An Overview of the Fossil Record of Climbers: Bejucos, Sogas, Trepadoras, Lianas, Cipos, and Vines.
Revista Brasileira De Paleontologia
One of the most obvious life forms in tropical forests today is the liana, which laces together tree canopies and climbs the dark interiors of forests with snake-like stems. Lianas are ecologically important in extant, forested ecosystems, both intact and disturbed. Their contribution to forest diversity, food resources, structural complexity, and plant-animal interactions are recognized, but rarely studied. Climbers (woody lianas and herbaceous vines) are viewed as everything from diversity contributors to forest growth inhibitors by modern ecologists and systematists. Climbers take advantage of the structural support of trees to invest proportionately more in vegetative and reproductive organs, resulting in proliferation at the individual and species level. Today the climbing habit is dominated by angiosperm species, with only a minor contribution from ferns plus a single non-angiosperm seed plant genus, Gnetum. This contribution reports the establishment of the newly established database, Fossil Record of Climbers (FRC) that documents more than 1100 records of climbing plants from the Paleozoic to the Quaternary using published literature on the fossil record. The diversity of climbers in the fossil record prior to the evolution of angiosperms is explored, posing the hypothesis that climbers of the past had a similarly important role in tropical forests, at least in the Paleozoic. The extinct Paleozoic pteridosperms, in particular, appear to have employed a range of morphologies and strategies as diverse as those of angiosperms today. The apparently small contribution of climbers to Mesozoic ecosystems, in contrast, may be a result of relatively few detailed morphological and anatomical studies capable of identifying fossil lianas, as well as unusually inhospitable conditions for growth and fossilization. The importance of climbers in ancient ecosystems is underlined to encourage greater recognition of life form diversity in the past.