Question

how do fossils found in different geological layers provide evidence for earths changes over time?
select all true statements:
a. fossils in lower rock layers are usually older than those in layers above them.
b. similar fossils found on different continents suggest the continents were once connected.
c. fossils show that the types of plants and animals on earth have changed throughout history.
d. fossils only form in volcanic rocks, so they cannot show environmental changes.
e. extinct species found in older layers indicate that life on earth has evolved over time.

Explanation:

• Option A: Follows the law of superposition, where lower sedimentary layers (and their fossils) are older than upper layers.
• Option B: This supports continental drift theory; identical fossils on separate continents imply the landmasses were joined.
• Option C: Fossil records track the shift in plant and animal species across geological time, showing life's progression.
• Option D: Fossils primarily form in sedimentary rocks, not volcanic ones, and they do show environmental changes (e.g., marine fossils on land). This is false.
• Option E: Extinct species in older layers, paired with modern species in newer layers, demonstrates evolutionary change over time.

Answer:

A. Fossils in lower rock layers are usually older than those in layers above them.
B. Similar fossils found on different continents suggest the continents were once connected.
C. Fossils show that the types of plants and animals on Earth have changed throughout history.
E. Extinct species found in older layers indicate that life on Earth has evolved over time.