最もっとも近ちかい共きょう通つう祖そ先せん

expression, noun

most recent common ancestor

Technical term in evolutionary biology and genetics, referring to the most recent individual from which all organisms in a group are directly descended.

• ヒトとチンパンジーの最もっとも近ちかい共きょう通つう祖そ先せんは約やく700ななひゃく万まん年ねん前まえに生いきていたと考かんがえられている。

  The most recent common ancestor of humans and chimpanzees is thought to have lived about 7 million years ago.