When you learned about the history of human evolution in school, there's a good chance you were shown one all-too-familiar image. That picture probably showed a conga line of human-like creatures, from a primitive ape at one end to a modern man proudly strolling into the future at the other.
For many people, this iconic image captures evolution's slow but inevitable march from the simple to the complex.
But it also raises a puzzling question: If this really is how evolution works, then why are there still monkeys and apes?
Surely, if humans evolved out of primates, there's no reason that so many species should have remained so primitive.
While it might be easy to dismiss this as a trivial question, the answer actually reveals a fascinating detail of our shared evolutionary history.
In fact, it uncovers what scientists have called a 'widespread and persistent misconception' about the nature of human evolution.
So, Daily Mail asked some of the leading experts to explain why we might need to rethink our place in the evolutionary lineup.
If evolution is real, why are there still monkeys?
One common view of evolution is that it is a linear process which takes primitive species and slowly brings them closer to perfection.
Unfortunately, this is a greatly simplified perception of how evolution really works.
Professor Ruth Mace, an expert on human evolution from University College London, told Daily Mail: 'Think of the evolutionary process as tree-like. All living species are at the tips of the branches.
'Humans and monkeys are on branches that separated at some point. Both branches still exist.'
If we were to trace those branches back in time through the generations, we would eventually find that they merge into a single species.
Modern humans' closest living relatives are chimpanzees and bonobos, with whom we share about 98.7 per cent of our DNA.
We also share a lot of common traits with our primate relatives, including anatomical features, complex social hierarchies, and problem-solving skills.
If humans evolved from primates, why are there still monkeys?
Humans didn't evolve from any of the monkey or primate species that we see today.
Although we do share a lot of DNA with some species, up to 98 per cent in some cases, that is because we have a common ancestor.
Between six and ten million years ago, a population of primates split into those that would become chimpanzees and bonobos and those that would become humans.
Humans and monkeys are just different branches of the same evolutionary tree, but there's no reason that one needed to disappear for the other to emerge.
It might be easy, therefore, to think that modern humans evolved from a group of chimpanzees or bonobos, leaving the rest of the species behind on a lower rung of the evolutionary ladder.
However, modern genetic data shows that this isn't the case.
Anthropologists currently think that humans split from the family containing bonobos and chimpanzees somewhere between six to 10 million years ago.
Scientists call the species at that branching point our 'last common ancestor'.
When scientists talk about early humans like the Neanderthals and Homo erectus, it can seem like modern humans replaced all the species that came before them.
This creates a misconception that every earlier species either evolved to be more human-like or died out.
However, since Darwin's 'tree of life' doesn't grow straight up like a beanstalk, but spreads like a bush, there are also lots of evolutionary 'dead ends'.

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