Study Identifies How Squid Have Evolved to See in Dim Ocean Water

In a new paper published in Science, research led by postdoctoral fellow Jing Cai and Alison Sweeney, an assistant professor of Physics and Astronomy, provided a detailed look into how self-assembled squid lenses have evolved to adjust for light distortion, which allows them to see clearly in the dim waters of the open ocean.

In addition to contributing to the field of nanotechnology by outlining self-assembly at the nanometer length scale, the research could one day help scientists build improved artificial lenses that can focus light perfectly. It could also allow them to better understand cataracts, a clouding of the human eye lens that leads to blurred vision.​​​​​​​​​​​​​​

“In biology,” Sweeney says, “you're dealing with proteins, DNA and RNA, not Lego bricks. Our analog for Lego bricks in this study was the individual proteins that make up the refractive material in the lens. We found that squid have a really elegant optical design whereby having a very dense material in the center, made of proteins with lots of linkage sites, and a very sparse material on the edge, made of proteins with two linkage sites, they can form a spherical lens that doesn't suffer from spherical aberration. This work was a really nice case study that enabled us to talk about the evolution of self-assembly, or how evolution invents new materials through a random process, in detail, without needing to be speculative about it.”

Click here to read the full article.

Arts & Sciences News

John Lapinski to be named the Robert A. Fox Leadership Professor of Political Science

John Lapinski will be named the Robert A. Fox Leadership Professor of Political Science and the director of the Robert A. Fox Leadership Program effective July 1, 2018.

View Article >
Recipients of the 2018 Penn Prize for Excellence in Teaching by Graduate Students Announced

Eight graduate students from Penn Arts and Sciences to receive the prestigious award.

View Article >
Joseph S. Francisco Named President’s Distinguished Professor of Earth and Environmental Science

Joseph S. Francisco will join Penn as the President’s Distinguished Professor of Earth and Environmental Science, with a secondary appointment in the Department of Chemistry, on July 1, 2018.

View Article >
Michael C. Horowitz Awarded Department of Defense Grant to Lead Team on Study of Autonomous Systems and AI

Michael C. Horowitz, Professor of Political Science, will oversee the study of autonomous systems and artificial intelligence.

View Article >
Earthquakes at the Nanoscale

In collaboration with Robert Carpick and David Goldsby, Tian, who graduated from Penn in 2017 with a doctorate in physics, recently published a paper in Physical Review Letters which attempts to tackle these devastating natural phenomena by investigating the laws of friction at the smallest possible scale, the nanoscale.

View Article >
Doris Wagner Named Robert I. Williams Term Professor

A leader in the fields of plant biology, chromatin modification, and epigenetics, Wagner’s research focuses on understanding at the molecular level the complex changes that occur when an organism switches developmental programs.

View Article >