Braindroppings

Anatomically modern humans have existed for more that 100,000 years. Is it reasonable to assume that they all spoke the same language that long ago? There are certainly some universal concepts that all languages must share. For example, there are male and female humans and animals (I will neglect the occasional hermaphrodite). All humans, regardless of the era in which they live, were and are familiar with the existance of the Sun, the Moon, and Stars. I am sure that there are many examples like this. However, much of a language is based on humans interacting with their environments. An equatorial human would often have no concept of snow or winter (there are exceptions where high mountains exist). An Eskimo may have never seen rain. Language is a tool by which humans enhance their survival prospects by interacting with each other to the benefit of all the members of a group. The modern purpose of language may not be quite the same as that of a group of hunter gatherers, however, it is still all about people living and working together. Even conquered peoples often retain some degree of their former languages. For example, dialects of Mayan and Incan languages are still spoken in Central and South America hundreds of years after the Spanish conquered these lands. Surely, Indo-European conquerers did not completely wipe out the words that were spoken by non-Indo-European cultures. So, I don't really see the Darwinian concept of survival of the fittist as applicable to languages in a general sense.