Evolution into a new species? Evolution takes time. Millions of years. What we are doing with our tools... rather ...what we have been dong with our tools for thousands and thousands of years ...with our tools.... has been a process to enlighten and give us a survival edge....making life more bearable ..with less time consuming work...and to lengthen our lifespan in the doing. THAT has been the reason... To make things better for the "human condition" fire... the wheel... cooking food... preserving food... growing food... the lever... the fulcrum.. the hammer , innovations of technology...... one can say that eyeglasses are an "enhancement" as much as cybernetics....it is simply a matter of degree ... any tools we use could be considered an enhancement... the computer...the smartphone....etc... So said ...it is simply a matter of incremental and unnoticeable changes we make and adopt on our progression to give us a survivable "edge" Until now that is... Now we have technology making disruptive changes due to the speed of it's immediate use. Now we can leap ahead of the curve of our own expected growth in a given time... Now we can alter things down to the molecular level and beyond. Now we can make tools (robots and nano tech ) that small. A lot is happening. But it takes millions of years for any given species to evolve even slight adaptations to their physiology ... Evolution takes time. Trial and error spanning huge amounts of time....to make sure the new adaptation works...properly. We can bypass much of the process of evolution....now.....saving us time...in trial and error.. But ...that doesn't mean it is a smart, intelligent or wise thing to do. In the end evolution is a natural process....which is dependent on environmental stresses...forcing the adaptation. With us...we can technologically instigate changes and adaptations in the human body now ...in response to a changing climate and air, water and toxin qualities... to survive ...what we are doing to the planet.... But that is hardly evolution... That is merely a stop gap measure....stealing time... Now back to the topic of "at what point does a person possibly lose their humanity if a computer AI were put in his / her head ..in place of a human brain..." Adding cybernetic parts to a human ...a hand here... a foot there....legs ...arms...whatever...does not mean they are a "cyborg" ....or less human... a person using technology to make bearable...enhance...or give an edge in survival ...has always been with us.... From the "crutch" ...to eyeglasses...to artificial limbs... They don't detract from our humanity...they help to retain our humanity. Taking out a human brain ...and putting into the skull cavity an AI that has all the experience of that individual ...and the ability to keep growing,,,remembering...learning...and forgetting (which is an important safety valve) ... Is just another method to survive, enhance, grow and keep up with the curve of technological growth... It is just another tool. like the tablet stylus...pen...pencil....chalk...stick...all the way down through history... Just another extension of our will...of our sentience... yet again ...It falls back to the same issue of who has control. and how tyrannical they are .