Stunning images taken by Sean Lenz, 19, and Kristoffer Abligaard, 20, show picturesque waterfalls transformed into vibrant rainbows of colour. The awe-inspiring images were created by clever use of long exposure photography and glow sticks floating through water. Photo: Picturesque waterfalls transformed into rainbows of colour. (Photo by Sean Lenz/Kristoffer Abildgaard)

Hucul horses play in the wild meadows and forests near Odrzychowa in southeastern Poland on October 18, 2014. Huculs, a primitive breed of horse, escaped total extinction due to the efforts of scientists and Polish farmers. (Photo by Janek Skarzynski/AFP Photo)

Jackie Galarza greets the Camarasaurus dinosaur held by Houston Ferguson during the “Jurassic Quest” experience at Broward County Convention Center on July 08, 2022 in Fort Lauderdale, Florida. Fans of dinosaurs can walk through moving and roaring animatronic replicas of the now extinct creatures during the three-day event. (Photo by Joe Raedle/Getty Images)

Leo, an orphaned Sumatran orangutan, is taken to the Sumatran Orangutan Conservation Programme rehabilitation centre. Leo will join other orangutans who have been reintroduced to the Pinus Jantho nature reserve. The SOCP has gradually formed a completely new wild population of species that have been threatened with extinction. (Photo by Sutanta Aditya/Barcroft Images)

The tusk of a woolly mammoth that lived some 18,000 years ago, from which researchers sequenced the extinct mammal's entire genome, is seen in northeastern Siberia in this photo from 2015. (Photo by Love Dalen/Handout via Reuters)

A calico sits in its enclosure and suns itself in Hessen, Germany on May 28, 2021. The Opel Zoo presents a walk-in Madagascar aviary for caltas and varis. The primate species is native to Madagascar and is threatened with extinction. (Photo by Andreas Arnold/dpa)

A demonstration of Extinction Rebellion in Amsterdam, the Netherlands, has been dissolved by the local triangle (police, judiciary and mayor), February 26, 2021. About eighty activists, some of whom scantily dressed, blocked the Overtoom in Amsterdam-West. About twenty of them do not want to leave, they are taken away elsewhere. (Photo by Koen van Weel/EPA/EFE)