Star Trek: Picard showrunner Michael Chabon has explained why not all Romulans look alike.

Answering questions from fans on Instagram, Chabon highlighted how the physical differences between the two types of Romulans stems from their geographical location on the planet. "If you are referring to the forehead ridges, they are a facial feature common to the inhabitants of the northern hemisphere of Romulus," he explained. "Denizens of the Southern Hemisphere have smooth foreheads. There is an entire, quite scabrous vocabulary of mutual insult in the Romulan language based around this anatomical divergence."

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The third episode of the series, "The End is the Beginning," made reference to these differences between the Northern and Southern divide. In the episode, two Romulans live with Picard on his vineyard, each one featuring the recognizable facial characteristics of their region. When a Zhat Vash agent is captured and refuses to answer their questions, Laris -- who does not sport the forehead ridges -- highlights their prisoner's cranium, noting how he's a "stubborn Northerner."

Star Trek: Picard stars Patrick Stewart, Alison Pill, Michelle Hurd, Evan Evagora, Isa Briones, Santiago Cabrera, and Harry Treadaway. New episodes of the series premiere every Thursday on CBS All Access.

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(via ComicBook.com)