Final answer:
The question of whether Neanderthals had modern language capabilities is debated; anatomical evidence suggests they may have had limitations, but genetic evidence of the FOXP2 gene implies some language capacity.
Step-by-step explanation:
Based on fossils and genetic evidence, it is debated whether Neanderthals had modern language capabilities. Philip Lieberman suggests that due to anatomical differences, mainly related to the position of the larynx and the vocal apparatus, Neanderthals might not have been able to produce the full range of human speech sounds. However, the existence of the FOXP2 gene, associated with language ability, in Neanderthals indicates they could have had some capacity for complex language.
Complex language likely gave Homo sapiens a significant advantage over Neanderthals by facilitating coordination, efficiency in group activities, and the transfer of knowledge across generations. Though Neanderthals exhibited some anatomical limitations, DNA evidence shows they mated with modern humans, suggesting a closer relationship and possibly shared attributes between the two species.