Abstract
Nowadays, most animal species can be identified genetically by sequencing a fragment of the mitochondrial barcoding gene COI. However, for some species, this method is not applicable due to a more complex genetic make-up, often due to hybridisation.
One of these exceptions are the green frogs (pool frog – Pelophylax lessonae, edible frog – P. kl. esculentus and marsh frog – P. ridibundus). This group of frogs has an especially complex genetic composition due to hemiclonal hybridisation and polyploidisation.
To establish a genetic monitoring tool-kit for green frogs in Luxembourg, we will first apply ddRAD sequencing to a wide range of populations from the whole country. This high-throughput sequencing based method will be used to generate hundreds of genome-wide genetic markers. The resulting dataset will allow to identify individuals on species level and to assess their ploidy. Furthermore, it will enable an estimation of the genetic diversity of the two common species in Luxembourg, the pool frog and the edible frog.
In a second step of the project, these genetic data will be used to establish genetic markers for standard genetic monitoring in Luxembourg and to develop recommendation guidelines for their application.

Project status
Project granted by the Ministry of Sustainable Development and Infrastructure, Luxembourg. Duration: one year (15.04.2018 – 14.04.2019).
Host institution: Fondation faune-flore @ Centre de recherche scientifique, Musée national d’histoire naturelle.
Contact
Hannah Weigand
Musée national d’histoire naturelle
Centre de recherche scientifique
Zoologie des vertébrés
24, rue Münster
L-2160 Luxembourg
phone: (+352) 462240 212
hannah.weigand@mnhn.lu
Publications
- WEIGAND H. & Leese F. (2018) Detecting signatures of positive selection in non-model species using genomic data. Zoological Journal of the Linnean Society.
- WEIGAND H., Weiss M., Cai H., Li Y., Yu L., Zhang C., Leese F. (2018) Fishing in troubled waters: Revealing genomic signatures of local adaptation in response to freshwater pollutants in two macroinvertebrates. Science of the total environment 633:875-891.
- Weiss M., WEIGAND H., Weigand A.M., Leese F. (2018) Genome-wide SNP data reveal cryptic species
within cryptic freshwater snail species – The case of the Ancylus fluviatilis species complex. Ecology
and Evolution 8:1063-1072. - Steinbach P., Heddergott M., WEIGAND H., Weigand A.M., Wilwert E., Stubbe M., Helm B., Campbell R.E., Stubbe A., Frantz A.C. (2018) Rare migrants suffice to maintain high genetic diversity in an introduced island population of roe deer (Capreolus capreolus): evidence from molecular data and simulations. Mammalian Biology 88:64-71.
- WEIGAND H., Weiss M., Cai H., Li Y., Yu L., Zhang C., Leese, F (2017) Deciphering the origin of mito-nuclear discordance in two sibling caddisfly species. Molecular Ecology 26:5705-5715.
- Vendrami D.L.J., Telesca L., WEIGAND H., Weiss M., Fawcett K., Lehman K., Clark M.S., Leese F., McMinn C., Moore H., Hoffman J.I. (2017) RAD sequencing resolves fine-scale population structure in a benthic invertebrate: implications for understanding phenotypic plasticity. Royal Society open science 4:160548.
- SCHWEYEN H., Rozenberg A., Leese F. (2014) Detection and removal of PCR duplicates in population genomic ddRAD studies by yddition of a degenerate base region (DBR) in sequencing adapters. Biological Bulletin 227:146-160.
- Magwire M.M.*, Fabian D.K.*, SCHWEYEN H.*, Cao C., Longdon B., Bayer F., Jiggins F.M. (2012) Genome-wide association studies reveal a simple genetic basis of resistance to naturally coevolving viruses in Drosophila melanogaster. PLOS Genetics 8:e1003057 (* equally contributing authors).
- Scharsack J.P., SCHWEYEN H., Schmidt A.M., Dittmar J., Reusch T.B.H., Kurtz J. (2012) Population genetic dynamics of three-spined sticklebacks (Gasterosteus aculeatus) in anthropogenic altered habitats. Ecology and Evolution 2:1122-1143.

David PORCO
Climate is a key factor determining plant distribution. Predictions of rapid climate change have resulted in a renewed interest in the possible responses of plants to changes in climate, such as migration to other localities, phenotypic plasticity and local adaptation. The aim of this project is to study the possible impact of predicted climate change on the short-lived perennial plant Anthyllis vulneraria along environmental gradients. We will analyze natural populations and their habitats along altitudinal and latitudinal gradients to investigate relationships between population characteristics and environmental conditions. We will also investigate molecular genetic diversity in relation to the same gradients. The variation in a number of quantitative traits and its distribution among spatial scales will be studied in a lowland common garden and compared with that of the variation in neutral genetic markers.
Parasitic nematodes can cause serious diseases and their emergence in new areas can be an issue of major concern for human health, agricultural productivity and biodiversity conservation. Molecular studies of nematode invasions can make a significant contribution to a better understanding of the underlying mechanism of the emergence, spread and persistence of the parasites. Also, they will clarify the evolutionary potential of the invaders in their new range and help with the elaboration of adequate management strategies against helminthic disease. The raccoon roundworm (Baylisascaris procyonis) is a common gastrointestinal parasite of the raccoon (Procyon lotor), that is emerging as an important helminthic zoonoses that mainly affects young children. Translocations of raccoons have increased the global geographic range of its roundworm as well. Raccoons are particularly abundant and wide-spread in Germany, where they can occur at high densities in urban areas. Recent genetic work has provided evidence for at least four independent introduction events, which gave rise to genetically differentiated subpopulations in incipient contact of relatively high genetic diversity. The roundworm, however, does not occur in all raccoon populations and might therefore be much less genetically diverse due to reduced propagule pressure. The overall objective of this study is to use population genetic techniques to analyse the genetic diversity and gene flow in the invasive nematode B. procyonis to understand the evolutionary potential of the parasite and allow the implementation of successful control programmes. We aim in particular to establish how frequently the parasite was introduced into Western Europe, to estimate the geographic origin of the introduced parasites, to examine the changes in genetic diversity during the invasion process and to the landscape genetic structure of the raccoon and its roundworm in parallel.
The biological diversity of montane regions may be threatened by predicted climate change. Low mountain species frequently cannot respond to climate change by migrating upward, but only by plasticity or genetic adaptation. Predicted climate change will not only result in changed environmental conditions, but also affect biotic interactions. The aim of this project is to study the possible impact of climate change on the interactions of the threatened plant species Arnica montana with both generalist herbivores and a specialised parasite, the seed fly Tephritis arnicae. We will investigate the impact of herbivory and parasitism on the model species A. montana along an altitudinal gradient, investigate defenses against herbivores using metabolomic profiles, and experimentally study how plant-animal interactions would be affected under predicted climatic change. Population sizes of generalist herbivores are foreseen to increase in upland regions which may threaten the survival of mountain populations of plants that may be less defended against herbivores than lowland populations. We will also study genetic variation in metabolomic profiles and herbivore resistance among and within populations and its importance for adaptation to changed conditions. The population biology of A. montana is currently studied in a PhD project (AFR FNR Grant) hosted by the MNHNL. The proposed PhD project will take advantage of the knowledge about the population biology and quantitative genetics of A. montana obtained in this study and use two common garden experiments already set up at high and low altitudes. The expected results of the project will contribute to a better understanding of the genetic and metabolomic diversity of rare and endangered species and its importance under the scenario of projected climate change. The outcomes will also have implications for the conservation and management of biodiversity and allow a better understanding of the role of systems biology in biodiversity conservation.



