Here, we see the sons of Shem discussed. There are several things worthy to note here.
God mentions these people last, even though they wind up being the ones who see God's chosen people come out of them; indeed, even the one from whom His people come is listed third. There are many lasts which shall be first and firsts which shall be last, Jesus reminds us. There is no importance to things like birth order to God, since He looks upon the heart.
"Wait," some might say, "wasn't it important to the Jewish people?" Only in two ways which are not connected to the way God sees us. The first is because the culture developed that way. We have seen before how we must follow God's Word and not the ways of man. Down through history, all the way back to Biblical times, we see the traditions of fallen man leading people away from God. Seeing oneself as important just because of birth or something that person has done leads easily to false pride, and God resists the proud and gives grace to the humble. The second reason is connected to the first, and is the reason the first developed. The promised Messiah was supposed to come any time, and nobody knew exactly how or when. So, the first boy born was automatically seen as very important.
However, remember that King David of Israel, a man after God's own heart - the man who God promised that his seed would reign forever through the Messiah someday - was the last born in his family.
Speaking of lasts, one other interesting point - usually these genealogies only mention the people from among the firstborn, but here the last is mentioned. Birth order and other reasons God might have had for naming certain ones have both been discussed previously. However, one particular name stands out to me, at least, though it may escape the notice of some.
Uz is named - the land of Uz is where Job came from. We don't know if Uz named this area himself or if his descendants did. If his descendants did it's not necessarily wrong as long as one doesn't go overboard; America has a state and Federal District named after its first president, for instance, adn the man wanted nothing named after himself in his own lifetime. George Washington was a very humble man. And, Americans don't bow down to him or anything. A similar president with much named after him after his death - Abraham Lincoln - became known for freeing the slaves. Yet, according to one biography of him, after Richmond was captured near the end of the Civil War, President Lincoln toured the area and a former slave bowed down to him. Lincoln very quickly corrected him, "Never bow down to a man, it is not proper." And, the man then stood.
Job is considered by some accoutns the first book of the Bible to be written. It's possible Job lived at the time of Abraham, though that of Jacob may be a little more likely, siply based ont he life span of Job.
Well, if this land of Uz is named after this grandson of Shem, and people multiplied in thos early days after the Flood at about the same rate as before(notice that life spans go down, but people are still living several hundred years at first, meaning they could hve dozens of children), then it is possible that a large number of people could have inhabited that area. It would have been several hundred years after the Flood, after all.
The world was about to change drastically, however - even more so than it had changed from before the Flood.