Participants stretch their bodies as they pose for pictures before the Beijing International Marathon in Beijing, China, September 20, 2015. About 30,000 runners participated in the annual running event. (Photo by Kim Kyung-Hoon/Reuters)

Female body builders flex their muscles as they compete in the 2nd Women Sports Model contest in Guwahati on April 2, 2023. (Photo by Biju Boro/AFP Photo)

A mourner reacts as bodies of Palestinians killed in Israeli strikes lie at a hospital in Khan Younis in the southern Gaza Strip on October 17, 2023. (Photo by Mohammed Salem/Reuters)

Colombian-American actress and TV personality Sofía Vergara in the second decade of December 2023 flaunts her figure in a body-hugging dress. (Photo by Sofiavergara/Instagram)

“This brought me back. While I was doing my photo shoot this week for Muscle & Fitness, I could practically hear Joe Weider screaming, “Come on Arnold! What’s wrong with you? Pull in the stomach.” Watch for the issue in September!”

Sand from Montrose Beach whips past Vincent Lagrone as he walks along the lakefront October 19, 2011 in Chicago, Illinois. A high wind warning was issued for the city as winds between 40 and 45 mph are expected to cause 20- to 25-foot waves along sections of the lakefront. (Photo by Scott Olson/Getty Images)

A woman sits by a fountain in central Moscow, Russia on June 23, 2021. On June 23, 2021, daytime temperature is expected to reach +36°C (96.8°F). An orange weather warning has been issued due to the heat wave. (Photo by Sergei Fadeichev/TASS)

Sharon Beals is a San Francisco based photographer who has photographed nest and eggs specimens collected over the last two centuries at The California Academy of Sciences, The Museum of Vertebrate Zoology, and The Western Foundation of Vertebrate Zoology. While few nests are collected today, these nests and eggs are used for research, providing important information about their builder’s habitats, DNA, diseases and other survival issues.