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 period of relative stability has put the Iranian capital No1 on the list of world cities that have achieved biggest improvements in liveability over the past five years, as calculated by the Economist Intelligence Unit. The “most improved” top 10 contains some unexpected names. So, eg, the fourth place: Abidjan, Ivory Coast. Latest ranking: 128; Ranking five years ago: 131; Five-year index movement: 3.8%. Here: A supporter of Ivory Coast president Alassane Ouattara campaigns in a market in the city’s Koumassi quarter. (Photo by Sia Kambou/AFP Photo)

People manoeuvre into position as they take part in a mass nude art installation entitled Sea of Hull by New York based artist Spencer Tunick in Hull, England, Saturday July 9, 2016. (Photo by Danny Lawson/PA Wire via AP Photo)

“March 19, 2012 was the first rehearsal for the Victory Day Parade at the training ground in Alabino (near Moscow, Moscow Military District). Since the end of February troops and vehicles from various units and formations of the Armed Forces began arriving to Alabino training ground. The first rehearsal included only military vehicles. During the ride the average speed of vehicles is 12 km/h, the distance depending on the type of vehicle from 12 to 15 meters”. – Vitaly Kuzmin

Actors perform “The Passion of Jesus” to crowds in Trafalgar Square on April 22, 2011 in London, England. The actors come from the Wintershall Estate in Surrey where they also perform a Nativity play in and around the farm buildings at Christmas. (Photo by Peter Macdiarmid/Getty Images)

In preparation for the Dubai Duty Free Men's Open, Andre Agassi and Roger Federer of Switzerland, couldn't resist the temptation to have a friendly “hit” on the world's most unique tennis court, the Helipad of the Burj Al Arab, the world's most luxurious hotel. Standing 321 metres high on a man made island, the majestic Burj Al Arab is without doubt the most recognizable hotel in the world. The hotel's helipad, which is situated 211 metres high covers a surface area of 415 square metres. The pictures were taken on February 22, 2005, in Dubai, United Arab Emirates. (Photo by Getty Images for Dubai Duty Free)

Playful seals. The pair of playful seals swim around each other. Two passionate seals were captured on camera in a tender embrace by underwater photographer Robert Bailey, 50, near the Farne Islands off the Northumberland coast, UK. (Photo by Robert Bailey/Medavia)

Painter Alexander Zavala residing in Gelendzhik, painted in the style of a historical series of paintings about animalism epic cats.