Author: Jeanne Wacker

What is this generation of AI good at and where does it fall short? Ira Flatow, host and producer of Science Friday, talks to Melanie Mitchell, alumni fellow (1990-92) and professor at the Santa Fe Institute, about apps like ChatGPT and Lensa, deep fakes, and other current issues with artificial intelligence. Listen to Science Friday.

David Polly, alumni fellow (1994-96) and professor of earth and atmospheric sciences at Indiana University, co-authored a PNAS article that examines the functional relationship between mammal locomotor traits and the environment. Read the complete PNAS article.

Abstract: We are in a modern biodiversity crisis that will restructure community compositions and ecological functions globally. Large mammals, important contributors to ecosystem function, have been affected directly by purposeful extermination and indirectly by climate and land-use changes, yet functional turnover is rarely assessed on a global scale using metrics based on functional traits. Using ecometrics, the study of functional trait distributions and functional turnover, we examine the relationship between vegetation cover and locomotor traits for artiodactyl and carnivoran communities. We show that the ability to detect a functional relationship is strengthened when locomotor traits of both primary consumers (artiodactyls, n = 157 species) and secondary consumers (carnivorans, n = 138 species) are combined into one trophically integrated ecometric model. Overall, locomotor traits of 81% of communities accurately estimate vegetation cover, establishing the advantage of trophically integrated ecometric models over single-group models (58 to 65% correct). We develop an innovative approach within the ecometrics framework, using ecometric anomalies to evaluate mismatches in model estimates and observed values and provide more nuance for understanding relationships between functional traits and vegetation cover. We apply our integrated model to five paleontological sites to illustrate mismatches in the past and today and to demonstrate the utility of the model for paleovegetation interpretations. Observed changes in community traits and their associated vegetations across space and over time demonstrate the strong, rapid effect of environmental filtering on community traits. Ultimately, our trophically integrated ecometric model captures the cascading interactions between taxa, traits, and changing environments.

Citation: Short, Rachel A., Jenny L. McGuire, P. David Polly, and A. Michelle Lawing. “Trophically integrated ecometric models as tools for demonstrating spatial and temporal functional changes in mammal communities.” PNAS, 120 (7) e2201947120. https://doi.org/10.1073/pnas.2201947120.

Ben Green, research fellow (2020-23) and assistant professor of public policy, authored an article in Philosophy and Technology in which he argues that promoting justice with algorithms requires reforming the methodology of algorithmic fairness. Read the full article.

Abstract: Efforts to promote equitable public policy with algorithms appear to be fundamentally constrained by the “impossibility of fairness” (an incompatibility between mathematical definitions of fairness). This technical limitation raises a central question about algorithmic fairness: How can computer scientists and policymakers support equitable policy reforms with algorithms? In this article, I argue that promoting justice with algorithms requires reforming the methodology of algorithmic fairness. First, I diagnose the problems of the current methodology for algorithmic fairness, which I call “formal algorithmic fairness.” Because formal algorithmic fairness restricts analysis to isolated decision-making procedures, it leads to the impossibility of fairness and to models that exacerbate oppression despite appearing “fair.” Second, I draw on theories of substantive equality from law and philosophy to propose an alternative methodology, which I call “substantive algorithmic fairness.” Because substantive algorithmic fairness takes a more expansive scope of analysis, it enables an escape from the impossibility of fairness and provides a rigorous guide for alleviating injustice with algorithms. In sum, substantive algorithmic fairness presents a new direction for algorithmic fairness: away from formal mathematical models of “fair” decision-making and toward substantive evaluations of whether and how algorithms can promote justice in practice.

Citation: Green, B. Escaping the Impossibility of Fairness: From Formal to Substantive Algorithmic Fairness. Philos. Technol. 35, 90 (2022). https://doi.org/10.1007/s13347-022-00584-6

What if we lived in a world without credit? Downside Up host Chris Cillizza discusses the complicated history of credit with alumni fellows Sarah Quinn (2010-12), who is an associate professor of sociology at the University of Washington, and Monica Prasad (2000-03), who is a professor of sociology at Northwestern University. Along with New York Times business reporter Emily Flitter, they explore the American economy, credit cards, loans, and other facets of the financial system. Listen to the Downside Up episode.

Joseph Feldblum, alumni fellow (2018-22) and assistant research professor of evolutionary anthropology at Duke University, co-authored an article investigating the predictors of gestation length, and the impact of gestation length on offspring survival, in chimpanzees, humans’ closest living relatives. They found that like humans, chimpanzees had shorter gestations after short inter-gestational intervals, and short gestations were associated with higher offspring mortality. Read the full article in the American Journal of Biological Anthropology.

Abstract:

Objectives
Energetics are widely recognized to influence timing of birth in humans and other eutherian mammals, yet considerable variation exists in the relationship between energetic constraints and gestation length. In humans, poor nutrition and short inter-gestational intervals (IGIs) are associated with shorter gestations. In other mammals, lower energy availability is usually associated with longer gestations. We investigated the predictors of gestation length, and the impact of gestation length on offspring survival, in chimpanzees, humans’ closest living relatives.

Materials and Methods
We used 50 years of demographic and behavioral data to estimate gestation lengths in the wild chimpanzees of Gombe National Park, Tanzania, and then used ecological and demographic data to explore the predictors and consequences of gestation length in our sample.

Results
Gestation lengths were shorter for females in their early 30s (relative to younger and older females), and after short IGIs. Other predictors potentially associated with maternal energetic condition and maternal investment were not associated with gestation length. We also found that shorter gestation lengths corresponded to lower offspring survival.

Discussion
Like humans, chimpanzees had shorter gestations after short IGIs, and short gestations were associated with higher offspring mortality. We consider competing explanations for the conflicting relationships between energetics and gestation length across eutherian mammals in light of these results.

Citation: Feldblum, J. T., Boehm, E. E., Walker, K. K., & Pusey, A. E. (2022). Predictors and consequences of gestation length in wild chimpanzees. American Journal of Biological Anthropology, 179( 3), 417– 430. https://doi.org/10.1002/ajpa.24601

In 1935, W.E.B. Du Bois published Black Reconstruction in America: An Essay Toward a History of the Part which Black Folk Played in the Attempt to Reconstruct Democracy in America, 1860–1880. At that time, The American Historical Review did not review the book because the editors did not recognize it as history. The journal is reckoning with racist aspects of its work and influence; 88 years later, Elizabeth Hinton, alumni fellow (2012-14) and associate professor of history and African American studies at Yale University, writes the long overdue review. Read The Last Great Battle of the West.

Citation: Elizabeth Hinton, “The Last Great Battle of the West”, The American Historical Review, Volume 127, Issue 4, December 2022, Pages 1909–1915, https://doi.org/10.1093/ahr/rhac454

Max Lifchitz, alumni fellow (1974-77), composer, and professor of music at SUNY-Albany, to offer a recital featuring eight distinctive works inspired by diverse aspects of the natural world. Composers included in the event hail from Italy, Mexico, Nigeria, and throughout the US.

Event Time/Date: February 5, 2023 at 7:30 PM.

Access livestream.

Congratulations to Peter Wilf, alumni fellow (1999-02) and professor of geosciences at Penn State University, on being named as one of the American Association for the Advancement of Science (AAAS) 2022 fellows! AAAS is the largest general science society. This year it recognized 506 scientists, engineers, and innovators for their distinguished scientific and social achievements. Peter is recognized for his contributions to research in paleobotany.