Interesting site, and good effort, I congratulate you on this work.
My name is Ahmed, and I am very interested in ancient history, although am a computer scientist by education and profession :). I am a British Iraqi, and your tree of the Alphabet was certainly amusing to read :), and unfortunately completely inaccurate. Below is a little background information for your reference:
According to Jared Diamond in his book, Guns, Germs, and Steel, The two indisputably independent inventions of writing were achieved by the Sumerians of Mesopotamia somewhat before 3000 BC and by Mexican Indians somewhat before 600 BC; Egyptian writing of 3000 BC and Chinese writing (by 1300 BC) may also have arisen independently. Probably all other peoples who have developed writing since then have borrowed, adapted, or at least been inspired by existing systems.
Professor Denise Schmandt-Besserat in her book, Before Writing - Vol. 1, states, It is now generally agreed that writing was invented in Mesopotamia, present-day Iraq, in the late fourth millennium BC and spread from there to Egypt, Elam and the Indus Valley. The origin of Chinese and Mesoamerican writing is still enigmatic. This leaves Sumer as the undisputed source of the first written records of any type.
In addition, Sumerian has been one of the ancient languages most studied because Sumer, an ancient civilization flourishing at the dawn of history, was located between the Tigris and Euphrates rivers in southern Iraq, where the Biblical site of the Garden of Eden is reputed to have been located.
We know little about the Sumerian people. Because the names of the rivers, Euphrates and Tigris are not Sumerian words, we can be fairly certain Sumerians were rather recent arrivals to Land Between the Rivers at the time recorded history starts, a little before 3000 BC. The earliest written Sumerian inscriptions were found on tablets in excavations at Uruk (the Biblical city of Erech) and date to around 3100 BC. Although the Sumerian language dropped out of daily use about 2000 BC, it remained a classical language (much like todays Latin) and continued to be used in classical documents until 1 AD.
Unfortunately for the Sumerians, but fortunate for us, many of their cities were burned when destroyed, baking and preserving many thousands of their inscribed clay tablets.
This, then, is a history of the origin of the written word, which starts in the foothills of the Zagros Mountains, to the north and east of that part of the Fertile Crescent we now call Iraq.
Now back to your alphabet essay. You state that "Ancient Phoenicians invented alphabet (by about 1200 B.C)". Unfortunately, this is inaccurate, since all written ancient Iraqi Languages had alphabets: ancient Sumerian had 550 letters, inscribed by means of a stylus on a clay tablet, old-form Babylonian alphabet consisted of 60 letters, much like the Sexadecimal (base-60) numbering system they invented, newer form Babylonian, sometimes known as Tiamat Babylonian, contained 24-letters. This was decreed law by Hammurabi, removing the first 36-letters of the old alphabet to preclude the names of the Angry Sons of Tiamat (they were 37 incidentally) from ever being pronounced. Later Chaldaic, Asyric and other languages were again letter-based, and had more or less the same number of letters.
Lately, sponsors of the Pharoic movement in Egypt promoted the idea that writing started in ancient Egypt, around 2900 B.C. This has been strongly refuted, and proven wrong by recent (1990s and 2000s) discoveries of written tablets in both the North and South of Iraq, dating well before 4000 B.C. The exact dates remain a mystery, since even those written "alphabetic" forms seem to have stemmed from somewhere. The British Museum, the British Library and the remains of the Iraqi National museum have excellent examples of this.
I hope the information here proves useful, and wish you the very best of luck.
Ahmed Naji (Ph.D., M.BCS, MIEE)
©Nikolai Shokhirev, 2001-2009