A small meadow pipit (left) is run off her feet as she tries to keep up with the demanding feeding schedule of an imposter - a larger cuckoo (right) on the Isle of Mull, Scotland in August 2022. (Photo by Graeme Cuerden/Solent News & Photo Agency)

Gentoo penguins begin the breeding season at Edinburgh Zoo on March 1, 2011 in Edinburgh, Scotland. The zoo keepers have just installed the nest rings in the penguin enclosure. The male penguins will then collect pebbles and offer them to the females to fill nest rings with, this helps keep the eggs and chick up off the ground and is part of their courtship display. (Photo by Jeff J Mitchell/Getty Images)ю EDINBURGH, SCOTLAND – MARCH 01

Dr. Marius Kruger (C) and memeber of the Kruger National Park keeps the head of a rhino up during a white rhino relocation capture on October 17, 2014. The Kruger National Park relocated four rhinoceros from a high risk poaching area to a safer area as part of ongoing strategic rhinoceros management plan. (Photo by Stefan Heunis/AFP Photo)

In this October 7, 2014, photo, Fredrick Brower, center, helps cut up a bowhead whale caught by Inupiat subsistence hunters on a field near Barrow, Alaska. Drawing on tradition, and keeping within the closely monitored Aboriginal subsistence whaling guidelines, a bowhead whale is carved and divided by a crew armed with knives and hooks, and then shared according to custom. (Photo by Gregory Bull/AP Photo)

Mike Branch helps customers shop for a Halloween masks at Fantasy Costumes on October 28, 2011 in Chicago, Illinois. The store, which had long lines at the registers at 4 AM this morning, is open around the clock through Halloween to help keep up with customer demand. Retailers nationwide are expecting record sales for Halloween merchandise this year with shoppers spending close to $7 billion dollars to celebrate the holiday. (Photo by Scott Olson/Getty Images)

A vendor sells fruits and nuts at the Green Bazaar in Almaty January 23, 2015. Kazakhstan is spending billions of dollars of its reserves to keep devaluation of its currency gradual and reduce inflationary risks of the sort thrown up in Russia by the rouble's slide, analysts and former central bank officials say. Kazakhstan, Central Asia's largest economy, is closely tied to Russia through trade and, like other ex-Soviet states, has been feeling the pain of the crisis which has driven the rouble down 50 percent against the dollar since the start of 2014. (Photo by Shamil Zhumatov/Reuters)

A member of the Hindu nationalist Rashtriya Swayamsevak Sangh (RSS) or the National Volunteers Association keeps watch from the top of a tree as others sit on the ground during their daylong camp on the outskirts of Pune, Maharashtra state, India, Sunday, January 3, 2016. Hindus, make up more than 80 percent of India's population of 1.25 billion. (Photo by Rafiq Maqbool/AP Photo)

(L-R) Edmea Pereira, 69, Elsa Rodrigues, 61, and Osmidio Conde, 71, take part in their surf class in Santos, Sao Paulo state, Brazil, March 16, 2016. When work is up, surf is up in Brazil, as a group of retired citizens take to the waves in keep-fit, keep-young sessions at a surf school in the city of Santos. The classes are run for free, three times a week at the Cisco Arana school, which aims to prove that age is just a number. (Photo by Nacho Doce/Reuters)