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MENTAL MODEL · M0010

Signor-Lipps Effect

Signor-Lipps Effect
TechnicalHigh supportPaleontology
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Version 1.0.0 · Updated 2026-07-28

CORE DEFINITION

The Signor–Lipps effect concerns temporal bias from incomplete fossil sampling: the youngest known fossil need not represent a taxon’s last surviving organism. Simultaneous extinctions can consequently appear staggered. It is not Signorelli name-forgetting or retrieval interference.

SCAFFOLDING EFFECT

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Distinguish the last observation from the actual end, and assess whether missing samples affect conclusions about extinction timing and pace.

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Limited fossil preservation and discovery can leave the final interval unsampled. Differences in sampling and preservation across taxa can spread out their observed last appearances despite simultaneous extinction.

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Source support: Explicit

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    en.wikipedia.orghttps://en.wikipedia.org/wiki/Signor%E2%80%93Lipps_effectZH · Explicit
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