Brain-on-a-chip. Dazzling in green and magenta this image shows the nerve fibres (in green) produced by neural stem cells (in magenta) as they grow on a synthetic gel. Captured by a technique known as confocal microscopy, the image is part of research shedding light on how tinkering with the environment can affect the way in which nerve fibres grow. (Photo by Collin Edington and Iris Lee/Massachusetts Institute of Technology/Wellcome Images)
In this photograph taken on August 25, 2016, an Afghan shepherd watches over his sheep as they graze on the outskirts of Herat. (Photo by Aref Karimi/AFP Photo)
New Zealand singer and songwriter Kimbra Lee Johnson showed off her ageless appearance in a new photo shoot early February 2024. (Photo by Spencer Ostrander)
Jacob Yighe, right, attends the Met Gala Party for Jean Paul Gaultier x Shayne Oliver Group held at Sapphire in Manhattan on May 6, 2024. (Photo by Jeenah Moon for The Washington Post)
A demonstrator participates in a chant outside the Main Building on campus with hundreds of other students. Professors, students, and supporters of UT-Austin demonstrate on campus, Thursday, April 25, 2024, in Austin. (Photo by Ricardo B. Brazziell/Austin American-Statesman via AP Photo)
A girl covers her face as she is daubed in colours during the religious festival of Holi inside a temple in Nandgaon village, in the state of Uttar Pradesh, India, March 5, 2020. (Photo by Adnan Abidi/Reuters)
Recruits who earned a place in the Motivation Platoon struggle through water and muck on their way to becoming a Marine or going into some other line of work, October 7, 1971. (Photo by Eddie Adams/AP Photo)