Sorry for the polyphyleticism here but I was thinking that parental care seperates in common sense birds from reptiles from mammals generally and that somewhere back in sometime the reptiles might differentiate mentally in us humans EASIER than it is to seperate, in any thought, birds and herps (looking lower down yet again) & whatever it is that BIBLICAL KINDS are to the be the evos thorn of, I doubt that it will be as wide a trap or net that is being discussed in this thread.
The solution I would bank on, is the topology of egg chemicals relative to traced anatomy. I have never tried to give as much thought between "birds" and "mammals" as I have between "reptiles" and "amphibians". In a innocent view it IS easier to see birds with reptiles than mammals but my consideration was not this niave.
You are correct that I would have to explain something of the *chemistry" of keratin to justify what I said. The last time I worked on THAT was with the difference of alpha and beta keratin but herpetologists were not biting. Instead, they always look rather to warm-bloodedness than take in the population constraints that might indicate how to think mammals with reptiles rather than birds. I think birds are moving to the SUN, but hey that is just me. Mammals never took off and herps simply "crawled", Biblically speaking...
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