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Glite Dictionary
polytomy

polytomy

9.9
A place in a tree where more than two branches come from one ancestor, showing the relationships are not clear
  • noun
  • /ˌpɒlɪˈtoʊmi/
  • Specialized
translation icon : politomía
  • In the phylogenetic tree, the researchers identified a polytomy indicating multiple possible ancestors for the species.

Examples

  • Sadly, though, it appears I resolved little more than a polytomy.

    Blog text (29)

  • I resolved little more than a polytomy.

    Blog text (29)

  • The study of evolutionary relationships revealed a polytomy that complicated the classification of the organisms.

  • During the analysis of the genetic sequences, a polytomy was observed, highlighting the uncertain links between the groups.

How Many Branches

polytomy
  • Specialized
9.9
bifurcation
  • Formal
6 8.6

Surface Forms

polytomy singular
polytomies plural

Morphology

polytomy = poly + tom + y

The word is built from poly- 'many' plus a classical root meaning 'cut/divide', but the phylogenetics sense is specialized and not immediately obvious to a B1 learner.

Etymology

The word polytomy breaks into poly- meaning 'many' and -tomy meaning 'cut', as in polygon, which has many sides, and anatomy, which is about cutting to study the body. So a polytomy is like one point with 'many cuts' or branches coming out, and that image explains why it shows several groups from a single ancestor and often means we are not sure about their exact relationships.