The blue-footed booby (Sula nebouxii) is a marine bird in the family Sulidae, which includes ten species of long-winged seabirds. Blue-footed boobies belong to the genus Sula, which comprises six species of boobies. It is easily recognizable by its distinctive bright blue feet, which is a sexually selected trait. Males display their feet in an elaborate mating ritual by lifting their feet up and down while strutting before the female.

A member of the “Exit Point” amateur rope-jumping group jumps from a 44-metre high (144-feet high) waterpipe bridge in the Siberian Taiga area outside Krasnoyarsk, September 28, 2014. Fans of rope-jumping, a kind of extreme sport involving a jump from a high point using an advanced system of amortization including mountaineering and rope safety equipment, attended the Golden Autumn group's jumping season. (Photo by Ilya Naymushin/Reuters)

A rider holds on as a bull tries to throw him during the Bull Ride Spectacular on the first day of the 2014 Deni Ute Muster at the Play on the Plains Festival grounds on October 3, 2014 in Deniliquin, Australia. (Photo by Mark Kolbe/Getty Images)

Doesn’t taking a nap in a hammock outdoors sound lovely? Perhaps not when you’re hanging in the air, thousands of feet above ground, between two mountains in the Italian Alps! Which is exactly what these adventurous folks did during the International Highline Meeting in Monte Piana, Italy. (Photo by Sebastian Wahlhuetter Photography)

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)

An Israeli boy looks through the sight of a weapon during a display of Israeli Defense Forces (IDF) equipment and abilities at the West Bank settlement of Kiryat Arba, April 23, 2015, during celebrations for Israel's Independence Day, marking the 67th anniversary of the creation of the state. (Photo by Ronen Zvulun/Reuters)

An elephant “kisses” a visitor during a show at an elephant training school in Xishuangbanna, Yunnan province, April 18, 2015. Some 16 elephants live at the school and give four 30-minute performances everyday for visitors. (Photo by Wong Campion/Reuters)

Angora rabbit Emilson sits next to its freshly shaved hair at Georgia Spausta's small farm in Herzogbirbaum, Austria March 10, 2015. Spausta produces hand-spun yarn from some 25 angora rabbits which is sold in small scale to enthusiasts or at local markets. The rabbits are clipped four times a year, each time giving some 300 grams of wool, about the amount needed to knit one pullover. (Photo by Heinz-Peter Bader/Reuters)