Life history traits of spider mites and their relationship: A test of trade-off theory

Abstract

Trade-off theory has long been the central to evolutionary biology and is extensively employed to explain the correlations between life-history traits. It is generally accepted that trade-off occurs when one trait cannot increase without a decrease in another. In this study, we collected data on spider mites (70 papers for females and 35 papers for males) and explored the relationships between life-history traits to test the trade-off theory in both sexes. The results demonstrate that for both males and females, there was a statistically significant negative correlation between developmental rate and lifespan, in agreement with the trade-off theory. However, in contradiction with our assumption, the developmental rate of females was positively correlated with maximum daily fecundity, but not with the total fecundity. This indicates that developing fast does not necessarily bring the cost to late life-history traits. The long-lived females also showed higher lifetime fecundity, contrary to our prediction that investment in survival comes at the cost of lower investment in reproduction. These fundings are congruent with life history theory in that spider mites “live fast, die young”, convincing the trade-off between growth and longevity. Nevertheless, this study highlights that there is no clear evidence that spider mites trade off growth and survival for reproduction. The implications of this phenomenon are discussed.