“The advent of brain-machine interfaces may force humans to redefine where our humanity lies; it will blur the boundary between human and machine,” says Dr Arthur Saniotis of the University of Adelaide.

Saniotis is one of the authors of e-book The Dynamic Human, to be launched today, which suggests that humans are continuing to evolve at pace, driven heavily by our interaction with digital, body-altering technologies.

He said the boundary between humans and machines had been “blurred for a long time”.

“Since 2002, about 59,000 people have received some form of neurological prosthetics, such as to help them hear or see, and this technology will develop rapidly in the coming years,” he said.

“Millions of people are currently wearing technological devices aimed at enhancing our lives: from eye glasses, to hearing aids, pace makers, bionic ears, heart valves and artificial limbs.

“We are becoming increasingly dependent on such devices and it can become easy to think of the body as a kind of machine with parts that need replacing.

“Of course, the body is not a machine but an evolutionary organism of enormous complexity.”

Co-author Professor Maciej Henneberg told InDaily human brains have shrunk, in line with human muscles, over the past 30,000 years, and our increasing reliance on technology to do our heavy lifting will continue to make our brains smaller, but their thinking function more sophisticated.

As humans have made lesser use of our physical bodies with more sedentary lifestyles, our brains have shrunk proportionately, he said.

“Brain size is mostly [about] controlling the body,” he said.

“Thinking is a bi-product of controlling the human body.”

He said because of recent innovations involving brain-machinery interaction, including high-functioning artificial limbs, it was likely this interaction would only increase.

He said our brains would continue to shrink, but our sensory organs would continue to be enhanced, as well our thinking capability overall, though advances in body-machine technology.

“Human brains will continue to shrink as we integrate [more with technology],” Henneberg said.

“Our ability to perceive and understand the world will increase [and] our memory will be better.”

Soon, humans may be able to increase our memory using digital memory storage, he said.

“It’s thinkable and possible to use those (digital) memories directly,” he told InDaily.

“If we can process this information better then we’ll be able to make better decisions with our life.”

Henneberg said he disagreed with British scientist Stephen Hawking’s warnings about the dangers of artificial intelligence, and suggested increasing mechanisation was a path humans should embrace.

“We simply need to … use them [technological advances] to our advantage rather than complaining about them.”

Other foreseeable changes in human evolution include racial characteristics becoming less distinct, while individuals become more variable.

He said recent evolutionary changes in human body structure included the expansion of metabolic disease and obesity, and changes to the number of arteries some humans have connected to their liver.