Taking the temperature of punctuated equilibrium on its semicentennial

Abstract While punctuated equilibrium is foundational to modern paleobiology, the degree to which paleontologists and evolutionary biologists understand its claims and implications is not clear. Many critiques of punctuated equilibrium are based on misinterpretations of the model, and these misconceptions are likely to be common in classrooms. To begin to understand how the paleontological and evolutionary biology communities, including students, educators, researchers, and museum staff, perceive punctuated equilibrium, we distributed a preliminary exploratory survey to assess how respondents use punctuated equilibrium in their research and teaching and how well they comprehend its core ideas. This pilot study was undertaken to identify possible areas for future research, as well as to assess initial patterns in the data that might indicate the need for a more rigorous follow-up investigation, for example, with a formal validated survey instrument. Among this exploratory sample of 122 respondents, a strong consensus emerged that punctuated equilibrium is important to both paleontology and evolutionary biology and should be included in textbooks. However, while punctuated equilibrium is taught in both introductory and upper-level courses, most instructors in the sample spend 1 week or less on the topic. Survey items designed to explore respondents’ understanding of core ideas within punctuated equilibrium revealed internally inconsistent responses, with a notable lack of consensus on many items. Response data suggest that both empirical (e.g., anagenesis is a common phenomenon) and conceptual (e.g., punctuated equilibrium states that morphological change occurs within just a few generations during speciation) misconceptions may be common. These potential misconceptions are held by the surveyed paleontologists and evolutionary biologists alike, in all career stages. Despite 50 years of discussion, our survey results suggest the lack of a shared understanding of punctuated equilibrium within this scientific community. We therefore provide some initial guidance and concrete strategies to improve teaching and learning about punctuated equilibrium and propose areas for further investigation.