Question

Which statement about Tilman and colleagues' studies of the diatoms Synedra and Asterionella is true?

1) The species that reached the highest stable population when grown alone drove the other species to extinction.
2) The species that reduced silica levels the furthest when grown alone drove the other species to extinction.
3) Both species were able to coexist when grown together.
4) The species that went extinct varied at random in different trials; sometimes it was Synedra, sometimes it was Asterionella.

Answer 1

The studies show that the diatom species able to most reduce silica levels when grown alone drove the other to extinction due to competitive resource depletion.

Step-by-step explanation:

The statement about Tilman and colleagues' studies of the diatoms Synedra and Asterionella that is true is: the species that reduced silica levels the furthest when grown alone drove the other species to extinction. This phenomenon occurs because diatoms compete with other phytoplankton for silica, which is a critical resource for their growth. In these studies, the predominant species manipulated the availability of silica to the extent that its competitor could not survive.