This question has already been answered -- on the radio and the pop charts. In their 1969 hit "In the Year 2525 (Exordium and Terminus)," the rock duo Zager & Evans sing, "In the year 5555, your arms are hangin' limp at your side. Your legs got nothing to do; some machine's doing that for you." This is 1010 years, they explain, after your eyes and teeth have been rendered useless by pills filled with nutrients and information. While Zager & Evans were just making scary futuristic folk-rock, some scientists believe they may not have been too far off the mark. Futurists such as Raymond Kurzweil, author of "The Singularity Is Near: When Humans Transcend Biology," believe we are headed toward an era dominated by unbelievably powerful computers and the people who join their consciousness with those machines [source: Singularity].

For University of Reading cybernetics professor Kevin Warwick, author of "I, Cyborg," the future is now. A cyborg (short for "cybernetic organism") is part human, part machine. Warwick has had a silicon chip with a 100-electrode array implanted in his arm, allowing him to control an electric wheelchair and an artificial hand with neural impulses [source: Harrell]. Irish-Spanish artist Neil Harbisson also claims to be the first true cyborg. He wears a device called an "eyeborg" that allows him to counteract his colorblindness by "hearing" various shades and hues. The eyeborg is a small camera mounted on Harbisson's head, connected to a microprocessor that converts 360 colors into different frequencies of sound [source: Hadden]. Given developments like these, it seems likely that humans will incorporate more and more external technology into their bodies over time.

Remaining completely inside the biological realm, however, geneticists have determined that within the past 5,000 to 10,000 years, the evolution of our species has sped up by a factor of 100. According to University of Wisconsin professor of anthropology John Hawks, humans in 8,000 B.C. were more like Neanderthals than like us [source: Shute]. Largely through improved nutrition, average human height in industrialized nations has increased by 4 inches (10 centimeters) since the mid-1800s [source: Dougherty]. Oliver Curry, a London School of Economics evolutionary theorist, believes this trend will continue and peak in about the year 3000 [source: Firth]. According to Curry, human height will average out between 6 and 7 feet around this time, and skin tones will trend toward a single, homogenized color. Then, he predicts, many of us will then devolve into childlike physical forms over the next 10,000 years, as global society relies more and more on medical technology instead of natural hardiness and physical exertion. Thus, the couch potatoes among us may be more highly evolved than we thought!