We study the relationship between vocabulary size and text length in a corpus of 75 literary works in English, authored by six writers, distinguishing between the contributions of three grammatical classes (or ``tags,'' namely, nouns, verbs, and others), and analyze the progressive appearance of new words of each tag along each individual text. We find that, as prescribed by Heaps' law, vocabulary sizes and text lengths follow a well-defined power-law relation. Meanwhile, the appearance of...
Domestic and wild native herbivores combined are still overgrazing Patagonia rangelands: A response to Marino et al. (2019)Gabriel Esteban Oliva, Paula Paredes, Daniela Ferrante, Carla Cepeda & Jorge Rabinovich
1. Oliva et al. (2019) based upon primary productivity estimates concluded that, after long periods of overgrazing, Patagonia´s domestic stocks adjusted to regional-scale herbivore carrying capacity at the end of last century. Guanaco populations, a native camelid, increased thereafter driving combined grazing pressures once again over carrying capacity in some areas. 2. Marino, Rodriguez and Schroeder (2019) argued that domestic grazing is not really at equilibrium because domestic stocks are concentrated in areas that remain...
The reduction of food intake during pregnancy is part of many cultural and religious traditions around the world. The impact of such practices on fetal growth and development are poorly understood. Here, we examined the patterns of diet intake among Maasai pregnant women and assessed their effect on newborn morphometrics. We recruited 141 mother-infant pairs from Ngorongoro Conservation Area (NCA) in Northern Tanzania and quantified dietary intake and changes in maternal diet during pregnancy. We...
The Cretaceous-Paleogene (K/Pg) extinction appears to have been geographically heterogeneous for some organismal groups. Southern Hemisphere K/Pg palynological records have shown lower extinction and faster recovery than in the Northern Hemisphere, but no comparable, well-constrained Southern Hemisphere macrofloras spanning this interval had been available. Here, macrofloral turnover patterns are addressed for the first time in the Southern Hemisphere, using over 3,500 dicot leaves from the latest Cretaceous (Maastrichtian) and the earliest Paleocene (Danian) of Argentine...
Data from: Trait matching and phenological overlap increase the spatio-temporal stability and functionality of plant-pollinator interactionsNatacha P. Chacoff, Diego P. Vázquez & Silvia B. Lomáscolo
Morphology and phenology influence plant-pollinator network structure, but whether they generate more stable pairwise interactions with higher pollination success is unknown. Here we evaluate the importance of morphological trait matching, phenological overlap and specialisation for the spatio-temporal stability (measured as variability) of plant-pollinator interactions and for pollination success, while controlling for species abundance. To this end, we combined a six-year plant-pollinator interaction dataset, with information on species traits, phenologies, specialisation, abundance and pollination success, into...
Data from: How important is it to consider lineage diversification heterogeneity in macroevolutionary studies? lessons from the lizard family LiolaemidaeMelisa Olave, Luciano Avila, Jack Sites & Mariana Morando
Macroevolutionary and biogeographical studies commonly apply multiple models to test state-dependent diversification. These models track the association between states of interest along a phylogeny, although many of them do not consider whether different clades might be evolving under different evolutionary drivers. Yet, they are still commonly applied to empirical studies without careful consideration of possible lineage diversification heterogeneity along the phylogenetic tree. A recent biogeographic study has suggested that orogenic uplift of the southern Andes...
The phenomenon of over-summering in southern non-breeding areas by boreal-breeding birds is particularly prevalent among shorebirds. Despite its frequency, it is understudied compared with most other aspects of shorebird ecology. Our aim was to expand knowledge of this subject through a study of Red Knots Calidris canutus rufa over-summering at a site in Argentina during the austral winter. We measured the proportion of one-year-old and adult over-summerers and evaluated the roles of flight-feather condition and...
Studying how habitat loss affects the tolerance of ecological networks to species extinction (i.e. their robustness) is key for our understanding of the influence of human activities on natural ecosystems. With networks typically occurring as local interaction networks interconnected in space (a meta-network), we may ask how the loss of specific habitat fragments affects the overall robustness of the meta-network. To address this question, for an empirical meta-network of plants, herbivores and natural enemies we...
Raster layers of prioritisation analyses for current and future conditions based on phylogenetic diversity of Neotropical palmsSantiago José Elías Velazco
Aim: Palms are an ecologically and societally important plant group, with high diversity in the Neotropics. Here, we estimated the impacts of future climate change on phylogenetic diversity (PD) of Neotropical palms under varying climatic and dispersal scenarios, assessed the effectiveness of the established network of protected areas (PAs) for conserving palms PD today and in 2070, and identified priority areas for the conservation of palm species and their evolutionary history in the face of...
The riverine barrier hypothesis proposes that large rivers represent geographic barriers to gene flow for terrestrial organisms, leading to population differentiation and ultimately allopatric speciation. Here we asses for the first time if the subtropical Paraná-Paraguay River system in the Del Plata basin, second in size among South American drainages, acts as a barrier to gene flow for birds. We analyzed the degree of mitochondrial and nuclear genomic differentiation in seven species with known subspecies...
Metapopulation dynamics and foraging plasticity in a highly vagile seabird, the southern rockhopper penguinNicolas Lois, Leonardo Campagna, Ulises Balza, Michael Polito, Klemens Pütz, Juliana Vianna, Annick Morgenthaler, Esteban Frere, Ricardo Saenz-Samaniego, Andrea Raya Rey & Bettina Mahler
Population connectivity is driven by individual dispersal potential and modulated by natal philopatry. In seabirds, high vagility facilitates dispersal yet philopatry is also common, with foraging area overlap often correlated with population connectivity. We assess the interplay between these processes by studying past and current connectivity and foraging niche overlap among southern rockhopper penguin colonies of the coast of southern South America using genomic and stable isotope analyses. We found two distinct genetic clusters and...
National Scientific and Technical Research Council11
Bernardino Rivadavia Natural Sciences Museum1
University of Buenos Aires1
University of Washington1
National University of the Littoral1
Catholic University of Health and Allied Sciences1
Museum of Paleontology Egidio Feruglio1
National University of Austral Patagonia1
University of Colorado Denver1