Almost all cacti are native to the Americas, but there is a small, relatively uncommon group of plants closely related to cacti native to tropical western Africa. How can we explain this given the information in this chapter?

Question

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The presence of a closely related group of plants in tropical western Africa suggests that the continent of Africa and the Americas were once connected, allowing for the exchange of plant species. This is supported by evidence from plate tectonics and geological studies. Option A (plants floating across the Atlantic) is unlikely due to the long distances involved and the low probability of survival during such a journey. Option B (divergent evolution) does not explain the shared ancestry between the African and American plants.

Almost All Cacti Are Native to the Americas, but There