Parental effects influence life history traits and covary with an environmental cline in common frog populations

Abstract

Across latitudinal clines, the juvenile developmental rates of ectotherms often covary with the length of the growing season, due to life-history trade-offs imposed by the time-constrained environments. However, as the start of the growing season often varies substantially across years, adaptive parental effects on juvenile developmental rates may mediate the costs of a delayed season. By employing a meta-analysis, we tested whether larval developmental rates across a latitudinal cline of the common frog (Rana temporaria) are affected by fluctuating onsets of breeding, across years. We predicted that larval developmental rate will be inversely related to the onset of breeding, and that northern populations will be more prone to shorten their developmental rate in response to late breeding, as the costs of delayed metamorphosis should be highest in areas with a shorter growing season. We found that the larval period of both northern and southern populations responded to parental environmental conditions to a similar degree in absolute terms, but in different directions. In northern populations, a late season start correlated with decreased development time, suggesting that the evolution of parental effects aids population persistence in time-constrained environments. In southern populations, late season start correlated with increased development time, which could potentially be explained as a predator avoidance strategy. Our findings suggest that local ecological variables can induce adaptive parental effects, but responses are complex, and likely trade-off with other ecological factors.

Limits to compensatory responses to altered phenology in amphibian larvae

“…In our study, individuals that experienced a hatching delay after the exposure to cold temperature that arrested embryonic development, accelerated larval development, metamorphosed in a shorter time, and recovered most of the developmental delay, even after a 12‐day hatching delay. These results agree with theoretical models that predict faster life histories in organisms facing time‐constrained environments (Rowe and Ludwig 1991, Werner and Anholt 1993, Abrams et al 1996), and confirm a common pattern observed in many ectotherms living in seasonal environments (Johansson and Rowe 1999, De Block and Stoks 2004, 2005, Gotthard 2008, Śniegula et al 2012, Rowiński et al 2020), including amphibians (Orizaola et al 2010, 2016Richter‐Boix et al 2014). Developmental acceleration in response to phenological change took place with little change in mass at metamorphosis within each temperature–food treatment, which likely reflects the ecological relevance that body mass has for fitness during the adulthood in ectotherms, and specifically in species with complex life cycles (Rowe and Ludwig 1991, Altwegg and Reyer 2003, Earl and Whiteman 2015).…”

Grow fast but don't die young: Maternal effects mediate life‐history trade‐offs of lizards under climate warming

“…In contrast, maternal effects may also be neutral or even negative for offspring fitness in some populations (Marshall & Uller, 2007; Mousseau & Fox, 1998; Telemeco et al., 2017). Nonetheless, despite the importance of maternal effects in the flexible and rapid responses of ectothermic vertebrates to environmental change (Galloway & Etterson, 2007; Ma et al., 2014; Rando & Verstrepen, 2007; Rowinski et al., 2020; Shama et al., 2014), how maternal effects shape offspring life‐history traits remain poorly understood.…”

Carryover effects from environmental change in early life: An overlooked driver of the amphibian extinction crisis?

“…Importantly, UVR impacts on DNA damage, methylation, chromatin remodelling and gene expression patterns that may have epigenetic consequences affecting survivability of the next generation (De Oliveira et al, 2020;Ho & Burggren, 2010;Rowinski et al, 2020). For example, Ding et al (2019) observed UVRinduced trans-generational effects on hatching success and larval size in sea urchins (Strongylocentrotus intermediusa).…”