Complex sentence: Rivera Pérez, 2013, p.73 The first inhabitants have been analysed with the help of Quaternary geology and pollen and give ages of 12,500 to 11,000 years BP when the paleoclimate was less cold and more humid than today.
Split into simpler sentences: Rivera Pérez, 2013, p.73 The first inhabitants have been analysed with the help of the tools of Quaternary geology, as well as using pollen analysis, and give ages of 12,500 to 11,000 years BP. At that time, the paleoclimate was less cold and more humid than today.