Behavioral trajectories as predictors in event history analysis: Male calling behavior forecasts medfly longevity

Abstract

A recent study on wild male Mediterranean fruit flies [Papadopoulos, N.T., Katsoyannos, B.I., Kouloussis, N.A., Carey, J.R., Müller, H.-G., Zhang, Y., 2004. High sexual signalling rates of young individuals predict extended life span in male Mediterranean fruit flies. Oecologia 138,[127][128][129][130][131][132][133][134] provided evidence that intense sexual signalling (calling behavior) is associated with longer life span. We demonstrate here an approach based on functional data analysis methodology for predicting individual remaining longevity and the distribution of remaining lifetime from individual behavioral trajectories. A key methodological concept is the time evolution of mean functions and eigenfunctions. This methodology is applied to the event history of calling behavior of male medflies. The results demonstrate complex relationships between male calling behavior and subsequent longevity that complement previous biodemographic analyses of these data. A high level of recent calling activity is found to be associated with increased remaining lifetime for an individual male fly, while calling activity at early ages plays no role for remaining longevity.

Dual reproductive cost of aging in male medflies: Dramatic decrease in mating competitiveness and gradual reduction in mating performance

“…The existence of non-calling males is not fully understood yet and may be caused by male – male aggression or by genetic factors (Shelly, 2000). It appears that age and time of the day can also affect the emission of pheromone (Flath et al, 1993; Papadopoulos et al, 1998; Papadopoulos et al, 2004; Zhang et al, 2006; Neto et al, 2009). It is known that frequently calling males usually achieve higher mating success (Shelly, 2000).…”

An evolutionary heterogeneity model of late-life fecundity in Drosophila

“…In addition, Carey (2003) has noted that males exhibit a characteristic supine behavior prior to death. Current male calling behavior in medflies may also be used to predict remaining lifespan (Zhang et al 2006). These observations suggest a physiological decline prior to death that may exhibit its effects in a variety of characters, not just female fecundity.…”

Age-Dependent Stability of Sensorimotor Functions in the Life-Extended Drosophila mutant Methuselah

“…In this experiment we measured WBF at 5 days of age conditioned on an individual fly's lifespan. This approach to determining the correlation between biological function at a particular age and longevity has previously been used to study functional aging in flies, for example, to determine the rate of egg laying at a particular age conditioned on lifespan (Carey et al 2005), effects of the onset of dietary restrictions on subsequent longevity (Mair et al 2003;Vaupel et al 2003), and association between the intensity of a male fly's sexual signaling (e.g., calling behavior) and lifespan (Papadopoulos et al 2004;Zhang et al 2006). Figure 5 shows results of this experiment.…”