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Honeybee colonies have increased exponentially in the Mediterranean Basin

Evidence for pollinator declines largely originates from mid-latitude regions in North America and Europe. Geographical heterogeneity in pollinator trends combined with geographical biases in pollinator studies can produce distorted extrapolations and limit understanding of pollinator responses to environmental changes. In contrast with the declines experienced in some well-investigated European and North American regions, honeybees seem to have increased recently in some areas of the Mediterranean Basin. The Mediterranean Basin is home to approximately 3300 wild bee species, or approximately 87% of those occurring in the whole western Palaearctic region. Because honeybees can have negative impacts on wild bees, it was hypothesized that a biome-wide alteration in bee pollinator assemblages may be underway in the Mediterranean Basin involving a reduction in the relative number of wild bees. This hypothesis was tested using published quantitative data on bee pollinators of wild and cultivated plants from studies conducted between 1963 and 2017 in 13 countries from the European, African and Asian shores of the Mediterranean Sea. The density of honeybee colonies increased exponentially and wild bees were gradually replaced by honeybees in flowers of wild and cultivated plants. The proportion of wild bees at flowers was four times greater than that of honeybees at the beginning of the period, the proportions of both groups becoming roughly similar 50 years later. The Mediterranean Basin is a world biodiversity hotspot for wild bees and wild bee-pollinated plants, and the ubiquitous rise of honeybees to dominance as pollinators could in the long run undermine the diversity of plants and wild bees in the region. informacion[at]ebd.csic.es: Herrera (2020) Gradual replacement of wild bees by honeybees in flowers of the Mediterranean Basin over the last 50 years. Proc Royal Society B 287(1921). Doi 10.1098/rspb.2019.2657


https://royalsocietypublishing.org/doi/10.1098/rspb.2019.2657
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African and Eurasian golden jackals are distinct species

African and Eurasian golden jackals are distinct species

The golden jackal of Africa (Canis aureus) has long been considered a conspecific of jackals distributed throughout Eurasia. However, two recent reports found that mitochondrial haplotypes of some African golden jackals aligned more closely to gray wolves (Canis lupus) which is surprising given the absence of gray wolves in Africa and the phenotypic divergence between the two species. Moreover, these results imply the existence of a previously unrecognized phylogenetically distinct species despite a long history of taxonomic work on African canids. To test the distinct-species hypothesis and understand the evolutionary history that would account for this puzzling result, extensive genomic data in African and Eurasian golden jackals and gray wolves were analyzed. Results provide consistent and robust evidence that populations of golden jackals from Africa and Eurasia represent distinct monophyletic lineages separated for more than one million years, sufficient to merit formal recognition as different species: C. anthus (African golden wolf) and C. aureus (Eurasian golden jackal). Using morphologic data, a striking morphologic similarity between East African and Eurasian golden jackals was demonstrated, suggesting parallelism, which may have misled taxonomists and likely reflects uniquely intense interspecific competition in the East African carnivore guild. This study shows how ecology can confound taxonomy if interspecific competition constrains size diversification. informacion[at]ebd.csic.es: Koepfli et al (2015) Genome-wide evidence reveals that African and Eurasian Golden jackals are distinct species. Curr Biol 25, 1-8 doi:10.1016/j.cub.2015.06.060


http://www.sciencedirect.com/science/article/pii/S0960982215007873