Gran Canaria Fossil Floras
Above - Fossiliferous sedimentary sequence related to the formation of the Pliocene Roque Nublo Volcano, Gran Canaria.
extant flora of Macaronesia is of intense interest to botanists who are
attempting to unravel patterns of inter-island dispersal/colonisation
and/or vicariance and intra-island evolution. Model-based molecular
methods (e.g. molecular phylogenetics and biogeography) are used that
produce hypotheses for real-evolution. Currently biologists rely on
geological phenomena to constrain hypotheses e.g. age of volcanic island
emergence or dates of catastrophic island sterilizing eruptions or
flank collapses. These proxies inadequately determine evolutionary
patterns and rates and are subject to (mis)interpretation.
appear to be the only real corroboration for hypotheses. However, until
recently the Canary Islands volcanic stratigraphy has been considered
unfossiliferous. In this study Cajsa lisa Anderson
and I are trying to document the fossil plants of Gran Canaria
contained in Mio-Pliocene volcanic and sedimentary sequences. We are
hoping to explore for further palaeofloras in optimal targets on
Tenerife, La Palma, La Gomera and other macaronesian islands. Central
questions to be addressed include: Do fossil and extant floras exhibit
the same levels of diversity and endemism? Are the forest ecosystems
(laurisilva (laurel forest) and Pinus canariensis cloud forests)), which
had much broader Mediterranean/NW. African distributions in the
Neogene, Miocene relicts? Is there a fossil record of the evolution of
features that make many Macaronesian plants distinctive from their
continental relatives such as woody and/or sclerophyllous habits?
The notion that Gran Canaria lacks fossil has been overturned by our discovery of numerous fossil horizons (Anderson and Channing 2007 abstract - poster, 2008 abstract - poster).
Our research also challenges the assumption that violent volcanism on
Gran Canaria c. 3.5 million years ago sterilized the island.
Pliocene fern fossil, the first recorded from Gran Canaria.
Cajsa wishing she had a ladder to investigate the tree preserved as an external mould in the cliff above her head.