Sea urchin fossils in one layer of rock have longer spines than the sea urchin fossils in the rock layer directly above them. What do the differences between the two sets of sea urchin fossils suggest about them?

A.) The longer-spined sea urchins may be related to the shorter-spined sea urchins.

B.)The longer spines developed as the shorter-spined sea urchins grew older.

C.)The shorter-spined sea urchins stretched their spines to ward off predators.

D.)The shorter spines did not protect the sea urchins well enough and they died off.

Question

Sea urchin fossils in one layer of rock have longer spines than the sea urchin fossils in the rock layer directly above them. What do the differences between the two sets of sea urchin fossils suggest about them?

A.) The longer-spined sea urchins may be related to the shorter-spined sea urchins.

B.)The longer spines developed as the shorter-spined sea urchins grew older.

C.)The shorter-spined sea urchins stretched their spines to ward off predators.

D.)The shorter spines did not protect the sea urchins well enough and they died off.

koikkara · Answer

Hmm...... https://scholarspace.manoa.hawaii.edu/bitstream/handle/10125/3984/v23n4-452-466.pdf?sequence=1

anonymous · Answer

The shorter spines did not protect the sea urchins well enough and they died off.