in undisturbed rock layers, the bottom layer is the oldest, and the small sea creature's fossils are in the bottom layer.

Sub - Question 2