The first humans to arrive in Andalucia were Homo erectus about 1.4 million years ago. At the moment nobody knows how long they were in residence. Continuous occupation started about 500,000 years ago when Homo heidelbergensis arrived. He developed into the Neanderthals. About 30,000 years ago the Neanderthals were replaced by Home sapiens, hunter-gatherers. Somewhere around 6500 BC, Neolithic people migrated into Andalucia and horticulture gradually replaced hunter-gathering as a way of life. About 4500 BC the farming communities started to build megalithic structures and construct ditched enclosures. Soon after that man started to use copper and then bronze. Throughout the period, settlements became larger and more permanent, fortified settlements appeared and art developed in many ways from cave paintings to idolic plaques and sculptures. Networks of communication have always been a feature of mankind, first for mutual support and transmission of ideas, then for exchange of goods and finally for trade. It is a fascinating story but in order to understand why things happened as they did it is necessary to lay three erroneous ideas to rest.
Evolution and Home sapiens
Recent research into human DNA has shown that practice of dividing humans into species that existed between two dates, is a flawed system. We are the same species as Neanderthals and probably the same species as Homo heidelbergensis.
The Nature of Humans
Everybody has heard the phrase, 'the noble savage' and many people have been taught that hunter-gatherers were warlike, aggressive people struggling to survive in a hostile environment, jealously guarding territory and possessions. Sorry, if hunter-gatherers were such people then they would not have survived. Research since western Europeans started to explore the world, amongst surviving hunter-gatherer tribes and particularly that since the turn of the 20th century, has shown that hunter-gatherers were the most unselfish people ever to have inhabited the Earth.
Statistics are peculiar creatures and averages are misleading. You will often read that the average lifetime of man during prehistoric times was far less than that of today. An average lifetime back in prehistoric times may be 30 years. However that figure is arrived at by taking all births and deaths. Childhood mortality was very high, far higher than today, and that fact alone accounts for the low average lifetime. Many people lived into their seventies and even eighties in prehistoric times. What is more, they were far healthier than we are today.
I have expanded on these misnomers in the articles 'Evolution of Homo Sapiens' and 'Solitary, poor, nasty, brutish and short'.