Age-based mate choice improves reproductive performance and offspring attributes in parthenium beetle,Zygogramma bicolorata(Coleoptera: Chrysomelidae)

Abstract

The present study was designed to investigate the influence of mate choice in terms of age on reproductive performance and offspring attributes of parthenium beetle, Zygogramma bicolorata Pallister (Coleoptera: Chrysomelidae). Age-based mate choice was most evident in the middle-aged adults. Results revealed that middle-aged males and females were significantly preferred as mates by their middle-aged counterparts. Younger and older females did not show any preference for males of any age group. On the other hand, younger males showed a bias against old females, while older ones did not show any age-based preference for mates. Both fecundity and percent egg viability were significantly influenced by female and male age, respectively. Fecundity was highest in middle-aged females followed by young- and old-aged ones, with similar trend observed in relation to male age effects on egg viability. The development and survival of immature stages borne out of mate choice decisions of adults was influenced by mother's age. Offspring of middle-aged females developed fastest and survived longer than those of younger and older ones.

The influence of female age on male mating preference and reproductive success in cabbage beetle, Colaphellus bowringi

“…For example, in checkered white butterfly Pieris protodice (Rutowski, ), fruit fly Drosophila hibisci (Polak et al ., ) and polygamous moth Ephestia kuehniella (Xu & Wang, ), males showed a mating preference for young females. However, in the parthenium beetle, Zygogramma bicolorata , middle‐aged males were significantly preferred as mates by their middle‐aged counterparts, but younger males showed a bias against old females, while older ones did not show any age‐based preference for mates (Pandey & Omkar, ).…”

“…The hatching rate of eggs laid by middle‐aged females was significantly higher than that of those laid by young and old females, while the longevity of males was not significantly affected by female age. Similar results of female mating success have been reported in ladybird beetle Menochilus sexmaculatus and Coccinella transversalis (Dixon & Agarwala, ), fruit flies D. ananassae and D. bipectinata (Prathibha & Krishna, ; Somashekar et al ., ), aphidophagous ladybird beetle Coelophora saucia (Omkar et al ., ) and parthenium beetle, Z. bicolorata (Pandey & Omkar, ), showing a parabolic trend or triangular function in terms of fecundity and fertility with the age at mating of females. This suggests that the reproductive physiology of female C. bowringi changes with their age and middle‐aged females tend to offer greater reproductive returns to males than younger or older ones.…”

“…Traditionally, females often invest more in parental care and are expected to be selective, while males typically show lower parental investment and hence are expected to be less selective (Trivers, ; Owens & Thompson, ; Johnstone et al ., ). However, recent studies have suggested that when the cost of reproduction for males and variance in female quality are high, males are predicted to show adaptive mate choice (Bonduriansky, , ; Byrne & Rice, ; Chenoweth et al ., ; Barry & Kokko, ; Edward & Chapman, ; Nandy et al ., ; Pandey & Omkar, ).…”

“…Therefore, when males encounter multiple females of different ages simultaneously, they should prefer those females that tend to maximize their expected fertilization success from each mating. Such preferences tend to favor females with a phenotype associated with high fecundity (Bonduriansky, ; Pandey & Omkar, ). To our knowledge, the empirical evidence of male mate choice based on female age have been reported only in a few insects and other animal species, showing mate preference for females of a particular age (Bonduriansky, ; Muller et al ., ; Pandey & Omkar, ).…”

“…Such preferences tend to favor females with a phenotype associated with high fecundity (Bonduriansky, ; Pandey & Omkar, ). To our knowledge, the empirical evidence of male mate choice based on female age have been reported only in a few insects and other animal species, showing mate preference for females of a particular age (Bonduriansky, ; Muller et al ., ; Pandey & Omkar, ). Furthermore, males will benefit when they bias their mating efforts toward females of higher reproductive potential (Reinhold et al ., ; Byrne & Rice, ; Omkar et al ., ; Pandey & Omkar, ).…”