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Language Lineage

Comparing sound laws

Every sound law recorded here, from 18 families with no proven relationship to each other, lined up by kind and placed on one clock. Languages that have never been in contact keep making the same kinds of change: consonants lost at the ends of words, stops moving in chains, contrasts merging.

All families

On one timeline

AlgonquianAustroasiaticAustronesianBantuDravidianGermanicJaponicKoreanicKra-DaiMayanNa-DenePama-NyunganQuechuanSemiticSino-TibetanTurkicUralicUto-Aztecan
Hover or tab to a ring to read the sound law. Dates are rough midpoints. The text dates on each branch page are the record.

Parallel changes

By kind of change

Kinds with examples in more than one family are marked parallel. The similarity is one of kind, not of ancestry. No relationship between these families has been proven (see the Indo-Uralic and Nostratic debates).

Consonant shifts

Parallel · 11 families

Whole series of consonants move to a new manner or place, often in a chain where one change makes room for the next.

Algonquian

Austronesian

Bantu

  • Bantu spirantisation

    Eastern Bantu · c. 1st millennium BCE

    *p *t *k → fricatives or affricates / _ *i *u (*-kúpa → mfupa 'bone')

Dravidian

  • *k becomes x

    North Dravidian · c. 1st millennium BCE

    *k → x / _ non-front V (*kaṇ → Kurukh xann, Brahui xan)

Germanic

  • Grimm's law

    Proto-Germanic · c. 500 BCE (relative chronology secure; absolute date debated)

    *p *t *k → *f *θ *x · *b *d *g → *p *t *k · *bʰ *dʰ *gʰ → *β *ð *ɣ

  • High German consonant shift

    High German · c. 6th–8th century CE

    p t → pf ts · p t k → ff ss xx after vowels

Mayan

  • *r becomes y

    Yucatecan · c. 1st millennium BCE

    *r → y (*raax → yáax 'green'; K'iche' rax)

  • *r becomes t

    Mamean · c. 1st millennium CE

    *r → t (K'iche'an keeps r; Yucatecan has y)

Quechuan

Semitic

  • Initial *w becomes y

    Northwest Semitic · c. 2nd millennium BCE

    *w- → y- (*wald- → yeled 'child'; Arabic walad)

Turkic

Uralic

  • *k becomes a fricative

    Ugric · c. 2nd – 1st millennium BCE

    *k → *x / _ back vowel (*kala → hal, xul)

  • Initial *p becomes f

    Hungarian · Proto-Hungarian period (before c. 900 CE)

    *p- → f- (*pesä → fészek)

Uto-Aztecan

Vowel shifts

Parallel · 5 families

Vowels change quality: raising, fronting, breaking into diphthongs, or diphthongs smoothing into single vowels.

Germanic

Japonic

  • Mid vowels rise

    Northern Ryukyuan · c. 14th – 17th century CE

    *e → i · *o → u (ame → ami 'rain', kokoro → kukuru 'heart')

Semitic

  • The Canaanite shift

    Canaanite · By the 14th century BCE

    *ā → ō (*salām- → šālôm 'peace'; Arabic salām)

Turkic

  • Uzbek *a → o

    Karluk · Early modern period

    *a → o (*ata → ota 'father', *bar → bor)

Uralic

  • Proto-Saami vowel shift

    Saami · c. 1st millennium BCE

    *a → uo, with the other stressed vowels rotating (*kala → guolli)

Weakening and voicing

Parallel · 9 families

Consonants become voiced, fricative or weaker in particular positions, usually between vowels or after unstressed syllables.

Dravidian

  • Initial p becomes h

    Kannada · c. 12th – 13th century CE

    p- → h- (pālu → hālu 'milk'; Tamil pāl)

Germanic

  • Verner's law

    Proto-Germanic · After Grimm's law, before stress was fixed

    *f *θ *x *s → *β *ð *ɣ *z / after an unaccented syllable

  • Danish stop weakening

    East Norse · c. 13th – 15th century CE

    p t k → b d ɡ / V _ (weakened further in speech)

Japonic

  • p becomes h

    Japanese · c. 8th – 17th century CE

    *p → ɸ → h (pana → fana → hana 'flower')

Kra-Dai

  • Lao *r becomes h

    Southwestern Tai · c. 2nd millennium CE

    *r → h (Thai rɔ́ɔy : Lao hɔ́ɔy 'hundred')

Quechuan

Semitic

Turkic

  • *γ becomes w

    Kipchak · By the 11th – 13th century CE

    *γ → w / V_ (*taγ → taw 'mountain')

  • Initial voicing

    Oghuz · c. 11th – 13th century CE

    *t- *k- → d- g- (*taγ → dağ, *kel- → gel-)

  • *d becomes z

    South Siberian Turkic · Undated; after the Old Turkic period

    *d → z (*adaq → Khakas azax 'foot')

Uralic

  • Consonant gradation

    Finnic · c. 1st millennium CE

    kk pp tt → k p t · k p t → ∅ v d in closed syllables (kukka : kukan, pata : padan)

Uto-Aztecan

  • Numic consonant gradation

    Numic · Proto-Numic period

    medial C → fricative · geminate · nasal cluster, set by the preceding morpheme ('final features')

Mergers

Parallel · 7 families

Two sounds that were distinct fall together, and the old contrast survives only in related languages that kept it.

Austroasiatic

  • Voicing becomes register

    Khmeric · Middle Khmer period (c. 14th – 18th century)

    *b *d *ɡ → p t k, with the old voicing kept as a breathy second register on the vowel

Austronesian

Bantu

Japonic

  • Eight vowels become five

    Japanese · c. 8th – 10th century CE

    i₁ i₂ · e₁ e₂ · o₁ o₂ → i e o (8 vowels → 5)

Koreanic

Semitic

  • *ð merges with d

    Aramaic · Before the earliest inscriptions

    *ð → d (dəhav 'gold'; Hebrew zāhāv, Arabic ḏahab)

Sino-Tibetan

Loss

Parallel · 9 families

Sounds disappear: final consonants, unstressed vowels, or a consonant that leaves a lengthened vowel behind.

Algonquian

  • Odawa vowel syncope

    Ojibwe · 20th century

    short unstressed V → ∅ (Anishinaabe → Nishnaabe)

Austronesian

Bantu

Dravidian

  • Apical displacement

    South-Central Dravidian · Proto-South-Central Dravidian period

    V C(apical) … → C(apical) V … (*iraṇṭu → reṇḍu 'two')

Germanic

Pama-Nyungan

  • Initial dropping

    Paman · Proto-Northern-Paman period

    #C(V) → ∅, with later lenition of the new initial consonant

  • Initial consonants lost

    Arandic · Proto-Arandic period

    #C → ∅ · final V → ə (words now begin with a vowel)

Semitic

  • Loss of the gutturals

    East Semitic · Before and during the 3rd millennium BCE

    *ʔ *h *ḥ *ʕ *ġ → ∅, often with a → e (*baʕal- → bēlu)

  • Case endings lost in speech

    Arabic · c. 7th – 9th century CE

    -u -i -a (case vowels) → ∅ (kitābu → kitāb)

  • Amharic loses the gutturals

    Ethiosemitic · Before the earliest Amharic texts (14th century CE)

    *ʕ *ḥ *h *ʔ → ∅ or merged (kept in Tigrinya)

Sino-Tibetan

Turkic

  • Loss of initial *s

    Lena Turkic · Undated; before the modern records

    *s- → ∅ (*sub → uu 'water', *säkiz → aγïs 'eight')

Assimilation and strengthening

Parallel · 4 families

A sound takes on features of its neighbour (palatalisation, doubling) or hardens into a stronger consonant.

Dravidian

Germanic

Mayan

  • *k becomes ch

    Western Mayan · c. 1st millennium BCE

    *k *kʼ → ch chʼ (*kaq 'red' → chak; K'iche' kaq)

Uralic

Stress and prosody

Parallel · 6 families

Changes to where the accent falls, which in turn drive later loss and weakening.

Austroasiatic

  • Vietnamese tonogenesis

    Vietic · c. 6th – 12th century CE

    *-ʔ → rising · *-h (< *-s) → falling · voiced onsets → low register: 3 × 2 = 6 tones

  • Voicing becomes register

    Katuic · c. 1st – 2nd millennium CE

    *b *d *ɟ *g → p t c k + breathy register on the vowel

  • Voicing becomes register and tone

    Palaungic · c. 1st – 2nd millennium CE

    *b *d *ɟ *g → voiceless + register (Wa, Palaung) or tone (Angkuic)

Germanic

  • Stress fixed on the root

    Proto-Germanic · Late Proto-Germanic

    σ σ ˈσ → ˈσ σ σ (stress fixed on the root's first syllable)

Koreanic

Kra-Dai

  • The Great Tone Split

    Tai · c. 1000 – 1500 CE

    tones A B C (+ D) split by initial voicing → 5–9 tones; voiced initials devoice

Na-Dene

  • Tone from constriction

    Athabaskan · After the Proto-Athabaskan breakup

    V + constriction → V́ (high: Navajo) or V̀ (low: Gwich'in); Koyukon keeps no tone

Sino-Tibetan