PNAS Science Sessions

Chinmay Kalluraya and Matthew Daugherty explain how vertebrates acquired a gene critical for vision from bacteria.

Blair P. Bentley, Lisa Komoroske, and Camila Mazzoni discuss the role genomic elements play in the evolution of sea turtles.

A special edition of Science Sessions delves into the capabilities of robots inspired by plants and animals.

Stanislas Dehaene and Marie Amalric investigate whether short online videos are sufficient to teach mathematics concepts.

Anna Lea Albright and Peter Huybers describe how optical effects consistent with air pollution appear in the paintings of Claude Monet and J.M.W. Turner.

Kristin Winchell explains the genetic basis of anole adaptation to urban environments.

Researchers document animal extinctions in the Ediacaran Period that may have preceded the earliest known mass extinction.

Bo Wang and Chunpeng Xu describe how fossilized katydids provide insight into the role of insect sounds in the Mesozoic.

Tom McGrath describes how the neural network AlphaZero taught itself how to play chess without observing a human game.

Orit Peleg, Golnar Fard and Francisco López Jiménez explain how honeybees overcome geometric constraints to construct honeycombs.