A visitor holds an Israeli-made rifle during the 8th International Land and Naval Defense system exhibition, in New Delhi, India, on February 6, 2014. (Photo by Anindito Mukherjee/Reuters)

An artist has discovered a bizarre way to create his work – by coating the feet of insects with paint who then crawl across the canvas creating intricate pieces of art. (Photo by Caters News)

A two-horse team street cleaner, with sprayer, squeegee, and roller at rear. New York, between ca. 1910 and ca. 1915. (Photo by NYC Municipal Archives)

Artist Vik Muniz is known for his gigantic composite installations and sculptures created from thousands of individual objects. In this new collaboration with artist and MIT researcher Marcelo Coelho, Muniz takes the opposite approach and explores the microscopic with a new series of sandcastles etched onto individual grains of sand.

Meet the star students of orangutan school – the unique rehab centre where orphaned apes are taught how to climb trees and survive in the wild without their mum and dad. (Photo by Caters News)

People feed the birds in Battery Park in the Manhattan borough of New York, December 18, 2014. Hart has been feeding the birds three times a week for the last three years. (Photo by Carlo Allegri/Reuters)

A labourer packs incense in preparation for Tet, the traditional Vietnamese lunar new year, in Hong Chau village, outside Hanoi January 29, 2015. Tet is from February 14 till 24. (Photo by Reuters/Kham)

A runner taking part in the 38th Annual Empire State Building Run-Up is pictured arriving on the 86th floor in the Manhattan borough of New York February 4, 2015. (Photo by Carlo Allegri/Reuters)