In this September 16, 1983 file photo, actor and bodybuilder Arnold Schwarzenegger shows off his new U.S. citizenship papers as Maria Shriver, daughter of Sargent and Eunice Shriver, looks on at the Shrine Auditorium in Hollywood, Calif. (Photo by Wally Fong/AP Photo)

A girl looks from her flooded house on the outskirt of Kota Bharu in Kelantan December 29, 2014. The worst flooding in Malaysia in more than a decade has killed 10 people and forced nearly 160,000 from their homes and more rain is expected, authorities said on Sunday. (Photo by Athit Perawongmetha/Reuters)

A girl looks out from the window of a “La Sabana” tourist train in La Caro March 1, 2015. The “La Sabana” tourist train that runs through the capital was founded by Eduardo Rodriguez, a railway engineer. Rodriguez has worked on Colombia's railway system his whole life and now, with an air of nostalgia, transports thousands of tourists in renovated steam locomotives that he fixes in Bogota's Central Station which dates back to 1913. (Photo by Jose Miguel Gomez/Reuters)

Radin the Sunda pangolin hitches a ride on Nita as their keeper looks on. The elusive and nocturnal Sunda pangolin produces only one or two offspring a year and Radin is the third pangolin baby born in Night Safari since 2011. (Photo by Wildlife Reserves Singapore)

Whether they are the hunter or the hunted, these camouflage animals show natures incredible ability to blend in with its surroundings. Pictured perfectly concealed against their natural environment, the stunning pictures show the amazing lengths some animals will go to to stay out of sight. Here: The camouflage mappet moth looks like a fall lead in Switzerland. (Photo by Thomas Marent/Caters News/Ardea)

Juan Carlos Vilchez, 18-months-old, dressed to represent horror movie icon Chucky, looks into a storefront mall window, in Managua, Nicaragua, Friday, October 31, 2014. Juan Carlos is wearing a first place winner that he won earlier, for best Halloween costume in his age group. (Photo by Esteban Felix/AP Photo)

A boy looks back while he and another boy play on a Syrian military tank, destroyed during fighting with the Rebels, in the Syrian town of Azaz, on the outskirts of Aleppo, Sunday, September 2, 2012. (Photo by Muhammed Muheisen/AP Photo)

The Greater Sage-Grouse is certainly a formidable-looking bird. Being the largest grouse in North America and having tail feathers, which look like giant spikes, make for a ferocious sight. These birds are well known for their complicated courtship rituals, in which the males perform a special “strutting display” to attract the females. Another distinct feature of the Greater Sage-Grouse is two large yellow throat sacs (gular sacs), which are inflated by the males during the courtship display. Unlike pelicans, whose gular sacs are used to store fish while hunting, the throat sacks of the Greater Sage-Grouse are merely for display.