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

(L-R) Victoria's Secret models Lily Aldridge, Erin Heatherton, Adriana Lima, Candice Swanepoel, and Chanel Iman attend the Victoria's Secret debut of the New "Incredible" Bra at Victoria's Secret, SoHo on March 1, 2011 in New York City. (Photo by Andrew H. Walker/Getty Images). NEW YORK, NY – MARCH 01

A military AWAC aircraft lands at the British RAF Akrotiri airbase on March 20, 2011 in Cyprus. Defence analysts said the sovereign military airfield at Akrotiri could be used by the RAF to help enforce a no-fly zone over Libya against Col Gaddafi’s offensive against outgunned Libyan rebels. (Photo by Matt Cardy/Getty Images)

In the spring of 1965, within weeks of 3,500 American Marines arriving in Vietnam, a 39-year-old Briton named Larry Burrows began work on a feature for LIFE magazine, chronicling the day-to-day experience of U.S. troops on the ground – and in the air – in the midst of the rapidly widening war. The photographs in this gallery focus on a calamitous March 31, 1965, helicopter mission; Burrows’ “report from Da Nang”, featuring his pictures and his personal account of the harrowing operation, was published two weeks later as a now-famous cover story in the April 16, 1965, issue of LIFE.

Photo: Man your battle stations: The crew chief of helicopter Yankee Papa 13, lance corporal James C. Farley, mans an M-60 machine gun during a mission near Da Nang, Vietnam on March 31, 1965. (Photo by Larry Burrows/Time & Life Pictures)

“The Red River Hog (Potamochoerus porcus), also known as the Bush Pig (but not to be confused with P. larvatus, common name “Bushpig”), is a wild member of the pig family living in Africa, with most of its distribution in the Guinean and Congolian forests. It is rarely seen away from rainforests, and generally prefers areas near rivers or swamps.

Red River Hogs eat grass, berries, roots, insects, molluscs, small vertebrates and carrion. They are capable of causing damage to plantations. Red River Hogs typically live in herds of 6-20 members led by a dominant boar. Sows rear 3-6 piglets at a time.”

Photo: Two 17 day old red river hoglet twins forage for food next to their mother Bahiti at London Zoo on August 23, 2007 in London, England. Red River hoglets inhabit the forests and swamps of West and Central Africa. The recent additions to the London Zoo pig pen have been eagerly awaited by zoo keepers. (Photo by Chris Jackson/Getty Images)

“The Ainu (アイヌ?), also called Aynu, Aino (アイノ), and in historical texts Ezo (蝦夷), are indigenous people or groups in Japan and Russia. Historically they spoke the Ainu language and related varieties and lived in Hokkaidō, the Kuril Islands, and much of Sakhalin. Most of those who identify themselves as Ainu still live in this same region, though the exact number of living Ainu is unknown. This is due to ethnic issues in Japan resulting in those with Ainu backgrounds hiding their identities and confusion over mixed heritages. In Japan, because of intermarriage over many years with Japanese, the concept of a 'pure Ainu' ethnic group is no longer feasible. Official estimates of the population are of around 25,000, while the unofficial number is upwards of 200,000 people”. – Wkipedia

Photo: A captive bear drinking from a large bottle held by an Ainu tribeswoman. (Photo by Evans/Three Lions/Getty Images). Circa 1955

“The red panda (Ailurus fulgens, or shining-cat), is a small arboreal mammal native to the eastern Himalayas and southwestern China. It is the only species of the genus Ailurus. Slightly larger than a domestic cat, it has reddish-brown fur, a long, shaggy tail, and a waddling gait due to its shorter front legs. It feeds mainly on bamboo, but is omnivorous and may also eat eggs, birds, insects, and small mammals. It is a solitary animal, mainly active from dusk to dawn, and is largely sedentary during the day”. – Wikipedia

Photo: In this handout image provided by Taronga Zoo, Seba, a baby Red Panda, explores his new home at Taronga Zoo on April 7, 2011 in Sydney, Australia. The Red Panda cub was born at Christmas and is the 45th to be born at the zoo since 1977. (Photo by Peter Hardin/Taronga Zoo via Getty Images)

“Nicholas II (Russian: Николай II, Николай Александрович Романов, tr. Nikolay II, Nikolay Alexandrovich Romanov) (18 May [O.S. 6 May] 1868 – 17 July 1918) was the last Emperor of Russia, Grand Prince of Finland, and titular King of Poland. His official title was Nicholas II, Emperor and Autocrat of All the Russias and he is known as Saint Nicholas the Passion-Bearer by the Russian Orthodox Church. Nicholas II, his wife, his son, his four daughters, the family's medical doctor, the Tsar's valet, the Empress' lady-in-waiting and the family's cook were murdered in the same room by the Bolsheviks on the night of 16/17 July 1918”. – Wikipedia

Photo: Tsar Nicholas II (1868–1918) with his wife. (Photo by W. & D. Downey/Getty Images). Circa 1900