A bird's feather: the result of exaptation? Image from freeimages.com

Exaptation : Extreme Language Change

In 1990, linguist Roger Lass transplanted an idea from evolutionary biology to historical linguistics: exaptation.

Exaptation is the repurposing of existing elements for brand new functions. In biology, the classic example is birds’ feathers: originally believed to have developed as heat-retaining insulation, they provided a convenient basis for flight. A lucky accident, if you will. And there are plenty of instances that fit that bill in language change.

Lass’ classic example involves the development from Proto-Indo-European to Proto-Germanic. PIE had a system of alternating vowels (called ablaut) to mark aspect in verb stems. For instance, a present stem might show -e-, while -o- signified perfect and -ø- (zero, or no vowel) was the marker for aorist. Ancient Greek actually preserved that pattern quite well, and Lass gives the examples:

  • Present: lpo (I leave)
  • Perfect: léloipa (I have left)
  • Aorist: élipon (I left)

However, Proto-Germanic did something quite odd. Instead of using it to indicate aspect, it repurposes it to show number in the preterite tense. Look at these examples from Gothic:

  • Present: beitan (to bite)
  • Preterite 1ps: bait
  • Preterite 1pp: bitum

Considering that -a- is the Germanic reflex for PIE -o-, here, we have the same alternation – -e-, -o-, -ø- – but representing something else entirely.

An Idea with Wings?

Cross-discipline metaphors rarely fit exactly like a glove, and it’s clear this isn’t quite like feathers being exapted for flight. For a start, feathers still fulfil both functions: a cosy coat as well as flying apparatus. In general, with exaptation, we’re talking about wholesale transformation of something that had ceased (or was about to cease) to be meaningful any more. Lass called this morphological ‘junk’ initially, but this has been a source of disagreement. Just what is ‘junk’ in a language?

Still, it’s a compelling metaphor, chiefly because it gets the imagination churning. How can things change so drastically in such a short time? What does language look like while it’s changing like this? Does it happen a lot? Can we see it happening now? Sometimes the best ideas are the ones that spawn more questions.

Exaptation hasn’t gained universal acceptance as a theory just yet, some three decades on from Lass’ initial paper. Some say it just boils down to reanalysis, like many similar changes. Others maintain that it’s a very particular direction of reanalysis, so it is unique and worth a place of its own in the textbooks.

Whatever its status, it does throw up some absolutely fascinating examples of extreme change.

You can access Lass’ original 1990 article at this link!

Learning Old English? Iceland could be a good detour. Picture from freeimages.com.

The Path to Old English – Taking the Long Route via Iceland

I leapt at the chance to study Old English when the opportunity arose recently. I’m focusing on language change as part of my masters programme, and here was an exciting prospect to explore this in action in my own language.

Disclaimer: I’m a complete newbie. I’ve never studied Old English before. But I was stunned to find out how much of the grammar was oddly familiar. That’s not only because present-day English is the descendant of Old English. In fact, the unexpected boost was due to the fact that I’ve spent so much time with Modern Icelandic.

So how does knowledge of a different modern language help you learn an ancient one?

Well, the Icelandic spoken today is remarkably similar to the Old Norse of a thousand years ago. Its system of inflection is the most undisturbed of all the present-day Germanic languages. Where English, Dutch, Swedish, and even relatively conservative German lost or collapsed their grammatical case endings, Icelandic preserved their intricacy almost in its entirety.

Wind back a thousand years…

Wind back a thousand years, then, and you undo centuries and centuries of change that simplified the systems of those other languages. And at that point, at the end of the 10th Century, English was still young enough to bear a huge family resemblance to its Norse cousin.

Just look at the paradigms for house in Old English and Old Norse:

Old English

Singular Plural
Nominative hūs hūs
Accusative hūs hūs
Dative hūse hūsum
Genitive hūses hūsa


Singular Plural
Nominative hús hús
Accusative hús hús
Dative húsi húsum
Genitive hús húsa

Here you see some recurring themes in these young Germanic languages. For instance, the zero ending of the plural nominative and accusative with strong neuter nouns, the -um of the dative plural and the -a of the genitive plural are all hallmarks of their shared linguistic DNA.

It doesn’t stop there. Besides noun endings, many other features are still shared by Old English and Old Norse at this point – features preserved in Modern Icelandic today. They include the difference between weak and strong adjective endings (which German also clings onto), and sibling sets of personal pronouns (including a dual number), that almost look the spitting image of each other.

Unsurprisingly, you actually don’t have to wind back too many more centuries to get to the point where this pair were the same language (perhaps another 1500 years by one reckoning).

Heavy Lifting Done!

At the simplest level, this little voyage of discovery is just a fascinating observation in its own right. It leaves you wondering just how mutually intelligible the languages still were at that point in time – could Lindisfarne monks, for example, just about make out what the Vikings were shouting at them in that strangely familiar tongue?

Beyond that, however, it also shows the incredible utility of side-stepping from one subject to another related one. So much previous experience in Icelandic can be of use when starting out in Old English. The big grammatical challenge, the heavy lifting of getting your head around case and noun inflection, is already done. Just as it is in different ways, when skipping from German to Norwegian, or from Dutch to Afrikaans, or from Icelandic to Faroese.

It’s certainly a compelling argument for building up your polyglot stash by hopping between fairly closely related languages – a much-loved technique in the community.