I think you are making the mistake of assuming that the phonetics would be one if not the most important feature. The article points out: "Here we investigate how deeply the roots go and how the system, its cosmology and language are intertwined with our own:".

The symbolism is important and the table presented in TFA is amazing at that.

> I think it's also interesting that they are using mother and father, considering that those words have commonalities in sound across large swathes of human language.

The t/d in * m?t- is more significant than that, whereas the p in pt is less significant across world wide languages.

I'm just missing a node to Proto-Afro-Asiatic.

> Unless the author is also ready to argue Egyptian influence on Chinese, evidence should extend to other words.

Please compare Punic [zayin] (Phoenician letter 工 = S - weapon) and Chinese [工] ("gon" etc., whence mandarin 工具 - tool). Obviously both are related to metal tools, perhaps a spade stuck in the ground symbolizing mining for ore, craft, and metal tools all in one sign, and in a different interpretation the outflow of molten metal from a primitive furnace. Once you have horses, trade is a matter of weeks or months. Metal working spread slowly, and with it the words. I don't know if asia discovered smelting independently, though, I'm just hypothesizing.

The difference is that "mother" is a much older idea and the m- in principle a reference to the sound of suckling.

[zayin]: https://en.wikipedia.org/wiki/Phoenician_alphabet

[工]: https://en.wiktionary.org/wiki/%E5%B7%A5.

PS:

> EDIT: Every dictionary I can find lists father as it, which alone would need explanation

Well, it is rather close to pt (stone), which in turn is close to Pth as in the name of the god. So there is an element of veneration (stone old anyone?) that isn't present in good ol' papa (just as some languages use different personal pronouns in different registers of speech). This link is strong as pater is still used in a religious sense. or comparing as/at: turkic "ata" (father) and "at" (horse, perhaps also venerated), which is the metaphorical head (cf. capital, cattle, aleph as god and head of the alphabet, A being a top-side-down bull head symbol). I Norse as "As" is a god again (whence "asgard"). As is also a singular unit in Latin for either a single dot on a dice (whence poker ace; we also still speak of faces of a die), or prominently as the nomination of roman pennies, which incidentally have the head of a god on its observe side which is hence colloquially called heads. Oh and isn't head somewhat rhyming with "it"? Egyptian [hr] seems to exhibits the same dualism, even if the different etymologies aren't clear (xal is mentioned, but not ħər - chief, free, noble [2]). The language as a whole over time is highly self modifying, and the result is like gene code really really tightly compressed from a really small seed expanding with exponential growth. There's certainly more to this, computational methods are gaining ground with time but archeology is a game against the time. There's a baseline to human language in most of it's dimensions. So while I don't know if the concept of parenthood was fundamental to evolution (I mean I guess so, but in what time frame), but one thing is clear if modern apes reveal any clue, the first phoneme was a skreek: "Ah Ah Ahh" (or "it it it" or something) -- cf. <https://esolangs.org/wiki/Ook!

[hr]: https://en.wiktionary.org/wiki/%E1%B8%A5r#Egyptian
[2]: https://en.wiktionary.org/wiki/Reconstruction:Proto-Afro-Asi...

PPS: At that I find funny how Morse-code, as in mono-phonetic strictly rhythm based speech, is comparable to language, and how by extension of the concept, many concepts rely on ordering and a representation in numbers. So I'm curious how important maths skills were to the development of language. Basically, human speech uses a highly variable non linear numeral system to code messages. The idea of an assembly language as intermediate to spoken language reminds me of Chomsky's universal grammar. The foundations of logic must be "univalent" simply because the brain structure has to adhere to it, geometrically, combinatorially, categorically, etc. p. p. Basically https://en.wikipedia.org/wiki/Greenspun's_tenth_rule