Humanity may split into two sub-species in 100,000 years' time as predicted by HG Wells, an expert has said.
Evolutionary theorist Oliver Curry of the London School of Economics expects a genetic upper class and a dim-witted underclass to emerge.
The human race would peak in the year 3000, he said - before a decline due to dependence on technology.
People would become choosier about their sexual partners, causing humanity to divide into sub-species, he added.
The descendants of the genetic upper class would be tall, slim, healthy, attractive, intelligent, and creative and a far cry from the "underclass" humans who would have evolved into dim-witted, ugly, squat goblin-like creatures.
Race 'ironed out'
But in the nearer future, humans will evolve in 1,000 years into giants between 6ft and 7ft tall, he predicts, while life-spans will have extended to 120 years, Dr Curry claims.
Physical appearance, driven by indicators of health, youth and fertility, will improve, he says, while men will exhibit symmetrical facial features, look athletic, and have squarer jaws, deeper voices and bigger penises.
Women, on the other hand, will develop lighter, smooth, hairless skin, large clear eyes, pert breasts, glossy hair, and even features, he adds. Racial differences will be ironed out by interbreeding, producing a uniform race of coffee-coloured people.
However, Dr Curry warns, in 10,000 years time humans may have paid a genetic price for relying on technology.
Spoiled by gadgets designed to meet their every need, they could come to resemble domesticated animals.
Social skills, such as communicating and interacting with others, could be lost, along with emotions such as love, sympathy, trust and respect. People would become less able to care for others, or perform in teams.
Physically, they would start to appear more juvenile. Chins would recede, as a result of having to chew less on processed food.
There could also be health problems caused by reliance on medicine, resulting in weak immune systems. Preventing deaths would also help to preserve the genetic defects that cause cancer.
Further into the future, sexual selection - being choosy about one's partner - was likely to create more and more genetic inequality, said Dr Curry.
The logical outcome would be two sub-species, "gracile" and "robust" humans similar to the Eloi and Morlocks foretold by HG Wells in his 1895 novel The Time Machine.
"While science and technology have the potential to create an ideal habitat for humanity over the next millennium, there is a possibility of a monumental genetic hangover over the subsequent millennia due to an over-reliance on technology reducing our natural capacity to resist disease, or our evolved ability to get along with each other, said Dr Curry.
He carried out the report for men's satellite TV channel Bravo.