Ciencia habilitada por datos de especímenes
Quillfeldt, P., Y. Bedolla-Guzmán, M. M. Libertelli, Y. Cherel, M. Massaro, and P. Bustamante. 2023. Mercury in Ten Storm-Petrel Populations from the Antarctic to the Subtropics. Archives of Environmental Contamination and Toxicology. https://doi.org/10.1007/s00244-023-01011-3
The oceans become increasingly contaminated as a result of global industrial production and consumer behaviour, and this affects wildlife in areas far removed from sources of pollution. Migratory seabirds such as storm-petrels may forage in areas with different contaminant levels throughout the annual cycle and may show a carry-over of mercury from the winter quarters to the breeding sites. In this study, we compared mercury levels among seven species of storm-petrels breeding on the Antarctic South Shetlands and subantarctic Kerguelen Islands, in temperate waters of the Chatham Islands, New Zealand, and in temperate waters of the Pacific off Mexico. We tested for differences in the level of contamination associated with breeding and inter-breeding distribution and trophic position. We collected inert body feathers and metabolically active blood samples in ten colonies, reflecting long-term (feathers) and short-term (blood) exposures during different periods ranging from early non-breeding (moult) to late breeding. Feathers represent mercury accumulated over the annual cycle between two successive moults. Mercury concentrations in feathers ranged over more than an order of magnitude among species, being lowest in subantarctic Grey-backed Storm-petrels (0.5 μg g −1 dw) and highest in subtropical Leach’s Storm-petrels (7.6 μg g −1 dw, i.e. posing a moderate toxicological risk). Among Antarctic Storm-petrels, Black-bellied Storm-petrels had threefold higher values than Wilson’s Storm-petrels, and in both species, birds from the South Shetlands (Antarctica) had threefold higher values than birds from Kerguelen (subantarctic Indian Ocean). Blood represents mercury taken up over several weeks, and showed similar trends, being lowest in Grey-backed Storm-petrels from Kerguelen (0.5 μg g −1 dw) and highest in Leach’s Storm-petrels (3.6 μg g −1 dw). Among Antarctic storm-petrels, species differences in the blood samples were similar to those in feathers, but site differences were less consistent. Over the breeding season, mercury decreased in blood samples of Antarctic Wilson’s Storm-petrels, but did not change in Wilson’s Storm-petrels from Kerguelen or in Antarctic Black-bellied Storm-petrels. In summary, we found that mercury concentrations in storm-petrels varied due to the distribution of species and differences in prey choice. Depending on prey choices, Antarctic storm-petrels can have similar mercury concentrations as temperate species. The lowest contamination was observed in subantarctic species and populations. The study shows how seabirds, which accumulate dietary pollutants in their tissues in the breeding and non-breeding seasons, can be used to survey marine pollution. Storm-petrels with their wide distributions and relatively low trophic levels may be especially useful, but more detailed knowledge on their prey choice and distributions is needed.
Benson, C. W., M. R. Sheltra, P. J. Maughan, E. N. Jellen, M. D. Robbins, B. S. Bushman, E. L. Patterson, et al. 2023. Homoeologous evolution of the allotetraploid genome of Poa annua L. BMC Genomics 24. https://doi.org/10.1186/s12864-023-09456-5
Background Poa annua (annual bluegrass) is an allotetraploid turfgrass, an agronomically significant weed, and one of the most widely dispersed plant species on earth. Here, we report the chromosome-scale genome assemblies of P. annua’s diploid progenitors, P. infirma and P. supina, and use multi-omic analyses spanning all three species to better understand P. annua’s evolutionary novelty. Results We find that the diploids diverged from their common ancestor 5.5 – 6.3 million years ago and hybridized to form P. annua ≤ 50,000 years ago. The diploid genomes are similar in chromosome structure and most notably distinguished by the divergent evolutionary histories of their transposable elements, leading to a 1.7 × difference in genome size. In allotetraploid P. annua, we find biased movement of retrotransposons from the larger (A) subgenome to the smaller (B) subgenome. We show that P. annua’s B subgenome is preferentially accumulating genes and that its genes are more highly expressed. Whole-genome resequencing of several additional P. annua accessions revealed large-scale chromosomal rearrangements characterized by extensive TE-downsizing and evidence to support the Genome Balance Hypothesis. Conclusions The divergent evolutions of the diploid progenitors played a central role in conferring onto P. annua its remarkable phenotypic plasticity. We find that plant genes (guided by selection and drift) and transposable elements (mostly guided by host immunity) each respond to polyploidy in unique ways and that P. annua uses whole-genome duplication to purge highly parasitized heterochromatic sequences. The findings and genomic resources presented here will enable the development of homoeolog-specific markers for accelerated weed science and turfgrass breeding .
Camacho, F., and G. Peyre. 2022. Red List and Vulnerability Assessment of the Páramo Vascular Flora in the Nevados Natural National Park (Colombia). Tropical Conservation Science 15: 194008292210869. https://doi.org/10.1177/19400829221086958
Background and research aims. The Andean páramo is renowned for its unique biodiversity and sensitivity to environmental threats. However, vulnerability assessments remain scarce, which hinders our capacity to prioritize and apply efficient conservation measures. To this end, we established the Red List of the páramo vascular flora from the Nevados National Natural Park and proposed conservation strategies for its threatened species. Methods. We performed International Union for Conservation of Nature (IUCN) Red List assessments by evaluating Criterion B, including sub-criteria B1–Extent of Occurrence and B2–Area of Occupancy, and using a systematic geographic-ecological approach for conditions a (Location analysis) and b (Continuing decline). We then executed a Conservation Gap Analysis to prioritize species for in- situ and/or ex-situ conservation. Results. Summing our 233 evaluated species with previous assessments, we completed the Red List of 262 páramo species and encountered 3% Threatened (7 VU, one EN), 44% Not Threatened (65 LC, 50 NT), and 53% Data Deficient. We acknowledged Lupinus ruizensis as Endangered and Aequatorium jamesonii, Carex jamesonii, Elaphoglossum cuspidatum, Miconia latifolia, Miconia alborosea, Pentacalia gelida, and Themistoclesia mucronata as Vulnerable. Conclusion. The eight threatened species should be included as target species in the PNN Nevados management plan 2023–2028 and regarded as national conservation priorities. Implications for Conservation. We recommend in-situ conservation for Medium-Priority species A. jamesonii, E. cuspidatum, and T. mucronata with thorough monitoring, paired with sub-population transfers for High-Priority species C. jamesonii. For the endemic L. ruizensis and P. gelida, we suggest combined in-situ/ex-situ strategies taking advantage of national germoplasm collections, like the seed bank of the Bogotá Botanical Garden José Celestino Mutis.
Alban, D. M., E. M. Biersma, J. W. Kadereit, and M. S. Dillenberger. 2021. Colonization of the Southern Hemisphere by Sagina and Colobanthus (Caryophyllaceae). Plant Systematics and Evolution 308. https://doi.org/10.1007/s00606-021-01793-w
Colobanthus (23 species) and Sagina (30–33 species) together are sister to Facchinia. Whereas Facchinia is distributed in western Eurasia, Colobanthus is almost exclusively distributed in the Southern Hemisphere, and Sagina is distributed in both hemispheres with the highest species diversity in wes…
Mairal, M., S. L. Chown, J. Shaw, D. Chala, J. H. Chau, C. Hui, J. M. Kalwij, et al. 2021. Human activity strongly influences genetic dynamics of the most widespread invasive plant in the sub‐Antarctic. Molecular Ecology 31: 1649–1665. https://doi.org/10.1111/mec.16045
The link between the successful establishment of alien species and propagule pressure is well-documented. Less known is how humans influence the post-introduction dynamics of invasive alien populations. The latter requires studying parallel invasions by the same species in habitats that are differen…
Saldaña‐López, A., M. Vilà, F. Lloret, J. Manuel Herrera, and P. González‐Moreno. 2021. Assembly of species’ climatic niches of coastal communities does not shift after invasion Z. Botta‐Dukát [ed.],. Journal of Vegetation Science 32. https://doi.org/10.1111/jvs.12989
Question: Do invasions by invasive plant species with contrasting trait profiles (Arctotheca calendula, Carpobrotus spp., Conyza bonariensis, and Opuntia dillenii) change the climatic niche of coastal plant communities? Location: Atlantic coastal habitats in Huelva (Spain). Methods: We identifi…
Cooper, N., A. L. Bond, J. L. Davis, R. Portela Miguez, L. Tomsett, and K. M. Helgen. 2019. Sex biases in bird and mammal natural history collections. Proceedings of the Royal Society B: Biological Sciences 286: 20192025. https://doi.org/10.1098/rspb.2019.2025
Natural history specimens are widely used across ecology, evolutionary biology and conservation. Although biological sex may influence all of these areas, it is often overlooked in large-scale studies using museum specimens. If collections are biased towards one sex, studies may not be representativ…
Brightly, W. H., S. E. Hartley, C. P. Osborne, K. J. Simpson, and C. A. E. Strömberg. 2020. High silicon concentrations in grasses are linked to environmental conditions and not associated with C 4 photosynthesis. Global Change Biology 26: 7128–7143. https://doi.org/10.1111/gcb.15343
The uptake and deposition of silicon (Si) as silica phytoliths is common among land plants and is associated with a variety of functions. Among these, herbivore defense has received significant attention, particularly with regards to grasses and grasslands. Grasses are well known for their high sili…
Li, K., J. Wang, L. Qiao, R. Zheng, Y. Ma, Y. Chen, X. Hou, et al. 2020. Diversity of Reproductive Phenology Among Subtropical Grasses Is Constrained by Evolution and Climatic Niche. Frontiers in Ecology and Evolution 8. https://doi.org/10.3389/fevo.2020.00181
Reproductive phenology is sensitive to climatic changes and is associated with species functional types, distribution ranges, and their corresponding climatic niches. Phylogenetic niche conservatism in reproductive phenology also constrains its diversity and the distribution of species. Therefore, w…
Lindberg, C. L., H. M. Hanslin, M. Schubert, T. Marcussen, B. Trevaskis, J. C. Preston, and S. Fjellheim. 2020. Increased above‐ground resource allocation is a likely precursor for independent evolutionary origins of annuality in the Pooideae grass subfamily. New Phytologist 228: 318–329. https://doi.org/10.1111/nph.16666
Semelparous annual plants flower a single time during their one‐year life cycle, investing much of their energy into rapid reproduction. In contrast, iteroparous perennial plants flower multiple times over several years, and partition their resources between reproduction and persistence. To which ex…