Far in the distant future, the human race will look nothing like we do now. In fact humans will branch out into several different subspecies, each of them possessing a different shape or form. But to begin, let's start at the beginning of the distant future.
By the year 5 million AD, Earth was in the grip of a New Ice Age. Many humans were now spread across the universe, but most lived in self-sustaining orbital cities. These humans however were nothing like us. They had undergone several physical changes, which had allowed them to survive the tumultuous years leading up to the big freeze. These New Humans, or Numans (Homo sapiens novellus) were much taller than we are, with an average hight of 7-8 feet for both sexes. Their skin colors were much more radical, coming in shades of dark red, bright white, and even lime green. Their anatomy remained mostly unchanged, apart from their newly gained hyper-intelligence.
By the year 100 million AD the ice age had ended, and the Numans returned home to find an earth that was much warmer and tropical from pole to pole. Sea levels had risen, flooding many of the old Numan cities, forcing thousands to relocate and rebuild further inland. Unfortunately, due to decreased land mass, there were much fewer places to relocate to. The Numans found themselves arguing over where to to build and who owned what piece of land. To conserve much-needed space (and to prevent all-out war) a quarter of the Numan population downloaded their consciousness' into computers and other machines. A new Human race offshoot was born: The Digital Humans aka Digiforms (Homo sapiens numerus). The Digiforms usually represented themselves either as pixelated faces on monitor screens or as pixelated human figures projected on mobile hologram platforms. They had no physical form, existing only in cyberspace, unable to interact physically with Numans.
By 200 Million AD all seven of Earth's continents had collided, forming one massive supercontinent and one enormous global ocean. Earth's rotation had slowed considerably, resulting in 25 hour days. There were now three human offshoots populating the planet: the Numans, still unchanged, the Digiforms, and the Vaporforms (Homo sapiens nubilus), humans that had mutated into contained clouds of pure consciousness. The Vaporforms communicated telepathically and interacted through telekenesis, which made up for their lack of hands and a mouth. Softspoken, they preferred to let others talk first before offering their truly unique insight. For obvious reasons, they avoided windy areas and stayed away from devices like vacuum cleaners. Because of their vulnerability, they often traveled in floating glass spheres kept aloft by their own mind power.
Humanity's last phase of change finally occurred around the year 5 billion AD. By this time, the sun was nearing the end of its life and had swollen to three times its original size. The New Human races were forced to take drastic measures in order to survive the massive amounts of heat and radiation pouring from the dying sun. They tried bouncing the sun's rays off orbital mirrors, installing gravitic satellites around the sun to slow its expansion, and using massive umbrella-like shade stations to shield Earth from the glare. One by one, these projects failed. As these events unfolded, the New Human races were unaware that an entirely new race of human offshoots had appeared right under their noses. They were called Lumins (Homo sapiens illustro), beings of pure hard light energy each less than five inches tall. The Lumin's skin tones were fairly monochromatic like their ancient ancestors the Old Humans, but their eyes glowed with solid colors as varied as the rainbow, and then some. In addition, they all wore glowing unisex robes and headpieces to match whatever eye color they had. They were the most resilient offshoot to date: they required no food or water and the sun's heat did not affect them. They weren't immortal however, and had a limited life span. They could be killed by many things in their harsh environment, but their intelligence allowed them to prevail.
Meanwhile, things became unbearable for the other human subspecies. The oceans had dried up, and the plants had all died leaving the entire planet a bleak red desert. Only a handful of savage animals remained on earth, mutated to survive in the endless sand dunes. The Vaporforms had become extinct, evaporating under the elderly sun's intense rays. The Numans and the Digiforms, still unaware of the tiny Lumins' existence, left earth to find new places in the galaxy to live. Therefore the Lumins, the last remnants of the human race, were left to dwell in the ruins of the old human cities, making lives for themselves using decaying technology and their own intuition. By a nothing short of a miracle, the humanity had survived till the end of the world.