We have enough studies on the impacts of nutrition in the womb and the impact of experience and neglect on brain development in children that we can be sure that intelligence is more advanced. More complex languages leads to more complex thoughts. Better nutrition leads to greater intelligence. Both for our normal communication but also for languages to describe abstract ideas like mathematics.
If this still doesn't sound definite, then I think we are getting into the issue of what is intelligence and how do you measure it in a person or a population. But then we would need to get into answering just how can we be sure humans are more intelligent than a wide selection of animals and even non-animals. Same for creativity and sophistication.
We have enough studies on the impacts of nutrition in the womb and the impact of experience and neglect on brain development in children that we can be sure that intelligence is more advanced. More complex languages leads to more complex thoughts. Better nutrition leads to greater intelligence. Both for our normal communication but also for languages to describe abstract ideas like mathematics.
If this still doesn't sound definite, then I think we are getting into the issue of what is intelligence and how do you measure it in a person or a population. But then we would need to get into answering just how can we be sure humans are more intelligent than a wide selection of animals and even non-animals. Same for creativity and sophistication.