5 By these have the isles of the nations been parted in their lands, each by his tongue, by their families, in their nations. (YLT)
This verse (also verse 20 and 31) seems to suggest that God formed the new nations by splitting the new languages by (biological) family group? Is this view correct?
The story of the Tower of Babel follows an account of the genealogy of Noah's descendants in Genesis 10. The story is an attempt to explain and tie into their knowledge of the world and its history their experiences and relationship with God, in particular:
the diversity of language the Hebrew people encountered on their travels, especially considering they are all understood to be descendants of Noah;
the discovery of advanced and unfamiliar building technologies (in ruins) in the lands around Babylon; and
instruction or guidance on how God wants the Hebrew people to live.
If God had randomly split family groups in order to form the new nations, this probably would not have been consistent with the experience of the Hebrew people, who would have noticed in their nomadic situation that nations appeared to be distinguished by geography, then within those lands by language and finally within language groups by genealogy, clan or family group.
They would have encountered a number of family groups in the same location who spoke the same language, but would have noticed that both family groups and language were geographically determined.
According to Genesis, God scattered the people into different nations but kept family groups together, dividing the languages geographically. The story of the Tower of Babel provides an explanation of why God brought about this change in situation from Noah and his three sons embarking from the ark together, to their own experience of many nations and languages.
My opinion is that this story preserved old linguistic thoughts. Probably a lot of people thought "What was the first language ever?" or "Why there are so many languages and not just one?" or even "What is the language that God uses?"
This story basically answer those basic questions: According to this story, the mother of all languages is Hebrew, and all other languages had been created by God, by "mixing" this basic language.
Modern linguistics indicates that there are two (maybe three) different "base languages" that all modern languages developed from.
Asking "what came first" does not give an accurate portrayal of reality. Many things change in many small ways simultaneously. Over time, cultures and languages of relatively isolated people drift apart until we consider them to be different. There wasn't necessarily ever a cataclysmic event that suddenly changed everything overnight.
The Tower story was likely spuriously inserted among the geneologies as a post-hoc explanation for why people speak different languages. As with other Biblical interpolations, the redaction interrupts the flow of the surrounding text. Without the story, the geneologies read seamlessly as a continuous text.
Genesis has multiple cycles of construction and destruction. During the construction phase, an action of man is declared wicked, Yahweh destroys it, and the cycle repeats.
Gen 10 concludes the Flood story with the scattering of nations and a set of geneologies. Although Biblical geneologies may appear to be about individual people, they often really describe entire nations. (Recall 1Tim 1:3-4, ... so you may tell them not to teach other doctrines, nor myths and endless geneologies...) In the context of the Flood, it appears the initial division was by ancestry, from which different languages developed.
The next (short) cycle, in Gen 11, is the building of the Tower. Apologists often claim that the builders' crime is pride or disobedience, when they say, let us build a tower into the heavens, let us make a name for ourselves, let us not be scattered across the earth (Gen 11:4). But in modern vernacular, the builders are saying, let's build and name a city (make a name for ourselves) so that we can live together (not be scattered). "Tower into the heavens" is equivalent to the modern "skyscraper". Heavens is just another way to refer to the sky. "Into the heavens" is likely just and idiom meaning really high. (Recall Gen 1:20, Let birds fly above the earth across the dome of the heavens. Many translations say, across the sky.)
The crime, in Yahweh's eyes, is cooperation because (Gen 11:6) if as one people, speaking one language, they can accomplish this, nothing would be beyond them. As with the Flood, the story ends with the scattering of nations. In this case, division in speech appears to precede the development of nations. Another set of geneologies follows.
