Some thoughts about the question 'Where would Fynbos fall on the timeline from cycads to the present?'

I shall share some thoughts that I often share with guests as I lead walks in Kirstenbosch and in the Fynbos, some from the training notes for Garden Guides, and some additional things that have come to my mind over the years.

Dinosaurs and cycads would have existed at about the same time in Earth's history

When the French arrived, they would probably have looked around and thought 'This looks like home. Let's try grapes.' I recall chatting with a scientist at Grootfontein Agricultural College and he said that when he visited Israel, he thought that it looked just like part of the Karoo or Succulent Karoo. Species composition is very different, but the structure of the plants and the landscape look very similar.

Then one day I looked at the Gondwanaland map and I realised that the Cape has not always been the SW tip of a land mass as is typical of Mediterranean climates (winter rainfall), and it may have been close to what is now the Equator as I saw suggested in the 70s, or close to where what we call the North Pole is located. I also remember seeing somewhere that the Cape has not had ice ages or other catastrophic events that have caused major extinctions, and so the diversity has been enhanced. Genetic isolation is ensured by the diversity of soils, altitude, rock, moisture availability, aspect (N, S, E, W), etc. and this has enabled many species to establish themselves effectively. So, changes from possible tropical, colder, summer rainfall, or other climates, as well as seismic activities leading to mountains and valleys being formed, sea level changes, and so much more, have all contributed to the amazing diversity that we have here.

The Gondwanaland map in the Gondwana Garden at Kirstenbosch

Levels of radioactivity would have been much higher so many half lives ago, for example if the average half life is 300 years, then 6,000 years ago the levels of radioactivity would have been about 2,000 times what they are now, and this would doubtless have contributed to genetic mutations.

The Sun is losing mass as mass is converted to solar energy, and so if all has been as we see it now, then the Earth would not have been the same distance from the Sun, if it was orbiting the same Sun that it is orbiting now. The Earth is also absorbing solar energy and converting it to mass through photosynthesis and other processes. All of these factors would have affected the gravitational pull between the Sun and the Earth, and between the Earth and the Moon. And yet, navigators have used the same constellations for navigating for thousands of years, so somehow the gas bottle is being refilled, and the celestial clock is constantly being rewound. But this does make me suggest that geological time cannot be linear, and things cannot possibly have been simply as we see them now when we go back many thousands of years, let alone 'millions' or 'billions' of years in time. So I stress that geological time is what is mentioned, not necessarily time as we know it now.

Now - regarding the age of Fynbos, I suggest that many things have added to what we now call Fynbos, and some things could date back to before the times of the dinosaurs and some things could have happened at the time close to the most recent speciation event that DNA analysis suggests was about 65,000 years ago, or possibly about 150 years ago, and every era in between. It has clearly been a continually adapting and diversifying landscape and hub of biodiversity.

I am sure that other guides will have other valuable ideas. Some information is hypothetical and some is pretty solid. But all of these contributions add to my appreciation for the amazing part of the Globe in which we are privileged to live, and that we get to share with our guests from many other amazing parts of Earth.