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Human impact has contributed to the decline of the Eurasion lynx

Disentangling the contribution of long?term evolutionary processes and recent anthropogenic impacts to current genetic patterns of wildlife species is key to assessing genetic risks and designing conservation strategies. Eighty whole nuclear genomes and 96 mitogenomes from populations of the Eurasian lynx covering a range of conservation statuses, climatic zones and subspecies across Eurasia were used to infer the demographic history, reconstruct genetic patterns, and discuss the influence of long?term isolation and more recent human?driven changes. Results show that Eurasian lynx populations shared a common history until 100,000 years ago, when Asian and European populations started to diverge and both entered a period of continuous and widespread decline, with western populations, except Kirov (Russia), maintaining lower effective sizes than eastern populations. Population declines and increased isolation in more recent times probably drove the genetic differentiation between geographically and ecologically close westernmost European populations. By contrast, and despite the wide range of habitats covered, populations are quite homogeneous genetically across the Asian range, showing a pattern of isolation by distance and providing little genetic support for the several proposed subspecies. Mitogenomic and nuclear divergences and population declines starting during the Late Pleistocene can be mostly attributed to climatic fluctuations and early human influence, but the widespread and sustained decline since the Holocene is more probably the consequence of anthropogenic impacts which intensified in recent centuries, especially in western Europe. Genetic erosion in isolated European populations and lack of evidence for long?term isolation argue for the restoration of lost population connectivity between European and Asian poulations. informacion[at]ebd.csic.es: Lucena-Perez et al (2020). Genomic patterns in the widespread Eurasian lynx shaped by Late Quaternary climatic fluctuations and anthropogenic impacts. MOL ECOL 29(4) DOI 10.1111/mec.15366


https://onlinelibrary.wiley.com/doi/full/10.1111/mec.15366
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Avian malaria parasites reduce the survival of mosquitoes

Avian malaria parasites reduce the survival of mosquitoes

Plasmodium transmission success depends upon the trade-off between the use of host resources to favour parasite reproduction and the negative effects on host health, which can be mediated by infection intensity. Despite its potential influence on parasite dynamics, the effects of infection intensity on both, birds and vectors, and on Plasmodium transmission success are still poorly understood. Here, the Plasmodium load in naturally infected wild house sparrows was experimentally reduced with the antimalarial primaquine to assess the effects of intensity of infection in the vertebrate hosts on Plasmodium transmission to and by mosquitoes. Survival of Culex pipiens mosquitoes was monitored throughout the development of the parasite and the infection status of the mosquitoes by analysing the head-thorax and saliva at 13 days post-exposure to birds. The proportion of mosquitoes infected by Plasmodium and the presence of Plasmodium in saliva were not associated with the medication treatment of birds. However, the experimental treatment affected vector survival with mosquitoes fed on medicated birds showing a higher survival rate than those fed on control individuals. These results provide strong experimental evidence of the impact of parasite load of vertebrate hosts on the survival probability of malaria vectors. Like humans, wild birds can be infected with malaria, although the malaria parasites that affect birds are different and can not be transmitted to humans. Avian malaria parasites require mosquitoes to be transmitted effectively between an infected bird and a new host, but the results of this study indicate that these parasites involve a cost on the survival of the insects. informacion[at]ebd.csic.es: Gutiérrez-López et al (2019) Experimental reduction of host Plasmodium infection load affects mosquito survival. Scientific Reports 9(1): 8782 https://doi.org/10.1038/s41598-019-45143-w


https://www.nature.com/articles/s41598-019-45143-w