A Hawaiian cleaner wrasse provides its cleaning services to a yellowfin goatfish in a reef community off the Big Island in Hawaii. Cleaner species help rid their hosts of ectoparasites, dead tissue, bacteria and fungi. Studies have shown cleaning to play a vital role in keeping many reef ecosystems healthy. (Photo by Marty Snyderman/Caters News Agency)

Couples take part in the “Love and Challenge Marathon” in Hanoi, Vietnam, 16 August 2015. Fifty couples, who are going to get married, participated in the event which is held the fifth time. This year, the winners of the marathon received a honeymoon trip to Malaysia. (Photo by Luong Thai Linh/EPA)

Peru, Iquitos. Restaurant in Bellavista, an area by the Amazon on April 2005. (Photo by Jean-Claude Coutausse)

A frozen public bench is seen next to a lake side due to the heavy wind conditions in Geneva February 8, 2015. (Photo by Pierre Albouy/Reuters)

A Pakistani vendor prepares peanuts for sale on a roadside in Peshawar, Pakistan, 01 January 2018. After a good raining season the sales of dry fruits flourish in the country. Tourists from all over Pakistan come to Peshawar to purchase dry fruits along with other items because of price differences between different parts of the country. (Photo by Bilawal Arbab/EPA/EFE)

Relatives of community leader Josemano “Badou” Victorieux, one of the victims of clashes with the Police, cry during his funeral in Port-au-Prince, Haiti, 16 October 2019. The protest movement in Haiti completes a month with no sign of remitting and without the President, Jovenel Moise, yielding to the voices that require him to resign. (Photo by Orlando Barria/EPA/EFE)

A Kashmiri man cover his head with plastic bag as it snows in Srinagar, Indian controlled Kashmir, Thursday, November 7, 2019. The region received its first snow on Wednesday, bringing temperatures down drastically and affecting air and vehicular traffic. (Photo by Mukhtar Khan/AP Photo)

The tempestuous stellar nursery called the Carina Nebula, located 7,500 light-years away from Earth in the southern constellation Carina. (Photo by Reuters/NASA)