I've been an avid birdwatcher for many years, and have been fortunate enough to travel to some amazingly cool places in search of avifauna. Besides exploring my own country, I've been to Canada (several times), Belize (twice), Ecuador (twice), Iceland (twice), England (twice), Scotland, Sweden, Finland, Denmark, Russia, Spain, Portugal, and Malaysia.
One place I've never been, though, is Australia, which is a shame because it's got some incredible animals. And despite a pretty well-deserved reputation for having far more than their fair share of wildlife that's actively trying to kill you, most tourists come back from trips to Australia alive and with all their limbs still attached in the right places.
The main reason for Australia's unique ecosystems is that it's been isolated for a very long time. During the breakup of Pangaea, the northern part (Laurasia, made up of what is now Europe, North America, and most of Asia) separated from the southern part (Gondwanaland, made up of what is now Africa, South America, Antarctica, Australia, and India), something on the order of 180 million years ago. The other pieces gradually pulled apart as rifting occured, but Australia remained attached to Antarctica until around thirty million years ago. At that point, the whole thing had a fairly temperate climate, but when the Tasman Gateway opened up during the Oligocene Period, it allowed the formation of the Antarctic Circumpolar Current, isolating and cooling Antarctica and resulting in the extinction of nearly all of its native species. Australia, now separate, began to drift northward, gradually warming as it went, and carrying with it a completely unique suite of animals and plants.
The reason all this comes up is a sharp-eyed Australian loyal reader of Skeptophilia, who sent me a link to a news story about a recent discovery by a dedicated amateur fossil hunter and birdwatcher, Melissa Lowery, who was looking for fossils on the Bass Coast of Victoria and stumbled upon something extraordinary -- some 125 million year old bird footprints.
At that point, the separation of Australia and Antarctica was some 65 million years in the future, the sauropod dinosaurs were still the dominant animal group, and Victoria itself was somewhere near the South Pole. Lowery's find led to a full-scale scientific investigation of the area, and uncovered a great many more bird tracks, including some with ten-centimeter-long toes. Also in the area were the footprints of dozens of kinds of non-avian dinosaurs."Most of the bird tracks and body fossils dating back to the Early Cretaceous are from the Northern Hemisphere, particularly from Asia," said Anthony Martin, of Emory University, who led the study. "Our discovery shows that there were many birds, and a variety of them, near the South Pole about 125 million years ago."