Malus sieversii Malus sieversii Malus sieversii is a wild apple native to the mountains of Central Asia in southern Kazakhstan. It has recently been shown to be the primary ancestor of most cultivars of the domesticated apple ("Malus pumila"). It was first described (as Pyrus sieversii) in 1833 by Carl Friedrich von Ledebour, a German naturalist who saw them growing in the Altai Mountains. It is a deciduous tree growing to , very similar in appearance to the domestic apple. Its fruit is the largest of any species of "Malus" except "pumila", up to 7 cm diameter, equal in size to many
Étienne-Louis Malus Étienne-Louis Malus Étienne-Louis Malus (; ; 23 July 1775 – 24 February 1812) was a French officer, engineer, physicist, and mathematician. Malus was born in Paris, France. He participated in Napoleon's expedition into Egypt (1798 to 1801) and was a member of the mathematics section of the Institut d'Égypte. Malus became a member of the Académie des Sciences in 1810. In 1810 the Royal Society of London awarded him the Rumford Medal. His mathematical work was almost entirely concerned with the study of light. He studied geometric systems called "ray systems", closely connected to Julius Plücker's "line geometry". He conducted