Is this significant? A comment at http://joannenova.com.au/2016/01/great-barrier-reef-an-icon-that-half-of… … comment at 7.28am on January 30th. He said the Great Barrier Reef is 500,000 years old, we are informed, but it hasn't always looked as it does today. Reefs on Australia's continental shelf system have taken on many forms during that time depending on sea levels – which implies they have changed on multiple occasions. The current formation of the reef is only 6000 to 8000 years old. According to the Australian Institute of Marine Science and other scientific research the current reef began to form during the Late Glacial Maximum – when sea levels were much lower and large areas of the continental shelf were dry land. Again, sea levels changed around 8000 years ago and the current reef really seems to have come into existence after that, growing upwards to cope with the rise. There is nothing surprising in that as this was also the time Sunda Land was submerged and Indonesia was separated from SE Asia and all that was left of the old land mass was islands such as Borneo, Sumatra, and Java. I have added to the comment but the basics of what the post at Joanne's place was saying was that all the doom-sayings about the end of the reef is just hype and nonsense and the reef is full of life and will continue to be until the next major see-saw movement in sea levels. What is self evident is that the reef could perhaps be taken as proof of a shift in the axis of rotation not only at 8000 years ago but at the end of the LGM. One to keep in the back of the mind.