Bergero R.,University of Edinburgh |
Qiu S.,University of Edinburgh |
Forrest A.,University of Edinburgh |
Forrest A.,Center for Middle Eastern Plants |
And 2 more authors.
Genetics | Year: 2013
There are two very interesting aspects to the evolution of sex chromosomes: what happens after recombination between these chromosome pairs stops and why suppressed recombination evolves. The former question has been intensively studied in a diversity of organisms, but the latter has been studied largely theoretically. To obtain empirical data, we used codominant genic markers in genetic mapping of the dioecious plant Silene latifolia, together with comparative mapping of S. latifolia sex-linked genes in S. vulgaris (a related hermaphrodite species without sex chromosomes). We mapped 29 S. latifolia fully sex-linked genes (including 21 newly discovered from transcriptome sequencing), plus 6 genes in a recombining pseudo-autosomal region (PAR) whose genetic map length is ~25 cM in both male and female meiosis, suggesting that the PAR may contain many genes. Our comparative mapping shows that most fully sex-linked genes in S. latifolia are located on a single S. vulgaris linkage group and were probably inherited from a single autosome of an ancestor. However, unexpectedly, our maps suggest that the S. latifolia PAR region expanded through translocation events. Some genes in these regions still recombine in S. latifolia, but some genes from both addition events are now fully sex-linked. Recombination suppression is therefore still ongoing in S. latifolia, and multiple recombination suppression events have occurred in a timescale of few million years, much shorter than the timescale of formation of the most recent evolutionary strata of mammal and bird sex chromosomes. © 2013 by the Genetics Society of America.
Patzelt A.,Oman Botanic Garden |
Harrison T.,BG Group |
Knees S.G.,Center for Middle Eastern Plants |
Al Harthy L.,Oman Botanic Garden
Edinburgh Journal of Botany | Year: 2014
Sixty new or updated records of plant species are reported from the Sultanate of Oman, as a result of field work and herbarium research. Four taxa represent new records for Arabia, 26 are new records for Oman, and 30 represent an extended distribution within Oman. Some previously doubtful records are confirmed. Brief comments are given on the phytogeography and ecology of the taxa. Most new records have been made in mountainous areas, either in southern or northern Oman, mostly in areas that previously were botanically very poorly known or unexplored. © Trustees of the Royal Botanic Garden Edinburgh (2014).
Hall M.,Center for Middle Eastern Plants
Environmental Politics | Year: 2011
Human-centred hierarchies have been identified as one of the fundamental drivers of ecological overshoot, biological extinctions and ecosystem collapse. As a political philosophy that rejects hierarchy, authority and domination, anarchism represents a promising basis for a more environmental culture. Yet historically, anarchism has had an ambiguous relationship with the natural world. Whilst claiming to be 'ecological', social ecologists, anarcho-primitivists and deep ecologists have not addressed the need for non-hierarchical relationships with the non-human world. Influenced by eco-feminism, a more promising eco-anarchism is emerging that identifies non-humans as fellow anarchists and activists, intelligently collaborating in the eco-anarchist defence of the Earth. In order to fully remove the corrupting influence of hierarchy, eco-anarchism needs to properly situate non-humans within heterarchical relationships of kinship, care and respect. Strategies for implementing these relationships are suggested. © 2011 Taylor & Francis.
Van Damme K.,Ghent University |
Banfield L.,Center for Middle Eastern Plants
Zoology in the Middle East | Year: 2011
The Socotra Archipelago (Yemen) is globally recognized for its outstanding biodiversity and endemism, designated on this basis a UNESCO World Heritage Site in 2008. The island underwent long geological and political isolation, ensuring preservation of unique ecosystems until the start of the new millennium. Now, Socotra Island is undergoing rapid development, out of balance with conservation. Major causes for biodiversity loss in other global insular ecosystems such as habitat fragmentation and degradation, pollution, invasive species and the impact of tourism, are becoming pressing issues that deserve close attention. Unsustainable resource use, the loss of traditional land management and illegal trade in biota are worrying phenomena that further increase the pressures on Socotra's ecosystems. We provide the first comprehensive review of potential human impacts on Socotra before the 21 st century, an updated discussion of some of the principal threats to its biodiversity in recent times, discussing local examples within a historical context of known extinction processes on islands, and underline the importance of traditional knowledge in the protection of Socotran ecosystems. © Kasparek Verlag, Heidelberg.
Vargas P.,Real Jardin Botanico RJB CSIC |
Valente L.M.,Imperial College London |
Blanco-Pastor J.L.,Real Jardin Botanico RJB CSIC |
Liberal I.,Real Jardin Botanico RJB CSIC |
And 4 more authors.
Journal of Biogeography | Year: 2014
Aim: The biogeographical congruence hypothesis, that similar spatiotemporal patterns of geographical distribution exist across lineages, is revisited in this study, and biogeographical processes in presumed Madrean-Tethyan plants are investigated by employing phylogenetic analyses. Location: Mediterranean and Californian floristic regions. Methods: The snapdragons (tribe Antirrhineae, Plantaginaceae) are one of the plant groups that best illustrate disjunctions between the New World (14 genera) and the Old World (15 genera). A time-calibrated phylogeny (ndhF sequences) and ancestral-area reconstructions were used to test the hypothesis of biogeographical congruence. We estimated support for sister-group relationships together with the probability of temporal congruence of snapdragons and five additional angiosperm groups using a biogeographical approach based on Bayesian inference, parsimony and maximum-likelihood methods. Results: Synchronous divergences of four phylogenetically independent Mediterranean/Californian lineages within Antirrhineae were inferred for the Miocene. This result constitutes the first example of high biogeographical congruence within the same plant group. Analyses of five additional angiosperm groups previously considered exemplars of Madrean-Tethyan disjunctions revealed a total of 10 Mediterranean/Californian sister-group lineages, mostly with Miocene divergence times. In particular, our contrasting biogeographical analysis favoured a prevalent colonization process post-dating the separation of America and Eurasia (Eocene) for at least eight angiosperm lineages. Main conclusions: Explicit testing of the Madrean-Tethyan hypothesis did not support predominant vicariance for Mediterranean/Californian sister groups as previously proposed. Instead, eight Mediterranean/Californian sister-group lineages displayed a Miocene divergence, including considerable biogeographical congruence within Antirrhineae (four independent lineages) and Cistaceae (two lineages). © 2013 John Wiley & Sons Ltd.