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- Farmed and wild macroalgae as a safe source of macro and trace elementsPublication . Chainho, Tomás; Cereja, Rui; Pereira, Alícia; Marques, Vera; Silva, João C.; Pessanha, Sofia; Reis Costa, Pedro; Marques, AntónioThe increasing popularity of macroalgae products highlights their potential as a safe source of essential macro and microelements for consumers. This study characterized wild and farmed macroalgae elemental composition and assessed the presence of biotoxins to identify potential health risks. Wild and farmed macroalgae samples were collected throughout 2024–2025, from three aquaculture production sites along the Portuguese coast (Ria de Aveiro, Matosinhos, and Olhão). Samples were freeze-dried, compressed and using a microXRF spectrometer, elemental composition was assessed. Macroalgae species factor was the strongest driver of elemental composition, explaining over 80% variation in macro and trace elements. Origin did not showcase statistical significance for elemental composition. Seasonal differences, though relatively small in extent, significantly impacted redox-sensitive elements in macroalgae, namely copper and manganese. All elements stayed below 30% of the recommended dietary recommendations, except iron (ranging from 0.5% to 111.8% of UL%) and Mn (ranging from 0.1% to 101% of UL%). All samples revealed the absence of regulated marine toxins. Only traces of the non-regulated cyclic-imine toxin SPX1 were detected in samples of Fucus vesiculosus. All quantified elements do not represent any risk for human health, strengthening the safety of macroalgae from the Portuguese coast.
- Mia Couto: os sonhos de Kindzu, em terra sonâmbulaPublication . Pereira, José Paulo de Lemos e Melo CruzTerra Sonâmbula foi o romance inaugural de Mia Couto. O que dele aqui suscita o nosso interesse diz respeito quer à conceção de viagem, quer às noções de escrita e de sonho que, na história de Kindzu, se cruzam. Em que consiste aí o sonho? Como é que ele arrasta, consigo, a noção de escrita, na poética de Mia Couto? Com efeito, quando interpelado, a certa altura, pelo xipoco1 de Taímo – o fantasma de seu falecido e desconsolado pai...
- Genomic footprints of selfing, introduction history, and long-distance dispersal in an invasive alien plantPublication . Sánchez-García, Raúl; Green, Andy J; Ortiz, María A; García, Cristina; Hortas, Francisco; Reynolds, Chevonne; Rowntree, Jennifer; Serrao, Ester A.; Tomasson, Lina; Tremetsberger, Karin; Leeuwen, Casper H A van; Ortego, Joaquín; Sangeet LamichhaneyBiological invasions are natural experiments for studying the evolutionary and ecological processes underlying colonization success and range expansion. Using genome-wide data—generated via genotyping-by-sequencing (GBS) from 30 populations spanning Europe and South Africa—we investigated the colonization history and successful spread of the invasive buttonweed Cotula coronopifolia, an annual plant introduced into Europe from South Africa about 300 years ago. Our analyses identified three major lineages in Europe distributed across the continent, often co-occurring without evidence of admixture. Phylogenomic dating revealed that these lineages diverged > 2,000 years ago—well before the earliest European records—suggesting divergence within the native range and either multiple introductions or a single introduction with multiple lineages. Mating-system inference shows that reproduction occurs primarily via self-fertilization (∼70% on average), although outcrossing predominates in some populations, revealing a facultative mating system. This high selfing rate has led to extremely low heterozygosity in most populations and a strong genetic structure. Genetic clustering also revealed admixed individuals resulting from rare inter-lineage outcrossing; comparisons of empirical and simulated data indicate that increased diversity after sporadic admixture events decays rapidly under subsequent selfing. Both the introduction history and long-distance dispersal facilitated by waterbirds likely explain the scattered distribution of lineages across Europe. Altogether, these results illustrate Baker’s “ideal weed” concept, highlighting the role of a flexible mating system in providing reproductive assurance during colonization and showing how predominant selfing can shape the genomic landscape of an invasive species.