"the species would have looked similar to modern rats but ranged in size from about 1.5 kilograms to five kilograms."
Yes, I noticed that — but, it’s not what was in the headline or lede. This is just a pet peeve of mine, so I probably tend to over-react. Still ...
Why are “football fields” a unit of measurement in the media; when we already have acres or hectares? (BTW, when used as a unit of measurement, does the “football field” include the end zones? Canadian football fields are about 50% bigger than American fields — how is a Canadian supposed to know which “unit” of area is being reported?) Why are larger areas said to be so many “Rhode Islands” (the comparable Canadian unit is “Prince Edward Islands”), rather than sq. miles or kilometers? Because we’re all too dumb to understand standard units of weights and measures.
At least football fields and states (or provinces) actually have standardized, fixed sizes — but, what is a “dog” as a unit of measurement? If you own a Great Dane, you would be disappointed to learn how small these ancient rats were in comparison.
I concede that these sorts of comparisons sometimes make some sense. For instance, the “Astronomical Unit” has actually become a standardized measure of great length. Of course, none of us have ever travelled between the Sun and the Earth; so we can’t exactly relate intuitively to an AU any better than “miles”, or “light minutes”.