Environmental control of flowering periodicity in Costa Rican and Mexican tropical dry forests

摘要: Aim  We analyse the proximate causes of large variation in flowering periodicity among four tropical dry forests (TDF) and ask whether climatic or biotic interactions are ultimate periodicity. Location  The TDFs Guanacaste (Costa Rica), Yucatan, Jalisco Sonora (Mexico) characterized by a 5–7 month long season located along gradient increasing latitude (10–30°N). Methods  To dissect differences observed at community level, individual tree species were assigned to ‘flowering types’, i.e. groups with characteristic periods determined similar combinations environmental cues vegetative phenology. Results  Large fraction types blooming during wet season, respectively, indicates severity seasonal drought forests. In upland Jalisco, leafless trees remains suppressed severe is triggered first rains season. other forests, leaf shedding, exceptional rainfall daylength cause many deciduous various times well before summer rains. leafing out when largest Sonoran TDF. Main conclusions  wide-ranging phenotypic plasticity large. distinct temporal separation spring on shoots subsequent flushing represents unique adaptation development climates relatively short rainy Seasonal soil water availability apparently constitutes not only proximate, but also periodicity, which unlikely have evolved response adaptive pressures.