collection of geological and botanical samples and established a library. Aaronsohn served as a scientific consultant to Djemal Pasha during a crop-destroying desert locust invasion in 1915. In March–October of that year, the locusts stripped the country of almost all vegetation. Aaronsohn and the team fighting the locust invasion was given permission to move around the area known as Southern Syria (including modern day Israel) and made detailed maps of the areas they surveyed. Aaronsohn also collected strategic information about Ottoman camps and troop deployment. In 1918, Aaronsohn was one of the experts consulted for the purpose of demarcating the northern boundary of Palestine, focusing on the need for irrigation water. He envisaged a boundary that would assure the inclusion of the sources of the Jordan, Litani and Yarmuk rivers. His approach became the official Zionist baseline presented to the Peace Conference in Paris in February 1919. Political activity and espionage During World War I, the Ottomans had joined sides with the Germans, and Aaronsohn feared the Jews would suffer the same fate as the Armenians under the Turks. Together with his assistant Avshalom Feinberg, his sister Sarah Aaronsohn and a few others, Aaronsohn organized Nili, a ring of Jewish residents of Palestine who spied for Britain during World War I. He recommended the plan of attack through Beersheva that General Edmund Allenby ultimately used to take Jerusalem in December 1917 as part of the Sinai and Palestine Campaign. Owing to information supplied by Nili to the British Army concerning the locations of oases in the desert, General Allenby was able to mount a surprise attack on Beersheba, bypassing strong Ottoman defenses in Gaza. In 1917, Chaim Weizmann sent Aaronsohn on a political campaign to the USA. While there, Aaronsohn learned that the Ottoman authorities had intercepted a Nili carrier pigeon, which led to the arrest and torture of his sister Sarah and other members of the underground. Death and legacy After the war, Weizmann called on Aaronsohn to work on the Versailles Peace Conference. On 15 May 1919, under unclear circumstances, Aaronsohn was killed in an airplane crash over the English Channel while on his way to France. Some blamed the British government. Aaronsohn died a bachelor and had no children. His research on Palestine and Transjordan flora, as well as part of his exploration diaries, were published posthumously. After Aaronsohn's death, the director of British Military Intelligence confirmed