ABSTRACT
Ice has had a major role in shaping the greening of our Earth; this is because it has greatly influenced the geographical distribution of plant and algal diversity. Geological and archeological records show that past plant extinctions occurred as part of natural evolutionary processes, especially during episodes of glaciation (“ice ages”) or as part of natural periods of long-term climatic change. One of the coldest places on Earth, Antarctica, has a limited flora, whereas the tropical regions, not having experienced the limiting onslaughts of frequent and episodic ice ages, are “hot spots” of megadiversity.
