Abstract
Ageing and its affect on life attributes have not been widely explored in ladybirds. The present study investigates the influence of female and male age at mating on the reproductive attributes of the ladybird beetle, Coelophora saucia (Mulsant). All reproductive attributes, viz. fecundity, percentage egg hatch, pre-oviposition, oviposition and post-oviposition periods were found to be influenced by the ages of both females and males at mating. This is unlike the results of previous studies on ladybirds, where male age was found to influence only percentage egg hatch. The influence of male age at mating on fecundity and reproductive periods is probably due to age influenced variation in seminal proteins, which influence fecundity and when the eggs are laid.
Highlights
Senescence can be defined demographically as an agedependent increase in mortality risk, or functionally as a decline in performance (Medawar, 1952; Williams, 1957; Rose, 1991; Partridge & Gems, 2002), and can be accounted for by several evolutionary and mechanistic theories
The results reveal that the ages of both the female and male at mating affect reproductive performance in C. saucia
Viz. Propylea dissecta (Mulsant), Cheilomenes sexmaculata (Fabricius), and Coccinella septempunctata Linnaeus revealed the effect of male age is limited to percentage egg hatch and had no effect on fecundity and the length of the reproductive period (Pervez et al, 2004; Srivastava & Omkar, 2004; Mishra & Omkar, 2004; Omkar et al, 2006)
Summary
Senescence can be defined demographically as an agedependent increase in mortality risk, or functionally as a decline in performance (Medawar, 1952; Williams, 1957; Rose, 1991; Partridge & Gems, 2002), and can be accounted for by several evolutionary and mechanistic theories (see Hughes & Reynolds, 2005). The understanding of the ageing process is based on the relationship between the demographic and functional aspects, which are believed to be tightly linked, as ageing involves a decline in performance of several body functions, leading to increased mortality (Williams, 1999), and is observed in organisms ranging from flies (Grotewiel et al, 2005) to human beings (Burke & Barnes, 2006) This decline in physiological performance with age is known to be influenced by a number of factors prominent amongst which are dietary restrictions (Piper & Partridge, 2007 and references therein) and reproduction (Rose, 1984; Finch, 1990, 1998; Tatar et al, 1993; Partridge et al, 1999; Finch & Ruvkun, 2001; Robine, 2001).
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
