Dear Jaderis,
I found your question Quit interesting.
I would like to point out, however, that the chronologies in the Bible are not ‘Just’ for "establish descendency" of their King’s. Among other things, they are there to show accuracy in Biblical Prophecy.
For example, you look at what the OT says about the Messiah’s lineage and then compare it to anyone claiming to be the Messiah.
I would also like to point out that the Bible rarely puts things in chronological order. However, when it dos, it is clear that it is a chronological account. (For instance the Seven Days of Creation are defiantly in chronological order)
One last thing, I would like to point out that even though these chronologies are in chronological order they would not carry every son of every father. (Example: If John had Sam and Sam has Tom; if Sam had no importance to the chronology {was unimportant as far as the history of his people, or did not accomplish anything of mention} then his name would be dropped and the chronology would simply read ‘John the father of Tom’)