Se presentan los resultados del recorrido de superficie realizado en la comunidad de Santo Domingo Tonaltepec en la Mixteca Alta de Oaxaca, en el que se identificaron y registraron 43 nuevos sitios arqueológicos datados a las fases Ramos (alrededor de los 300 aC hasta los 250 dC), Las Flores (aproximadamente 250-900 dC) y Natividad (aproximadamente 900-1521 dC). Estos nuevos sitios se contextualizan en el ámbito regional al relacionarlos con los sitios urbanos identificados para cada una de estas fases en los valles adyacentes de Coixtlahuaca, Nochixtlán, Tamazulapan y Teposcolula. Basados en estos datos, consideramos que Tonaltepec se encontró relativamente aislado y fuera del control de los sitios urbanos tempranos durante Ramos; que se transformó en un asentamiento fronterizo entre las entidades políticas durante la fase Las Flores; y que aprovechó los beneficios de localizarse sobre la ruta de comunicación entre importantes reinos mixtecos durante Natividad. La localización de Tonaltepec, relativamente lejos de los principales valles, pero a la vez entre ellos, le otorgó ventajas que supo aprovechar a través de la historia de desarrollo político de la región.

The coronavirus disease 2019 (COVID-19) outbreak may have affected the mental health of patients at high risk of suicide. In this study we explored the wish to die and other suicide risk factors using smartphone-based ecological momentary assessment (EMA) in patients with a history of suicidal thoughts and behaviour. Contrary to our expectations we found a decrease in the wish to die during lockdown. This is consistent with previous studies showing that suicide rates decrease during periods of social emergency. Smartphone-based EMA can allow us to remotely assess patients and overcome the physical barriers imposed by lockdown.

We present the first report of Amblycerus dispar (Sharp) attacking stored almonds [Prunus dulcis (Mill.) D. A. Webb] in Argentina. A summarized diagnosis, illustrations, and photographs of the adult and mature larva are provided to facilitate identification. We performed species distribution models for A. dispar and its main host plant Geoffroea decorticans (Gillies ex Hook. & Arn.) Burkart. We include A. dispar into a previous morphological character matrix and conduct a phylogenetic analysis to infer its phylogenetic position. The evolution of host plant associations of the genus Amblycerus is herein re-analyzed. A. dispar and its main host shows high suitability areas especially in central-west Argentina and Chile, whereas for the USA, high suitability areas were found for the south-western which include the area of almond production in this country. Although the presence of A. dispar in the USA region is very unlikely, we recommend some awareness as other bruchines are present in the area. Although A. dispar is unlikely to become an economically important risk, monitoring for early detection is recommended to avoid productivity loss, especially when the native host is nearby cultivated areas. A. dispar is hypothesized to be the sister species of A. schwarzi Kingsolver. The colonization of a Rosaceae species is a novelty for this genus, being host shifts known as an important factor affecting both natural and agricultural systems.

Food partitioning among coexisting species is often considered advantageous to minimize niche overlap and avoid inter-specific competition. Congeneric fish species such as the mullets Mugil curema and Mugil liza, which co-occur across marine and estuarine habitats, are good models to evaluate resource use and niche overlap or partitioning. We used stomach contents (SCA) and stable isotope analysis (SIA) to assess potential trophic shifts and changes in niche overlap associated with the mullets transitioning from marine to estuarine habitats. SIA included different fractions of organic matter in suspension and in the sediment to estimate the contribution of micro, nano and pico-organisms to the mullets’ diets. We hypothesized higher resource partitioning in the less resource-diverse system (marine surf-zone) than in the more diverse one (estuary). SCA showed diet differences between M. curema and M. liza according to the habitat. They showed distinct diets in the marine area (P < 0.001), but similar diets in the estuary (P = 0.226). A lower niche breadth was observed for both species in the marine area (M. curema = 0.03, M. liza = 0.06) compared with the estuary (M. curema = 0.14, M. liza = 0.16). Isotopic niches of both species were higher in the estuary (64.7%) compared with the marine area (0.7%). These findings corroborated our hypothesis of higher food partitioning in the marine surf-zone. We also demonstrated using SIA the shift from planktonic to benthic feeding following the recruitment of the mullets from the surf-zone into the estuary.

The El Salt site (Alcoi, Alicante, Spain) is one of the latest Neanderthal sites in the south-eastern Iberian Peninsula. The disappearance of this human group is controversial and needs detailed studies from different research areas. Taphonomy is essential to establish how representative is a fossil assemblage of the past living organisms that produced it and to interpret the formation process of the fossil site. In the case of El Salt, we have analyzed the micromammal assemblages of Units X and V, which contain fossils of Neanderthals and/or evidence of their activity. In contrast with previous identifications of the little owl (Athene noctua), our detailed taphonomic study shown here allows us to conclude that the main predator involved in the production of the micromammal assemblages was the European eagle owl (Bubo bubo). This is an opportunistic predator whose feeding preferences and behavior reflect the abundance of local micromammalian species, which can therefore provide a representation of past ecosystems near El Salt. The taphonomic information provided by this study also indicates the absence of transport and reworking processes, and reinforces previous paleoecological interpretations, suggesting an increase of aridity at the top of El Salt sequence that coincided with the local disappearance of Neanderthals.

Elasmobranchs in the Gulf of California have been found with malformations, probably originated during embryonic development or caused by environmental anomalies and pollution associated with intense mining activity in the region. Clasper malformations are reported for the first time in two specimens of Pseudobatos buthi, a species recently described from the Gulf of California. The function of the claspers was not affected by the size difference, because specimens presented the distinctive characteristics of an adult individual. The reproductive system did not show any malformation, with symmetrical testes. Histological analysis of the testes revealed a normal spermatogenic development. To elucidate the causes and to detect a possible effect of the morphological malformations due to high levels of heavy metals, trace concentration values (cadmium, copper, iron, manganese, silver, lead and zinc) were determined in muscle and liver. Cadmium and lead concentrations in the muscle of the two specimens were below the permissible limit for human consumption (<0.05 mg kg−1); however, iron and zinc presented high values (0.455, 4.024 mg kg−1 in muscle and 21.931, 3.694 mg kg−1 in liver respectively). Mining activity and heavy metal pollution in the sampling area may have caused the malformations, which might be attributed to the high values of iron and zinc discovered in the muscle and liver.