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Extensive interspecific genetic introgression is often reported, and appraising its genomic impact can serve to determine whether it results from selection on specific loci or from demographic processes affecting the whole genome. The three species of hares present in the Iberian Peninsula harbour high frequencies of mitochondrial DNA (mtDNA) from Lepus timidus, an arctic/boreal species now extinct in the region. This could result from the invasive replacement of L. timidus by the temperate species during deglaciation but should then have left traces in the nuclear genome. We typed single nucleotide polymorphisms (SNPs) discovered by sequencing 10 autosomal loci, two X-linked and one Y-linked in species-wide samples of the four taxa. Based on lineage-diagnostic SNPs, we detected no trace of L. timidus sex chromosomes in Iberia. From the frequencies of inferred haplotypes, autosomal introgression into L. granatensis appeared mostly sporadic but always widespread instead of restricted to the north as mtDNA. Autosomal introgression into Iberian L. europaeus, inhabiting the Pyrenean foothills, was hardly detectable, despite quasi-fixation of L. timidus mtDNA. L. castroviejoi, endemic to the Cantabrian Mountains and fixed for L. timidus mtDNA, showed little traces of autosomal introgression. The absence of sex-chromosome introgression presumably resulted from X-linked hybrid male unfitness. The contrasting patterns between the autosomes and mtDNA could reflect general gender asymmetric processes such as frequency-dependent female assortative mating, lower mtDNA migration and higher male dispersal, but adaptive mtDNA introgression cannot be dismissed. Additionally, we document reciprocal introgression between L. europaeus and both L. granatensis in Iberia and L. timidus outside Iberia. [ABSTRACT FROM AUTHOR]

The future of the montado , a human shaped agro-forestry ecosystem of South Western Europe, is questioned due to the observed lack of cork oak health and low natural regeneration. We developed a System Dynamics Modelling approach to predict the long-term sustainability of this agro-forest, by recreating cork-oak population dynamics, management practices and the main environmental and biological constrains associated with this ecosystem. Our results indicate that the leading limitations to cork oak regeneration in montado ecosystems result from the intensity and interaction of land management practices, namely livestock and the use of heavy machinery. The main conclusions indicate that limiting the quantity of livestock up to 0.40 LU.ha −1 , and considering soil ploughing with a minimum periodicity of 5 years, are crucial to maintaining sustainable cork oak populations. This study represents a first step to support strategic options for cork oak montado management by providing projections of long-term population trends under realistic social-ecological change scenarios. [ABSTRACT FROM AUTHOR]