A young visitor interacts with a baby hippopotamus swimming in its enclosure at the Berlin Zoo on January 1, 2018. Tourists and locals flocked to the zoo in the German capital on the unseasonably warm first day of the year. (Photo by Odd Andersen/AFP Photo)

Teenage girls are all steamed up these days about straight hair. The steam iron is replacing the huge rollers on which countless teens slept every night to achieve the height and curls fashionable until. The same girls endure having their hair stretched to absolute straightness on the ironing board, and then ironed to keep it that way. Unlike the roller setting, this takes teamwork. Gay Stilley, 14, goes through an ironing session with a couple of her friends at the Stilley Home in Glen Oaks, Queens, New York City on December 23, 1964. With a wary eye, Gay tries to watch the straightening process as one friend stretches her hair with a comb and another does the ironing, in the Stilley kitchen. (Photo by Marty Zimmerman/AP Photo)

This picture taken on January 6, 2018 shows macaque monkeys looking at a man's camera during snowfall at Wulongkou Nature Reserve in Jiyuan in China's central Henan province. (Photo by AFP Photo/China Stringer Network)

Kaye Don seated in the cockpit of his new racing car the “Silver Bullet” at Wolverhampton, England on February 21, 1930, in which he will attempt to beat world land speed record at Daytona. It has two 12-cylinder V shaped engines and each develops 2,000-h.p. The theoretical speed of the car is 275 m.p.h. but the designer estimated that will be able to reach 250 m.p.h. allowing for wind pressures. (Photo by AP Photo/Staff/Puttnam)

Competitors bear more than their bikinis during a spring break bikini contest at Summers' in Fort Lauderdale, Florida, USA circa 1985. (Photo by Nik Wheeler/Corbis via Getty Images)

Spot, a robot with dog-like movements, walks past a dog in Cathedral Square in Erfurt, Germany on April 20, 2021. Security service provider Ciborius, a provider of robotic security solutions with artificial intelligence, presented its artificial employee with high-resolution 360-degree all-round camera, ultra-bright LED light and a light detection system on Domplatz. (Photo by Michael Reichel/dpa)

A girl practices martial arts during a training at a school in Syrian opposition-held village of al-Jeineh, Syria on April 11, 2021. (Photo by Khalil Ashawi/Reuters)

A villager offers prayer to a dead body of an elephant, which is killed by lightning at atop of Bamuni hill in Assam's Nagaon district, on May 14, 2021. 18 wild elephants were found dead atop Bamuni Hills in Assam's Nagaon district today after lightning struck them during the showers in the area on May 12, 2021. At least 18 elephants are suspected to have been killed by lightning in northeastern India, officials said on May 13 as they launched a probe into the incident. (Photo by Biju Boro/AFP Photo)