Parkland Series by Victor Kelleher

Cassie has always been told that humans cannot survive outside Parkland, the huge fortress enclosure where humans and other apes are guarded by the mysterious keepers. But Cassie is sure that there must be life beyond the walls when she catches a glimpse of a "wild" boy.

The Earth of our distant future has become a strange and frightening place. Now, thousands of years later, two off-worlder humans Anna and Joe, are sent back to this wild and unpopulated planet to try to begin human life all over again. And together with their babbling computer companions Og, Trog and Walter, they set off on a journey of hope.But what they discover is a world far more confusing, far more powerful, than they'd ever imagined... moreThe Earth of our distant future has become a strange and frightening place. Now, thousands of years later, two off-worlder humans Anna and Joe, are sent back to this wild and unpopulated planet to try to begin human life all over again. And together with their babbling computer companions Og, Trog and Walter, they set off on a journey of hope.But what they discover is a world far more confusing, far more powerful, than they'd ever imagined. Rats that seem to reason for themselves? Creatures that communicate in ancient human codes? What is going on?Following the highly acclaimed Parkland, Earthsong is the second book in a loosely linked trilogy about humanity, responsibility and freedom. Here Victor Kelleher takes those familiar themes and gives us new ways of looking at them, new consequences to grapple with. And the real truth about humankind - its ambitions, its responsibilities, its dreadful mistakes - is here for all to see. less

This is the third novel in the loosely linked trilogy whose first two titles are "Parkland" and "Earthsong". Two teenagers from the 21st century travel back to neanderthal times and become marooned.