ZOBODAT - www.zobodat.at Zoologisch-Botanische Datenbank/Zoological-Botanical Database Digitale Literatur/Digital Literature Zeitschrift/Journal: Angewandte Carabidologie Jahr/Year: 2018 Band/Volume: 12 Autor(en)/Author(s): Homburg Katharina Artikel/Article: Effects of climate on diversity patterns in ground beetles – a doctoral thesis combining methods of macroecology, phylogeography and global change biology 17-27 ©Gesellschaft für Angewandte Carabidologie e.V. download www.laufkaefer Effects of climate on diversity patterns in ground beetles – a doctoral thesis combining methods of macroecology, phylogeography and global change biology Katharina HOMBURG1, 2 1 Alfred Toepfer Academy for Nature Conservation, Hof Möhr, D-29640 Schneverdingen, Germany, E-Mail: [email protected] 2 Leuphana University Lüneburg, Animal Ecology, Universitätsallee1, D-21335 Lüneburg Received: 19.2.2018 Accepted: 27.02.2018 Published: 03.10.2018 Abstract: In times of biodiversity loss due to climate change, the development of effective conservation strategies still requires extensive ecological research. Macroecological studies aim at the detection of large-scale taxonomic, geographic and temporal patterns and their potential drivers. Phylogeographic studies address the genetic level of biodiversity and are com- monly used to study species’ histories and locate glacial refugia. Newly established methods such as species distribution models (SDMs) project both historical as well as future distribution ranges of species. In my doctoral thesis I used a combined approach to gain new insights into the effect of climate change on diversity patterns of ground beetles. In further steps, I used macroecological regression models to detect spatial patterns in the distribution of mean carabid body size and the proportion of flightless species. Carabid body size showed a positive relati- onship with contemporary environmental productivity and stability, while patterns in hind wing develop- ment were most notably influenced by historical climate stability. In an online database (www.carabids.org) a large data set on Palaearctic carabid traits was made available for future studies. Phylogeographic analyses (using mtDNA) were combined with SDMs to identify multiple and isolated glacial refugia of Carabus irregularis, a cold-adapted, flightless ground beetles species. Strong intraspecific genetic differentiation was found between two ancient clades, which pointed to the existence of two evolu- tionarily significant units (ESUs). SDMs projected immense range contractions for both ESUs in future and thus high vulnerability of C. irregularis. Taken as a whole, this combination of methods is conducive to a better understanding of potential effects of historical, contemporary and future climate on diversity patterns of insects and on specialised species with low dispersal abilities. Keywords: body size, hind wing development, dispersal ability, traits, mtDNA, ecological significant units, species distribution models, range contractions, carabids.org 1 Introduction diversity, especially because ongoing climate change 1.1 Background is expected to increase diversity loss (Araújo & Rahbek 2006; Bellard et al. 2012; Pereira et al. Biodiversity is a vital factor for the functioning of 2012). Since effective conservation strategies still re- ecosystems, which provide ecological, economic and quire substantial research, many recent studies from a cultural services essential for human health and well- wide range of ecological disciplines aim at understan- being (Loreau et al. 2001; Hooper et al. 2005; ding the complex relationships between biodiversity MEA 2005). International conservation efforts (e.g. and climate on various taxonomic, geographic and based on the Convention on Biological Diversity: temporal scales (Wolters et al. 2006; Field et al. UNEP 1992) concentrate on the protection of bio- 2009; Hortal et al. 2011). Angewandte Carabidologie 12 (2018): 17–27 ISSN: 2190-7862 (Internet) ©Gesellschaft für Angewandte Carabidologie e.V. download www.laufkaefer The investigation of large-scale geographic diver- and the Alps (Bhagwat & Willis 2008; Provan & sity patterns has a long tradition and biogeographic Bennett 2008). rules such as Bergmann’s and Allen’s rule (Berg- Many phylogeographic analyses focus on the ge- mann 1847; Allen 1877) have long assumed relati- netic variation of widespread species (Hewitt 1999; onships between species characteristics (i.e. body size Schmitt 2007; Knopp & Merilä 2009; Valtu- and the size of body appendages) and environmental ena et al. 2012). Studies on mountain species with conditions (e.g. temperature). The study of broad- restricted and disjunct ranges are still scarce (but see scale patterns has undergone a revival over the last Schmitt 2009). few decades. Recent macroecological research aims at In order to identify and locate potential glacial re- the detection of statistical patterns in large ecological fugia, many studies using newly established modelling data sets and the potential mechanisms driving these methods such as species distribution models (SDMs) patterns (Brown & Maurer 1989; Blackburn have been used in association with palaeoclimatic & Gaston 1994). Species’ traits are increasingly data (Waltari et al. 2007; Elith & Leathwick used to examine spatial and temporal phenomena 2009). In addition to phylogeographic analyses, these of species diversity and distribution, ranging from modern approaches have also detected classical as well community organisation to ecosystem functioning as cryptic refugia (Vega et al. 2010; Rebelo et al. (Hooper et al. 2005; McGill et al. 2006; de Bel- 2012). However, there are still many uncertainties re- lo et al. 2010). Body size still appears to be the best garding glacial refugia, in particular for cold-adapted studied trait in animal species (e.g. Meiri et al. 2004; and low-dispersal mountain species. Consequently, Olalla-Tarraga et al. 2006; McNab 2010). In further research is needed to develop reasonable sce- 1847, Bergmann’s rule was originally formulated for narios of species’ population histories including range endotherms, and the pattern of increasing body size retractions and expansions during the last ice ages. towards high latitudes and cold environments still SDMs have been used for the projection of both applies for birds and mammals (e.g. Blackburn & historical as well as future distribution ranges of Hawkins 2004; Olson et al. 2009). Interestingly, species. Over the past century, Earth’s climate has the pattern has also been detected in some ectotherms changed immensely (IPCC 2007). Besides extinc- (Blackburn et al. 1999; Huey et al. 2000). Ho- tions, phenological shifts, and evolutionary responses, wever, in some invertebrates (e.g. spiders and ants), range shifts have been observed as potential reactions inconsistent relationships between body size and con- to climate change (Walther et al. 2002). SDMs are temporary climate have been identified, even in the increasingly used in the field of global change biolo- same geographic region (cf. Cushman et al. 1993; gy to detect species’ range shifts in times of climate Entling et al. 2010). Patterns were assumed to be change (Guisan & Thuiller 2005; Elith & Lea- shaped by different mechanisms linked to species’ thwick 2009). Numerous studies have documented physiological abilities ranging from energy allocation range shifts towards higher altitudes or latitudes (Atkinson 1995; Mousseau 1997), to starvation (Parmesan & Yohe 2003; Hickling et al. 2006). and desiccation resistance (Remmert 1981; Cush- Cold-adapted mountain species are considered to be man et al. 1993; Entling et al. 2010), and to disper- particularly sensitive to global warming, since it is as- sal abilities (Cushman et al. 1993). sumed that cool and moist habitats decrease in future The genetic level of biodiversity has been (Wilson et al. 2007; Settele et al. 2009; Dieker addressed by phylogeographic studies (e.g. analysing et al. 2011). An additional factor limiting the future sequences of mitochondrial DNA = mtDNA), which distribution ranges of many of these species might be are commonly used to identify and locate glacial their low dispersal ability (Svenning & Skov 2004; refugia. The southern European peninsulas are con- Schloss et al. 2012). In conjunction with future sidered as classical refugia, which were important for climate scenarios, SDMs can help to develop conser- species survival during past climatic events such as ice vation strategies for these vulnerable species, as they ages (Taberlet et al. 1998; Hewitt 2000). Cold- allow the location of regions that might be suitable for adapted (i.e. alpine and arctic) species are assumed to their future survival (Elith & Leathwick 2009; have survived in the margins of southern European Schwartz 2012). mountain chains (Stewart et al. 2010). Recent pu- Especially for invertebrate species, much more blications, however, document evidence for additio- research is still required to enhance our knowledge on nal refugia north of the southern European peninsulas 18 Angewandte Carabidologie 12 (2018) ©Gesellschaft für Angewandte Carabidologie e.V. download www.laufkaefer the complexity of diversity patterns and on relevant in the Palaearctic region, especially in Europe. In my drivers. appoach i applied methods from three fields of biolo- gical research – macroecology, phylogeography and 1.2 Study taxon global change biology – in order to gain new insights into the effect of climate on patterns