Experts calculated how our physical appearance could change under a number of scenarios, including a 'water world' if melting ice caps cause rising sea levels.
They also considered what would happen in a second ice age which could be triggered by an asteroid strike, and if humans colonized other planets.
Dr Matthew Skinner, a paleoanthropologist at the University of Kent, examined the three scenarios and worked with artist Quentin Devine to help visualize how humans could look in the future.
Dr Skinner said some changes – such as webbed feet and hands becoming widespread – could take place very quickly as some humans already have a genetic mutation that produces webbing.
Other changes to allow humans to live in extreme conditions might only take place over hundreds of generations of natural selection, or require genetic engineering.
He said: 'We could genetically engineer ourselves if important enough to survive. Some of these things we might try to develop as a necessity rather than occurring over time naturally. Others could occur over tens of thousands of years.'To adapt to a 'water world', Dr Skinner expects humans would develop webbed hands and eyes like those of cats to help us see in the poor lighting conditions underwater.
We would also retain a layer of baby fat into adulthood as an insulator for spending long periods submerged.
Regular foraging in shallow waters could lead us to develop artificial 'gills' to help us breathe, extracting oxygen from the water and delivering it to the bloodstream.
This would also lead to our lung capacity becoming greatly reduced, and our rib cages shrinking.
An additional layer in the retina - like cat's eyes - could develop to help us see in poor light under water.
We might also evolve an extra translucent eyelid to protect the eyes from water.
In the scenario of an ice age, Dr Skinner predicts that our skin would become very pale to help us produce more vitamin D from less sunlight, we would have more body hair, and we would develop more muscular physiques.
Our noses and face size would increase to help warm inhaled cold air in the nasopharynx, the area behind the nose.
We would become stronger, as reduced resources and technologies would mean physical power becomes more important. Read more: