Alexander Eig was one of the first botanical researchers to work in Israel. He served as head of the botany department at the Hebrew University in Jerusalem and co-founded the Jerusalem Botanical Garden on Mount Scopus.

Born near Minsk, Belarus, Eig spent his childhood surrounded by forests. Aged 15 he moved to Palestine, enrolling in the Mikveh Israel agricultural school.

In 1925, at the invitation of Otto Warburg, Eig joined the staff of the agricultural experimental station in Tel Aviv. It was here that he began to work with his long-time collaborator, Michael Zohary, and met his future wife, Itta Faktorovsky, sister of his friend and fellow botanist Elazar Faktorovsky. The station moved to Jerusalem in 1926, under the auspices of the Hebrew University.

Receiving his PhD in 1931, Eig founded the Jerusalem Botanical Gardens with Zohary and Naomi Feinbron. Together they published The Analytical Flora of Palestine in the same year. Eig's other significant publications included "On the Vegetation of Palestine" (1927, in the Bulletin of the Agricultural Experiment Station, Tel Aviv, 7) and Systematic Studies on Astragali of the Near East (published posthumously in 1955).

In 1937 Eig was invited by Yitzhak Ben-Zvi to testify before the Peel Commission, on the question of whether the country could sustain a large population. He was later asked to prepare a map that would serve the arguments of the Zionist side in the international arena.Eig died of cancer in 1938, at less than 44 years of age. He was buried in the cemetery on the Mount of Olives, where his headstone reads "The creator of plant science in Israel".