I've though about the probably relationship between Gwr script and Kash-- certainly the Kash borrowed a lot from Gwr culture, and writing could well be one thing. Stay tuned.

As to regularity of development-- the Devanagari character for "a" (as well as our own Phoenician-Greco "A") is said to have developed from some Semitic version as seen in Hebrew "aleph" (which in turn is said to represent the head of an ox). And I suppose it's possible that that in turn developed from some Egyptian hieroglyph, but I'm not so sure about that

The various native systems seen in Indonesia are all said to have developed from Indic models, but later versions (I gather) than Devanagari. For ex., Batak and Bugis/Makassar script are clearly related. OTOH Javanese script looks more like one of the South Indian scripts (same for Burmese, not so sure about Thai....) But India (around 0 CE) must have had lots of scripts roiling around....

Just speculatin'.......

On Saturday, March 22, 2014 12:08 PM, Alex Fink <[log in to unmask]> wrote:
Around these parts we've all seen linguistic reconstruction problems: here are two or more modern languages; what was their common ancestor?  But I'd not before seen one at the level of graphemics, which is why I was excited to see Danny present us with one:

On Wed, 19 Mar 2014 08:42:48 -0400, Daniel Bowman <[log in to unmask]> wrote:

>2014-03-17 14:49 GMT-04:00 Alex Fink <[log in to unmask]>:
>> Ah, I was hoping you'd post that!  There is a nice reconstruction problem
>> here, if you don't mind my stating it.  [...]
>> Many of the characters in the two scripts look similar enough that one
>> wants to see them as conworld-internally deriving from a common ancestor.
>>  How might one reconstruct this ancestor?
>I've put clearer versions online:

So I sat down and tried to figure out some kind of proto-script (which he's given me his blessings in doing), and came up with this:

This is strictly a dilettante's effort, in a few major ways.  The first is that, as earlier, I have no idea what the principles of regularity in script evolution actually are.  I've tried to extract some regular principles in the developments I was positing, sometimes at the expense of locally simpler solutions (for instance the easiest way to relate the two <k>s is with left-right reflection, but why would there have been one isolated left-right reflection?[1]).  But have I actually tried to employ too much regularity, or implausible rules, or...?
The second is that I haven't been able to resist my own conlangerly creative impulses of making up little stories about what was happening in the background, changes in proto-sound values and whatever else, which go out on limbs more than is justified.  

[1] There are non-isolated instances of left-right reflection in early north Mediterranean alphabets, but I had thought this was due to the use of boustrophedon.  

So, comments, criticisms, alternative reconstructions?

Or, for that matter, does anyone have any descriptions to share of the diachronic development of their own conscripts?