The paleobotanical record of Colombia: Implications for biogeography and biodiversity

• Main Authors: Hooghiemstra, H., Wijninga, V.M., Cleef, A.M.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2006
• Subjects: eastern-cordillera; high-andean biota; montane; northern andes; pliocene; pollen record; quaternary; rain-forest; south-america; tropical mountains; Antarctic; Austral; Antarc*
• Online Access: https://research.wur.nl/en/publications/the-paleobotanical-record-of-colombia-implications-for-biogeograp; https://doi.org/10.3417/0026-6493(2006)93[297:TPROCI]2.0.CO;2

Plant microfossil and macrofossil associations obtained from six dated sections from the area of the basin of Bogota¿ (2550 m, Eastern Cordillera, Colombia) show the evolution of the late Neogene Andean montane forest, triggered by the Andean orogeny. Progressive adaptation of warm tropical taxa to cool montane conditions, evolution of new neotropical montane taxa, and immigration of temperate Laurasian, Holarctic, and Austral-Antarctic elements gave shape to the present-day montane forest. Vegetational characteristics inferred from fossil plant associations reveal the altitude at the time of deposition. Neogene forests are floristically compared with contemporary forests at comparable altitudinal intervals in the surroundings of the Bogota¿ basin; however, the absence of taxa that had not yet arrived, or evolved, is most salient and shows that non-analogue plant communities are common. The main phases of montane forest development are: (1) pre-uplift phase of the late Miocene with abundant lowland taxa with tropical or neotropical affinities (Mauritia Kunth, Amanoa Aubl., Ceiba Miller, and representatives of Humiriaceae); montane forest rich in Podocarpaceae (potentially including Nageia Gaertn., Podocarpus L'He¿r., Prumnopitys Phil., and Retrophyllum C. N. Page) covered other previously uplifted areas in the region; (2) toward the early Pliocene the area was uplifted to ca. 1000 m; the relative proportion of temperate taxa of North American and southern South American stock increased and occupied the slopes of the low mountains; and (3) by the middle Pliocene uplift had proceeded to ca. 2000-2200 m and tropical lowland taxa, which are now restricted to altitudes below 1000 m, are no longer recorded in the fossil plant associations; the increase in the number of newly appearing montane taxa (Myrica L., Turpinia Vent., Gunnera L., Bocconia L., Gaiadendron G. Don f., Daphnopsis C. Martius, and Monnina Ruiz & Pav.) suggests a significant increase of diversity. Until the late Pliocene there is little to no ...