Climate-induced range shifts and possible hybridisation consequences in insects.

Many ectotherms have altered their geographic ranges in response to rising global temperatures. Current range shifts will likely increase the sympatry and hybridisation between recently diverged species. Here we predict future sympatric distributions and risk of hybridisation in seven Mediterranean ischnurid damselfly species (I. elegans, I. fountaineae, I. genei, I. graellsii, I. pumilio, I. saharensis and I. senegalensis). We used a maximum entropy modelling technique to predict future potential distribution under four different Global Circulation Models and a realistic emissions scenario of climate change. We carried out a comprehensive data compilation of reproductive isolation (habitat, temporal, sexual, mechanical and gametic) between the seven studied species. Combining the potential distribution and data of reproductive isolation at different instances (habitat, temporal, sexual, mechanical and gametic), we infer the risk of hybridisation in these insects. Our findings showed that all but I. graellsii will decrease in distributional extent and all species except I. senegalensis are predicted to have northern range shifts. Models of potential distribution predicted an increase of the likely overlapping ranges for 12 species combinations, out of a total of 42 combinations, 10 of which currently overlap. Moreover, the lack of complete reproductive isolation and the patterns of hybridisation detected between closely related ischnurids, could lead to local extinctions of native species if the hybrids or the introgressed colonising species become more successful

Suitability map for current climatic conditions and unique presences used to generate the models of the seven Mediterranean <i>Ischnura</i> species treated in this study: <i>I. elegans</i> (A); <i>I. fountaineae</i> (B); <i>I. genei</i> (C); <i>I. graellsii</i> (D); <i>I. pumilio</i> (E); <i>I. saharensis</i> (F); <i>I. senegalensis</i> (G).

<p>Suitability increases from dark blue (0) to green (0.5) to red (1).</p

Distribution map of the seven Mediterranean <i>Ischnura</i> species treated in this study (<i>I. elegans</i>, <i>I. fountaineae, I. genei</i>, <i>I. graellsii, I. pumilio, I. saharensis</i> and <i>I. senegalensis</i>).

<p>Distribution map of the seven Mediterranean <i>Ischnura</i> species treated in this study (<i>I. elegans</i>, <i>I. fountaineae, I. genei</i>, <i>I. graellsii, I. pumilio, I. saharensis</i> and <i>I. senegalensis</i>).</p

One Health Interactions of Chagas Disease Vectors, Canid Hosts, and Human Residents along the Texas-Mexico Border.

BACKGROUND:Chagas disease (Trypanosoma cruzi infection) is the leading cause of non-ischemic dilated cardiomyopathy in Latin America. Texas, particularly the southern region, has compounding factors that could contribute to T. cruzi transmission; however, epidemiologic studies are lacking. The aim of this study was to ascertain the prevalence of T. cruzi in three different mammalian species (coyotes, stray domestic dogs, and humans) and vectors (Triatoma species) to understand the burden of Chagas disease among sylvatic, peridomestic, and domestic cycles. METHODOLOGY/PRINCIPAL FINDINGS:To determine prevalence of infection, we tested sera from coyotes, stray domestic dogs housed in public shelters, and residents participating in related research studies and found 8%, 3.8%, and 0.36% positive for T. cruzi, respectively. PCR was used to determine the prevalence of T. cruzi DNA in vectors collected in peridomestic locations in the region, with 56.5% testing positive for the parasite, further confirming risk of transmission in the region. CONCLUSIONS/SIGNIFICANCE:Our findings contribute to the growing body of evidence for autochthonous Chagas disease transmission in south Texas. Considering this region has a population of 1.3 million, and up to 30% of T. cruzi infected individuals developing severe cardiac disease, it is imperative that we identify high risk groups for surveillance and treatment purposes

<i>Trypanosoma Cruzi</i> (Chagas Disease) Positive Samples By Species And Geographic Origin.

<p><i>Trypanosoma Cruzi</i> (Chagas Disease) Positive Samples By Species And Geographic Origin.</p

<i>Trypanosoma Cruzi</i> (Chagas Disease) Prevalence In Coyotes, Shelter Dogs, Human Residents, And Vectors Of South Texas.

<p><i>Trypanosoma Cruzi</i> (Chagas Disease) Prevalence In Coyotes, Shelter Dogs, Human Residents, And Vectors Of South Texas.</p