Oliva-Tejera F, Caujapé-Castells J, Navarro-Déniz J, Reyes-Betancort JA, Scholz S, Baccarani-Rosas M, Cabrera-García N
American Journal of Botany 93: 1116–1124 (2006)
We examined data for 11 allozyme loci in 14 populations that represent the distribution of the endangered Lotus kunkelii, the narrowly distributed L. arinagensis (both endemic to Gran Canaria), and the broad-ranging L. lancerottensis (endemic to the easternmost Canary Islands, Fuerteventura and Lanzarote) to explore and construe patterns of genetic variation and use this data to assess the controversial taxonomic status of L. kunkelii relative to L. lancerottensis. While L. kunkelii maintains low levels of variation, presumably as a consequence of prolonged inbreeding due to very low population size and sharp geographic isolation, the other two taxa have much higher indicators of polymorphism than those reported for other oceanic island endemics. Lotus arinagensis has the highest genetic polymorphism and the lowest interpopulation differentiation, presumably because of its considerable antiquity and habitat stability, despite recent fragmentation. The high interpopulation differentiation in L. lancerottensis is attributed to the Atlantic acting as a barrier, reducing gene flow within islands. Evolutionary analysis of theallozyme evidence indicates that L. kunkelii is genetically closer to L. arinagensis than to L. lancerottensis, thereby dispelling the taxonomic uncertainty and supporting L. kunkelii as a distinct species, warranting legal protection in the forthcoming catalog of threatened Canarian species.
Gran Canaria Group 2006
Ediciones del Cabildo de Gran Canaria, La Palmas de Gran Canaria (2006)
The world today is changing more rapidly than at any time in human history. The least predictable and potentially most disruptive alteration of all concerns the Earth’s climate. Climate changes are intimately connected with plants, which harness the energy of the sun through photosynthesis and maintain ecosystems for all life on the planet. The fate of hymanity is therefore inseparable of the fate of plants. Human life is impossible without the ecosystem services provided by plants. In this document, elements of an action plan are designed to prevent plant species extinction and the failure of ecosystem functioning under current and future climate change scenarios
Population genetic differentiation in taxa of Lotus (Fabaceae: Loteae) endemic to the Gran Canarian pine forest
Oliva-Tejera F, Caujapé-Castells J, Naranjo-Suárez J, Navarro-Déniz J, Acebes-Ginovés JR, Bramwell D
Heredity 94: 199-206 (2005)
A survey of allozyme variation at 17 loci in 14 populations representing four taxonomically problematic Gran Canarian pine forest endemic taxa of Lotus (L. genistoides, L. holosericeus, L. spartioides and some taxonomically uncertain populations collected under the designation Lotus sp.) was conducted to examine their diversification and systematic relationships. All groups exhibited high values of genetic variation, although inbreeding was common within populations. Considerable among-population genetic homogeneity was detected, as inferred from low values of GST within each of the groups. The high population sizes of these taxa and a lack of evidence for isolation by distance or genetic bottlenecks indicate that diversity has accumulated over a long period of environmental stability. The association of high genetic distances with low linear distances, and the substantial increase in the values of GST when the taxa considered were merged in different combinations hint at anincipient (yet probably taxonomically insufficient) reproductive isolation. The genetic similarity between L. genistoides, L. holosericeus and L. spartioides, together with the different behaviour of the populations collected under the designation Lotus sp., may have important implications for the restructuring of the taxonomy of this group when the ongoing morphological studies are completed
Sánchez-Doreste JL, Caujapé-Castells J, Reyes-Betancort JA, Scholz S
Plant Systematics and Evolution 262: 139–151 (2006)
Genetic variation at 11 isozyme loci was used to explore the levels and apportionment of genetic variation in the eight known populations of Matthiola bolleana, an endemic Brassicaceae to the Eastern Canarian islands of Fuerteventura and Lanzarote. Within islands, ecosystem antiquity and uniformity, lack of evidence for selection or genetic bottlenecks, the high genetic identities between the populations, and the low values of FST converge tosuggest that the high levels of variation detected have been maintained in a context of prolonged environmental stability through an overall predominance of outbreeding and unrestricted gene flow. Despite the geographical closeness between Fuerteventura and Lanzarote and the long range dispersal features of the propagules of M. bolleana, we detected a striking qualitative genetic differentiation between the two islands. We suggest that wind direction has made seed and pollen flow between Fuerteventura and Lanzarote much less likely than expected, and that the lack of inter-island dispersal has far overriden the influence of stochastic forces and of the reproductive attributes of M. bolleana in shaping the patterns of inter-island genetic differentiation. However, genetic similarity in M. bolleana is within the ranges defined by Canarian taxa for which the extent of genetic differentiation has also been assessed using the values of isozyme genetic identity
Fernández-Palacios O, Pérez de Paz J, Febles R, Caujapé-Castells J
Botánica Macaronésica 26: 19-54 (2006)
We assess the levels and structuring of genetic variation in three populations of the widely distributed Gran Canarian endemic species Parolinia ornata (Brassicaceae: Matthioleae) and we compare their intra-population diversity with two congeneric monotypic species with similar population sizes: P. glabriuscula and P. platypetala. Overall, levels of genetic variation in the three populations of P. ornata are high (with average values of basic polymorphism indicators of Al = 3.8, P = 69.2, He=0.301) and manifest a generalised lack of Hardy-Weinberg equilibrium and homozygote excess. Cogent with the high value of genetic identity estimated (I = 0.959), the inter-population component of genetic variation was low (GST= 0.067), indicating a considerable genetic cohesion among these populations. Qualitatively, we detected a high number of exclusive alleles in the three populations, but especially in Barranco de Tirajana, thereby suggesting a possibly higher antiquity of this population. These results indicate that, in Parolinia, lineage ascription is more important to explain the levels of diversity attained by a species than its geographic distribution or its population size