fill out = 余白、空白を埋める、充たす、

Last week, researchers welcomed the newest long-gone relative: Homo luzonensis. Here’s a quick guide to some of the other archaic humans that filled out the branches on our evolutionary tree, and what we have learned from them.

Fossils fill out our family trees - by Nicholas St. Fleur NYT April 17 2019 先人類

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