The consequences of parental age for development, body mass and resistance to stress in the red flour beetle

Abstract

The performance of most animals deteriorates with age. Motivated by the inconsistency in the literature regarding the effect of parental age on offspring traits and performance, we studied how parental age affects offspring development time, body mass, and starvation and cold tolerance in the red flour beetle (Tribolium castaneum). Offspring of old parents pupated later and at a higher body mass, and there was a general positive correlation between body mass and starvation tolerance. Despite their higher body mass, offspring of old parents tolerated starvation less well than those of young parents, emphasizing the impaired performance of the former. However, parental age did not affect offspring thermal tolerance and offspring of old parents were not more sensitive to cold shock than those of young parents. We also examined how ageing affects body mass and cold tolerance in the parental generations. By contrast to the effect of ontogeny on thermal tolerance, which is better known, change in thermal tolerance with age is seldom studied and can take different shapes. Old beetles were more sensitive to cold shock than younger beetles. Similar to cold tolerance, body mass decreased with age. In summary, older beetles reflect a worse physiological condition than younger ones. Ageing leads to impaired cold tolerance, lower body mass, lower number of offspring reaching adulthood, and deteriorated performance of the offspring, expressed as a lower starvation tolerance and a longer development time of the offspring.

Effects of Thermal Regimes, Starvation and Age on Heat Tolerance of the Parthenium Beetle Zygogramma bicolorata (Coleoptera: Chrysomelidae) following Dynamic and Static Protocols

“…In food-deprived beetles, resources declined continuously with age, while young beetles may initially gain mass and store additional resources before effects of senescence become dominant. These results are in line with others showing a negative relationship between age and thermotolerance in insects [32,33,80,81]. However, an increase in thermotolerance with age has also been reported [37], suggesting that responses may be stress- and species-specific.…”

“…Hardening at 33°C elicited similar hardening responses except in old beetles (Fig 3). Such ability for rapid heat hardening has been reported in various studies [9,33,50]. Pre-exposure to low temperatures may also enhance survival at high temperatures, typically referred to as cross-tolerance [9,22].…”

“…Some studies have shown that thermal plasticity is also influenced by age [32,33] and ontogeny [21,35], though our knowledge on such effects are still poor especially due to partly contrasting results [35,36]. For example, while aging resulted in improved cold tolerance in the wingless fly Anatalanta aptera (Diptera: Sphaeroceridae) [37], it decreased cold tolerance in the red flour beetle T .…”

“…For example, while aging resulted in improved cold tolerance in the wingless fly Anatalanta aptera (Diptera: Sphaeroceridae) [37], it decreased cold tolerance in the red flour beetle T . castaneum (Coleoptera: Tenebrionidae) [33]. In the fruit flies Ceratitis capitata and C .…”

An invitation to measure insect cold tolerance: Methods, approaches, and workflow

“…Some care may need to be taken to control for aging if this is a potential factor in lengthy acclimation treatments, as aging can decrease (e.g. Halle et al, 2015) pre-treated groups can be directly compared to that of controls, using t-tests, ANOVA with planned comparisons, or GLZ (with binomial error distributions) and planned comparisons.…”