Proceedings of the National Academy of Sciences (PNAS)

Energy costs of Hannibal’s alpine crossing

Hannibal crossed the Alps with a large army containing 37 war elephants in 218 BC. Details of his route have scholars ...
PNAS

On the Riemann Hypothesis in Function-Fields

Note: The article usage is presented with a three- to four-day delay and will update daily once available. Due to ths delay, usage data will not appear immediately following publication. Citation ...
PNAS

EPIGENETIC CONTROL SYSTEMS

Aided by grants from the National Science Foundation. This essay is based on remarks given at a conference on “Extrachromosomal Heredity” held at Gif-sur-Yvette, France, in March, 1958. The conference ...
PNAS

Hamiltonian Systems and Transformation in Hilbert Space

Hamiltonian Systems and Transformation in Hilbert Space While generative AI has been shown to enhance productivity, its influence on learning new skills remains unclear. Our research examines the ...
PNAS

Evidence for the Existence of an Electro-Dynamic Field in Living Organisms

The President’s Council of Advisors on Science and Technology has called for a 33% increase in the number of science, technology, engineering, and mathematics (STEM) bachelor’s degrees completed per ...
PNAS

Mathematical misdefinition of adjusted cloud-fraction change limits isolation of aerosol effects

M. J. Kurowski, M. D. Lebsock, K. M. Smalley, The diurnal susceptibility of subtropical clouds to aerosols. Atmos. Chem. Phys. 25, 15329–15342 (2025). S. Qiu, X ...
PNAS

Social and spatial affinity drive wound care in ants

Social wound care plays a life-saving role in taxa as diverse as primates, ungulates, and insects. Yet the organizational principles that underlie this behavior remain unknown. In eusocial animals ...
PNAS

Three-stage melting of a macroscopic continuous spacetime crystal

Understanding how order emerges and breaks down is central to physics and materials science. Here, we demonstrate a macroscopic spacetime crystal—an ordered state periodic in both space and time—using ...
PNAS

Ferment to survive: How an aerobic bacterium persists during hypoxia

Join the global community of subscribers to PNAS, the flagship journal of the US National Academy of Sciences, a mission-driven nonprofit society. PNAS is one of the world's most-cited scientific ...
PNAS

Natural variation of CTS1 confers cold tolerance and blast resistance in rice

Enhancing multistress resilience in crops is vital for food security, yet the genetic basis for concurrent abiotic and biotic stress responses remains largely unknown. Here, we demonstrate that the ...
PNAS

In This Issue

Animal pollination benefits 75% of major crops and plays a crucial role in global food production. However, wild pollinators are declining in abundance and diversity. To examine how the decline in ...
PNAS

From molecular motors to chromosome architecture

From molecular motors to chromosome architecture Join the global community of subscribers to PNAS, the flagship journal of the US National Academy of Sciences, a mission-driven nonprofit society. PNAS ...