INVESTIGADORES
SOUTO Cintia Paola
artículos
Título:
Lowland valleys shelter ancient Fitzroya cupressoides in temperate South America
Autor/es:
PREMOLI, A.; R. VERGARA; C. SOUTO; A. LARA & A. NEWTON
Revista:
Journal of The Royal Society of New Zealand
Referencias:
Año: 2003 vol. 33 p. 623 - 631
Resumen:
The location of glacial refugia of tree taxa in Patagonia is determined
primarily using data from the fossil pollen record. These data suggest that cold-tolerant
conifers such as Fitzroya cupressoides probably survived the Last Glacial Maximum in
coastal areas of southern Chile, where vegetation types corresponded to those currently
found at relatively high altitudes in the Chilean Coastal Range. Much of this region is
thought to have been covered by ice. However, the question remains whether F.
cupressoides could have persisted locally in ice-free areas within the Central Depression
of Chile. In this area, the species has been almost eliminated by human activities that
have occurred since the 16th century. Geographic patterns of isozyme variation within
21 populations of F. cupressoides indicated that lowland populations showed high
within-population isozyme variation. In addition, lowland populations were clearly
differentiated genetically from those on the coast or in the Andes. These results strongly
suggest that populations of F. cupressoides persisted in the Central Depression throughout
glacial times. This implies that ice caps in the south-western Andes were probably not
continuous, but, instead, the existence of ice-free areas in lowland valleys allowed the
local survival of cold-temperate woody taxa.