Convergent evolution is still a possibility - more than one hominid was walking around on two legs that isn't thought to be one of our direct ancestors. Traits that are advantageous can occur more than once in more than one genetic lineage. Bipedal walking could have existed for a long time before our ancestors adopted it.Lozza62 wrote:According to aboriginal lore Yowie were on the continent prior to 40/50 thousand years ago.Footprints have been found embedded in rock so I wonder how long they have been here.Whatever they are they definitely were established long before homo sapiens.To confuse to the puzzle of them more some footprints have been estimated to be millions of years old ...if that's true they were evolved bipedalism when we were still swinging from trees.
The fossil record is, and always will be, an incomplete picture. The conditions for fossilisation are specific and it's impossible to know what hasn't been recorded. It's also the case that many fossils have never been found due to things like mining, road building, etc which have destroyed them without anyone even noticing. Many more won't be found simply because nobody's looking in the right place.
I agree with you on one broad point - we don't know as much as we think we do, and natural history isn't some cut-and-dried set of theories that neatly explains everything. Some things are not explainable because we don't have the right context for them and when they don't fit some people's favourite theories, they ignore them (witness the general public's ignorance/indifference regarding the Yowie) or, even worse, denigrate or discredit any idea which is outside their 'neat and tidy' view of things.
I'm still not 100% convinced the Yowie is even necessarily a primate - it may be for all I know, but I wouldn't rule anything out. They've been here a long, long time...they may be from a group of creatures which predates humanity quite literally by ages.