The Be Verb

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Johnson｜Fossil Hunting; Language can be seen as a record of the past. Economist, July 21, 2018
("Much of the gunk and irregularity of language begins to make sense when approached as a kind of fossil hunt. Why does the commonest verb in English -- 'to be' -- have the wildly irregular conjugation am-is-are-was-were? Nobody would design such a verb, and indeed no one did. It is in fact a mash-up of three proto-Germanic roots, one [es-] of which produced [present tense] am-is-are, one [wes-] of which yielded was-were (replacing the past tense of the am-is group, in a process called suppletion), and one [beu-] resulting in be itself [as well as being and been]. It is the duckbilled platypus of verbs, an old hybrid of features. But just as evolutionary biology explains the platypus, historical linguistics shows how the three verbs piled up on each other")

Note:
(a) Dave Wilton, Be. Wordorigins.org, Oct 25, 2007
www.wordorigins.org/index.php/more/1014/
("Our modern verb to be is actually a conflation of three distinct roots: es-, wes-, and beu-. The modern inflections of to be are a jumble of inflections of these three original roots. And this conflation has been going on for well over 1,200 years.  By the time we reach the Old English period, the es- and wes- forms had already combined into a single verb, wesan. * * * By the beginning of the 13th century, the conflation of beon and wes[a]n was complete and our modern inflections had come into being. * * *  (Source: Oxford English Dictionary, 2nd Edition)" )

The above is a summary from OED. One may read the Web page "be, v" in
http://www.oed.com/
, and click the sectional heading "Etymology."  I suspect you may use a library computer to read www.oed.com (I am in a public library).
(b) As far as I can tell, biologists have not tried to explain platypus, in terms of evolution, biology or otherwise. At least one reason is biologists are not using platypus to do experiments. It is safe to say that platypus is little understood.
(c) There is no need to read the rest, which is inane.