Global distribution patterns provide evidence of niche shift by the introduced African dung beetle Digitonthophagus gazella

The establishment of cattle ranches throughout the world has prompted the release of dung beetles as biological control agents that reduce pasture fouling and control dung-breeding flies. One of these beetles, Digitonthophagus gazella (Fabricius) (Coleoptera: Scarabaeidae), that is native to southeast Africa, has been introduced into the Americas, Australia, and New Zealand. Distribution records for this species have been used to develop climate models of potential future establishment. Recent studies, however, identify D. gazella as a complex of seven species. Taking into account this revision, and the clear identification of the records belonging to the actual D. gazella, we developed environmental models to identify factors that have contributed to the establishment of this species across regions and habitats. We compared the environmental conditions of D. gazella in its native range against those in the regions where the species has or has not established. Our results indicate that D. gazella is still absent in certain parts of Central and South America and parts of Africa where it could potentially establish. We speculate that its distribution in Africa is limited by competitive exclusion. The introduction of D. gazella in America is relatively recent, such that the full extent of its distribution has probably yet to be realized. In Australia and North America, D. gazella is present in regions not predicted according to its native environmental conditions. This discrepancy may reflect a lack of competitive exclusion, phenotypic plasticity, and/or genetic adaptation. Our analyses suggest that the species has the ability to adapt to a wide range of environmental conditions that are extremely different from those in their native region. The species represents a useful case study to indicate that an introduced species may expand its realized niche beyond what is expected based on apparent environmental limits in the species native range

Characteristics of children admitted to hospital with acute SARS-CoV-2 infection in Canada in 2020

Background: Risk factors for severe outcomes of SARS-CoV-2 infection are not well established in children. We sought to describe pediatric hospital admissions associated with SARS-CoV-2 infection in Canada and identify risk factors for more severe disease. Methods: We conducted a national prospective study using the infrastructure of the Canadian Paediatric Surveillance Program (CPSP). Cases involving children who were admitted to hospital with microbiologically confirmed SARS-CoV-2 infection were reported from Apr. 8 to Dec. 31 2020, through weekly online questionnaires distributed to the CPSP network of more than 2800 pediatricians. We categorized hospital admissions as related to COVID-19, incidental, or for social or infection control reasons and determined risk factors for disease severity in hospital. Results: Among 264 hospital admissions involving children with SARS-CoV-2 infection during the 9-month study period, 150 (56.8%) admissions were related to COVID-19 and 100 (37.9%) were incidental infections (admissions for other reasons and found to be positive for SARS-CoV-2 on screening). Infants (37.3%) and adolescents (29.6%) represented most cases. Among hospital admissions related to COVID-19, 52 (34.7%) had critical disease, 42 (28.0%) of whom required any form of respiratory or hemodynamic support, and 59 (39.3%) had at least 1 underlying comorbidity. Children with obesity, chronic neurologic conditions or chronic lung disease other than asthma were more likely to have severe or critical COVID-19. Interpretation: Among children who were admitted to hospital with SARSCoV-2 infection in Canada during the early COVID-19 pandemic period, incidental SARS-CoV-2 infection was common. In children admitted with acute COVID-19, obesity and neurologic and respiratory comorbidities were associated with more severe disease.Medicine, Faculty ofNon UBCPediatrics, Department ofReviewedFacultyResearche

Global distribution patterns provide evidence of niche shift by the introduced African dung beetle Digitonthophagus gazella

The establishment of cattle ranches throughout the world has prompted the release of dung beetles as biological control agents that reduce pasture fouling and control dung‐breeding flies. One of these beetles, Digitonthophagus gazella (Fabricius) (Coleoptera: Scarabaeidae), that is native to southeast Africa, has been introduced into the Americas, Australia, and New Zealand. Distribution records for this species have been used to develop climate models of potential future establishment. Recent studies, however, identify D. gazella as a complex of seven species. Taking into account this revision, and the clear identification of the records belonging to the actual D. gazella, we developed environmental models to identify factors that have contributed to the establishment of this species across regions and habitats. We compared the environmental conditions of D. gazella in its native range against those in the regions where the species has or has not established. Our results indicate that D. gazella is still absent in certain parts of Central and South America and parts of Africa where it could potentially establish. We speculate that its distribution in Africa is limited by competitive exclusion. The introduction of D. gazella in America is relatively recent, such that the full extent of its distribution has probably yet to be realized. In Australia and North America, D. gazella is present in regions not predicted according to its native environmental conditions. This discrepancy may reflect a lack of competitive exclusion, phenotypic plasticity, and/or genetic adaptation. Our analyses suggest that the species has the ability to adapt to a wide range of environmental conditions that are extremely different from those in their native region. The species represents a useful case study to indicate that an introduced species may expand its realized niche beyond what is expected based on apparent environmental limits in the species native range.Appendix S1. Digitonthophagus gazella geographical records included in the analysis.Appendix S2. Explanatory variables deleted in the various phases of the screening analysis and those finally selected. Variance inflation factor (V): variables deleted by having a V value <5 in the geographical background (GB) of the native area of Digitonthophagus gazella. Index (I): variables deleted after applying the instability index to identify those with the highest capacity to discriminate between the environmental conditions in the presence cells against those prevailing in the GB area. F: finally selected variables.The data from New Zealand are courtesy of the Dung Beetle Release Strategy Group (DBRSG) and Landcare Research Manaaki Whenua.A Colciencias Ph.D. scholarship.https://onlinelibrary.wiley.com/journal/157074582021-08-11hj2021Zoology and Entomolog