Medina 1990 (Article) Argentina

Eco-fisiologia y Evolucion de las Bromeliaceae

Author(s):—E. Medina

Publication:—Boletin de la Academia Nacional de Ciencias 59: 71-100. (1990)

Abstract:—Based on the anatomy and the prevalence of Bromeliaceae on the humid forest from the neotropical mountains and piedmont regions, different evolutive patems have been recognised. A bromeliaceous evolutive tree is proposed. The ancestral stock is suposed to be exclusively C3 in their metabolic pathway, belonging from an environment of hihg radiation and humidity. Such environment is, today, restricted to the Guiana and the tropical Andes. From there 3 different lines evolved independently, as it can be infered from adaptation toward arid zones or toward less radiated one. The most primitive members of each line -identified with subfamilies- bear the common characteristic of being C3 from a more or less humid area with high intensity of radiation. The most evolved types of each line exibit adaptation toward arid zones, developing the CAM pathway, or toward environment with less radiation. All Tillansioideae are epiphytic, so it is suposed that in their particular ancestral stock the epiphytic habit was allready established. Regarding Pitcairnioideae and Bromelioideae their ancestral stock were from terrestrial habitat. The Bromelioide line has a peculiar derivation from CAM of arid zones toward less arid and most umbrageous areas.