Effects of variation in resource acquisition during different stages of the life cycle on life‐history traits and trade‐offs in a burying beetle

Abstract

Individual variation in resource acquisition should have consequences for life‐history traits and trade‐offs between them because such variation determines how many resources can be allocated to different life‐history functions, such as growth, survival and reproduction. Since resource acquisition can vary across an individual's life cycle, the consequences for life‐history traits and trade‐offs may depend on when during the life cycle resources are limited. We tested for differential and/or interactive effects of variation in resource acquisition in the burying beetle Nicrophorus vespilloides. We designed an experiment in which individuals acquired high or low amounts of resources across three stages of the life cycle: larval development, prior to breeding and the onset of breeding in a fully crossed design. Resource acquisition during larval development and prior to breeding affected egg size and offspring survival, respectively. Meanwhile, resource acquisition at the onset of breeding affected size and number of both eggs and offspring. In addition, there were interactive effects between resource acquisition at different stages on egg size and offspring survival. However, only when females acquired few resources at the onset of breeding was there evidence for a trade‐off between offspring size and number. Our results demonstrate that individual variation in resource acquisition during different stages of the life cycle has important consequences for life‐history traits but limited effects on trade‐offs. This suggests that in species that acquire a fixed‐sized resource at the onset of breeding, the size of this resource has larger effects on life‐history trade‐offs than resources acquired at earlier stages.

Age‐dependent plasticity in reproductive investment, regeneration capacity and survival in a partially clonal animal (Hydra oligactis)

“…Allocation of resources to basic life functions often shows age‐ or life stage‐dependent plasticity (Radchuk, Turlure, & Schtickzelle, 2013; Richardson & Smiseth, 2019). For instance, an increase in fecundity with age is common in both indeterminate and determinate growers (Berube, Festa‐Bianchet, & Jorgenson, 1999; Clutton‐Brock, 1984; Martin, 1995), because when growth stops or declines after maturity, it is optimal to direct the remaining resources into reproduction (Cichoń, 2001).…”

“…Due to competition over limited energy or nutrients, age‐dependent allocation strategies can shape all main life‐history components responsible for growth, reproduction, somatic maintenance or survival by trade‐offs between them (Kozłowski, 1992, but see Cox, Lovern, & Calsbeek, 2014). Resource acquisition can reduce the extent of these trade‐offs in ‘high quality individuals’ via buffering temporary resource limitation, but resource acquisition also varies with an individual's life cycle and is more important for resource allocation at early ages (Richardson & Smiseth, 2019; Yearsley et al., 2005).…”

Food deprivation affects egg laying and maternal care but not offspring performance in a beetle

“…Most prior work has focused on a relatively limited number of traits associated with reproduction (e.g. Hörnfeldt & Eklund 1990;Clifford & Anderson 2001;Richardson & Smiseth 2019a). However, in many species, reproduction involves complex suites of traits expressed in both parents and offspring.…”

“…These reproductive traits have important consequences for offspring performance as increased hatching asynchrony negatively affects offspring growth and survival (Ford & Smiseth 2016;Ford & Smiseth 2018), whilst greater investment in parental care improves offspring growth and survival (Andrews et al 2016). Prior work shows that nutritional state has important consequences for reproduction as food-deprived females lay fewer eggs (Steiger et al 2007), and have fewer adult offspring (Gray et al 2018;Richardson & Smiseth 2019a). However, there is a lack of information on how food deprivation influences suites of reproductive traits that are expressed at different times in the breeding cycle and in both parents and offspring.…”

Early‐life effects on body size in each sex interact to determine reproductive success in the burying beetle Nicrophorus vespilloides

“…In addition, adult size influences female fecundity. Larger females lay more eggs (Jarrett et al., 2017; Steiger, 2013), the eggs are larger than those laid by smaller females (Richardson & Smiseth, 2019), and they produce heavier larvae (Steiger, 2013). Larger females are also more inclined to practice partial filial cannibalism (Bartlett & Ashworth, 1988; Jarrett et al., 2017).…”