|W. Kevin Vicklund
Joined: Oct. 2005
(1) Elimination by competition. Your concept of less-evolved is inaccurate - "primitive" tribes should be just as evolved as we are. They may have evolved slightly differently, but not enough to be reproductively isolated in the elapsed time since divergence. The fact that they are so similar is strong indication that the core aspects of what make us human had fully evolved before they split off.
(2) No. The features are in fact quite different.
(3) The non-biological differences arise from two genetic traits basically unique to humans - the ability to efficiently move without using our arms and the capacity for extensive abstract thought. Yes. There is one ape (at least) that has learned to sign. Yes. Some, but not extensive. Yes, but very primitive.
(4) That's a question for society at large to answer.
(5) No, and this is a violation of Godwin's Law. Just because there are natural trends, does not mean that it is imperative that we follow those trends - part of our evolutionary advantage is the ability to change the environment and the selective pressures, and another part is our concept of ethics and morals. No - again, you are entirely incorrect in your concept of evolution. Every individual in a generation is just as evolved as the rest of its generation. We are in fact less evolved than most apes, since they have a shorter generation period, and significantly less evolved than bacteria, speaking strictly from a evolutionary standpoint. Evolutionary theory does not provide any support for the arguments you try to make. These are issues for society, not science, to resolve.