As the previous chapter showed, Jespersen re-cast language change as an accumulation of individual speakers’ judgments. But Jespersen himself never showed the substance of that “human practice” — who actually moved, where, and how. In 2007, the archaeologist David W. Anthony fills that gap.

Not an invasion, but a franchise

Anthony doesn’t depict the spread of Proto-Indo-European’s speakers as a large-scale military conquest.

As I suggested in chapter 14, the initial spread of Proto-Indo-European dialects probably was more like a franchising operation than an invasion. (Article 136)

A handful of steppe chiefs relocating to new territories, drawing local populations in through institutions — patron-client relationships, guest-host customs — this is the actual picture Anthony paints of the dispersal. There is no trace here of Schleicher’s vision of language “growing like an oak tree.” What’s there instead is the real social action of people who left no names, no records, but were unmistakably real.

Schleicher, 1861 Language grows like an oak tree language as a natural object Anthony, 2007 Dispersal through chiefs' migration and institutions language as human history Across 146 years, the pendulum swung far, from natural object to human history
From Schleicher's natural object to Anthony's human history. Diagram: ToL

Horse teeth, and the word for wheel

The evidence Anthony used to support this claim was also of a different kind from anything else in this genealogy. He examined the wear a bit leaves on a horse’s teeth to date the origin of riding (overview article). He checked the mere existence of the mother tongue’s words for “wheel” and “axle” against the archaeological date of the wheel’s invention (roughly 4000–3500 BCE), to establish a lower bound on when the mother tongue was spoken. This is, in its own way, the furthest-reaching application of the method of “regular correspondence” that Rask established in Chapter 1 — except what’s being compared is no longer grammatical endings, but a horse’s bones and the history of a tool’s invention.

Independent confirmation, from ancient DNA

In 2015, Anthony’s steppe-origin theory was confirmed independently by an entirely different science — the technology of sequencing DNA directly from ancient human bone. It emerged that, roughly 4,500 years ago, about three-quarters of the genetic ancestry of people in Europe suddenly shifted to ancestry traceable to the people of the Pontic-Caspian steppe. To the question “is language change a natural law, or a human practice?” the hard-to-dispute evidence of DNA preserved in bone brought an answer.

At the end of the genealogy

And so we’ve traced six chapters. The question Jones opened became a method in Rask’s hands, a table in Grimm’s, gained a metaphor in Bopp’s, was fixed as a natural object in Müller’s and Schleicher’s, held both natural law and human force together inside Brugmann, was set free as human practice in Jespersen’s, and finally, in Anthony’s hands, came down to earth as a history grounded in real archaeological evidence.

ChapterFigureIn a phrasePosition
1Jones → RaskAn intuition that it’s no accident becomes a testable methodThe question is born
2Grimm, BoppA correspondence table and an organism metaphor — neither yet literalLeans natural law
3Müller, SchleicherLinguistics is a natural science. Language lives but has no historyNatural law
4BrugmannAn exceptionless sound law, yet analogy is a human force tooNatural law → human
5JespersenSimplification isn’t decay — it’s progress, driven by humansHuman practice
6AnthonyThe spread of language is itself the migration and institutions of nameless peopleHuman practice

In a nutshell — the question of why language changes has no final answer yet. But the sheer fact that this pendulum kept swinging for 221 years teaches something in itself. The pull to fix language as a “natural object,” and the pull to reclaim it as “human history,” are probably both, from the very start, written into the nature of language itself.