Management-driven evolution in a domesticated ecosystem

Abstract

Millennia of human land-use have resulted in the widespread occurrence of what have been coined 'domesticated ecosystems'. The anthropogenic imprints on diversity, composition, structure and functioning of such systems are well documented. However, evolutionary consequences of human activities in these ecosystems are enigmatic. Calluna vulgaris (L.) is a keystone species of coastal heathlands in northwest Europe, an ancient semi-natural landscape of considerable conservation interest. Like many species from naturally fire-prone ecosystems, Calluna shows smoke-adapted germination, but it is unclear whether this trait arose prior to the development of these semi-natural landscapes or is an evolutionary response to the anthropogenic fire regime. We show that smoke-induced germination in Calluna is found in populations from traditionally burnt coastal heathlands but is lacking in naturally occurring populations from other habitats with infrequent natural fires. Our study thus demonstrates evolutionary imprints of human land-use in semi-natural ecosystems. Evolutionary consequences of historic anthropogenic impacts on wildlife have been understudied, but understanding these consequences is necessary for informed conservation and ecosystem management.

Fire and plant diversity at the global scale

“…There are at least two (not mutually exclusive) mechanisms by which fire may drive plant diversity at the scale and grain considered here. The first is a selective process, as there is both micro-and macroevolutionary evidence suggesting that fire regime can drive population divergence and diversification (Bytebier et al, 2011;Crisp et al, 2011;G omez-Gonz alez et al, 2011;He et al, 2011He et al, , 2012Hern andez-Serrano et al, 2013;Pausas, 2015a;Vandvik et al, 2014). The second process suggests that fire generates landscape mosaics and thus more habitat types and more niches likely to be filled by different species (e.g., Bird, Bird, Codding, Parker, & Jones, 2008;Bond & Keeley, 2005;Cohn et al, 2015;Kelly et al, 2012;Parr & Brockett, 1999); in this sense, fire would generate the biotic heterogeneity that drives diversity (Stein et al, 2014), as proposed by the 'pyrodiversity begets diversity' hypothesis (Bowman et al, 2016;Martin & Sapsis, 1992).…”

“…For instance, fire is a disturbance with a very long evolutionary history (Pausas & Keeley, 2009), and recurrent fires have selected for specific plant persistence traits (Keeley, Pausas, Rundel, Bond, & Bradstock, 2011. Indeed, there is microevolutionary evidence suggesting that fire can drive phenotypic and genetic divergence within species (G omez-Gonz alez, Torres-Díaz, Bustos-Schindler, & Gianoli, 2011;Hern andez-Serrano, Verd u, Gonz alez-Martínez, & Pausas, 2013;Pausas 2015a;Pausas, Alessio, Moreira, & Corcobado, 2012;Vandvik et al, 2014). Likewise, macroevolutionary studies show the importance of fire in the diversification of some plant lineages (Bytebier, Antonelli, Bellstedt, & Linder, 2011;Crisp, Burrows, Cook, Thornhill, & Bowman, 2011;He, Lamont, & Downes, 2011;He, Pausas, Belcher, Schwilk, & Lamont, 2012).…”

Is palaeoecology a ‘special branch’ of ecology?

“…The meeting ground between the two branches appears to be both thematic, for example, related to climate change or landscape and land-use history (e.g. Telford et al, 2006; Vandvik et al, 2014; Vandvik and Goldberg, 2006), and methodological, relating to, for example, the development and application of quantitative methods and approaches (e.g. Bertrand et al, 2011).…”

“…Giesecke et al, 2008; Ohlemuller et al, 2012). Still, research on these and other shared topics remains largely separate, with little cross-fertilisation in terms of publications or projects that combine palaeoecological and ecological data and methods (but see, for example, Birks, 1996; Kapfer et al, 2013; Moe and Bjune, 2009; Vandvik et al, 2014; Willis et al, 2007). The two fields have different strengths, whereas ecology offers opportunities for high spatial-resolution experiments that can establish cause and effect, and have a broad range of predictor and response variables, palaeoecology offers unique insights into long-term landscape and population dynamics and can contrast our current Anthropocene setting (Ellis et al, 2012) with more natural past landscapes.…”

Biogeography of the Anthropocene

“…Recent research offers new ways to clarify human effects on landscapes, including the study of a) soil organic matter and chemistry over centuries, done by finding some sites unreachable by land use due to topography (Heitkamp et al, 2014); b) leaf and soil chemistry as affected by the particular species used in planted forests (Erickson et al, 2014); c) reciprocal interactions of plant species traits with vegetation functioning (Garnier et al, 2007); d) selection for fire-adapted genetic lineages in places burned by people (Vandvik et al, 2014); and e) hydrological effects of land cover manipulations and alterations (Ponette-González et al, 2014; Woodward et al, 2014). Studies in agricultural landscapes illustrate how farming practices affect abundances and types of native insects (Aizen et al, 2009; Puech et al, 2014) and birds (Frishkoff et al, 2014; Karp et al, 2012).…”