At the end of the International Botanic Congress in Melbourne, Australia, in August 2011, I took a tour led by two Victoria botanists, Nigel Walsh and David Cameron, showing us plant wonders of southeastern Australia. And wonders they were.
Australia’s native plants are very different from those familiar to me in the United States. First is the Northern Hemisphere-Southern Hemisphere difference: before the age of dinosaurs, the continents, which had been a single entity (Pangea), split. The southern landmass, today South America, Africa, India, Australia and Antarctica, remained together as one continent, Gondwanaland, but separated from the northern continents, now North America, Europe and Asia, known as Laurasia. Thus, many of the plants of the continents that were Gondwanaland have been separate from those of Laurasia for 150-175 million years, fully long enough to produce vast differences. There are plant families and lineages within families that are only found in the Southern (or Northern) Hemisphere. The Southern Hemisphere plants were part of what I wanted to see.