Complex sentence: A study from Leeds University and published in "Molecular Biology and Evolution", examiningmitochondrial DNA lineages, suggested that humans had been occupying the islands of Southeast Asia for a longer period than previously believed.
Split into simpler sentences: A study from Leeds University and published in "Molecular Biology and Evolution". Examination of mitochondrial DNA lineages shows that human have been evolving within Islands of Southeast Asia for a longer period than previously believed.