These are from Richard Leakey and Jonathan Marks, in order of quote. They do not attempt to give any kind of scientific answer to the questions posed by the work they denigrate, and such is the case for the debunkers as well on their websites. Richard Dawkins has written a whole book on the basis of debunking of alternative theory of human origins, picking on the weakest arguments(creationisms) in his opinion, and basically lumping it all together into the famous 'Bushistic' statement, "If you're not with us, you're with the enemy"(because there's only two sides, as he sees it). To Dawkins, alternative views are not worthy of consideration, even from reputable scientists.
I'll tell you something I believe, though: the establishment is running out of gas in this effort, and more and more scientists are not listening to this cacophany of name-calling and shrill invective, preferring to let the science lead them to discovery, rather than thinking they already know it all.
What is behind the debunking fury? Perhaps these establishment icons fear this:" To have modern human beings........appearing a great deal earlier, in fact at a time when even simple primates did not exist as possible ancestors, would be devastating not only to the accepted pattern. It would be devastating to the whole theory of evolution."- W.W. Howells, Physical Anthropologist. The quoted statements above are taken from "Forbidden Archaeology".
The simple fact is that the discipline won't live by its own maxim to modify its theories when new evidence becomes available. Instead, it seeks to undermine by coming out with statements like "extraordinary claims require extraordinary evidence", thus setting up the establishment, which is challenged, as the arbiter of what is acceptable evidence. It's like what happens in 'whistle-blower' cases. The deck is stacked. Luckily, there's still free speech and the cyber-world we live in makes the acquisition and evaluation of information available to many more than previously has been the case. The very popularization of science has led many with differing perspectives on scientific problems to investigate for themselves, whether the alternative viewpoints have merit.
Thomas Jefferson called for "the diffusion of knowledge among the people. No other sure foundation can be devised for the preservation of freedom and happiness."
The National Academy of Sciences 1998 booklet comments on the teaching of science: "this process of public scrutiny is an essential part of science. It works to eliminate personal bias and subjectivity because others must be able to determine whether a proposed explanation is consistant with available evidence." It does not say the truth resides in the opinions of the most highly placed and visible academics in the field.
Finally, Titus, I hope you and many others can see that the explanation for who we are and how we got here hasn't been answered by anybody, definitively, yet, and we are doing ourselves and those who follow after us a disservice if we ignore or dismiss alternative views on the basis of thinking we've already "got it right". Cheers, Rick