The Atlantic Puffin is definitely a curious-looking bird. The special coloring that this bird develops for the breeding season in the spring is very reminiscent of tropical birds. The bright colors of the beak and the markings around the eyes serve no particular advantage and have evolved as a result of sexual selection. However, Puffins don’t look that pretty all year round. They shed all these festive colors in partial moult after the breeding season is over. They lose the ornaments around their eyes, their face becomes darker, and their beak becomes very different. The natural habitat of these birds is the cold waters of the North Atlantic Ocean.

An old locomotive train that was used for transporting coal is preserved as a monument at Ny-Alesund, in Svalbard, Norway, October 11, 2015. A Norwegian chain of islands just 1,200 km (750 miles) from the North Pole is trying to promote new technologies, tourism and scientific research in a shift from high-polluting coal mining that has been a backbone of the remote economy for decades. (Photo by Anna Filipova/Reuters)

In a north London hospital, scientists are growing noses, ears and blood vessels in the laboratory in a bold attempt to make body parts using stem cells. It is among several labs around the world, including in the U.S., that are working on the futuristic idea of growing custom-made organs in the lab. (Photo by Matt Dunham/AP Photo)

Jan Agha, 49, an Afghan hunter, tries to catch his crane at a field in Bagram, Parwan province, Afghanistan on April 10, 2019. As the early morning light breaks over the plain north of Kabul, bird hunter Jan Agha checks his snares as he has done for the past 30 years, hoping to catch a crane, using a tethered bird to lure others down to the nets. (Photo by Mohammad Ismail/Reuters)

Visitors look at an artwork “Hierarchy of Prosperity” created by Indonesian artist Eko Nugroho during the VIP preview of the art fair “Art Basel” in Hong Kong, Tuesday, March 22, 2016. A set of gold-plated metal cubes, tapestries embroidered by unknown North Korean artisans and bales of cardboard waste are among the highlights of the Art Basel Hong Kong fair opening this week. (Photo by Kin Cheung/AP Photo)

Hornets are insects that are the largest eusocial wasps. Some species can reach up to 5.5 cm (2.2 in) in length. The true hornets make up the genus Vespa and are distinguished from other vespines by the width of the vertex (part of the head behind the eyes), which is proportionally larger in Vespa and by the anteriorly rounded gasters (the section of the abdomen behind the wasp waist). The best known species is the European hornet (Vespa crabro), about 2–3.5 cm in length, widely distributed throughout Europe, Russia, North America and Northeast Asia.

Gunung Leuser National Park is a national park covering 7,927 km² in northern Sumatra, Indonesia, straddling the border of North Sumatra and Aceh provinces. The national park, named after Mount Leuser (3,381 m), protects a wide range of ecosystems. An orangutan sanctuary of Bukit Lawang is located inside the park. Together with Bukit Barisan Selatan and Kerinci Seblat national parks it forms a World Heritage Site, Tropical Rainforest Heritage of Sumatra.

Wildlife are hunted down for consumption or for sale in the India eastern state of Nagaland. Hunters can make a good living, with some bred for food or to be sold as pets. These baby parrots, photographed by Caisii Mao via Sipa USA, are seen after they were caught and preserved by a local hunter and for sale at a private residence in Dimapur, India north eastern state of Nagaland on Wednesday, July 24, 2013. (Photo by Caisii Mao/NurPhoto/Sipa USA)