RT Journal Article
SR Electronic
T1 Adaptation to larval crowding in <em>Drosophila ananassae</em> and <em>Drosophila nasuta nasuta</em>: increased larval competitive ability without increased larval feeding rate
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 011684
DO 10.1101/011684
A1 Archana Nagarajan
A1 Sharmila Bharathi Natarajan
A1 Mohan Jayaram
A1 Ananda Thammanna
A1 Sudarshan Chari
A1 Joy Bose
A1 Amitabh Joshi
YR 2014
UL http://biorxiv.org/content/early/2014/11/20/011684.abstract
AB The canonical view of adaptation to larval crowding in fruitflies, built on results from 25 years of experimental evolution studies on D. melanogaster, is that enhanced competitive ability evolves primarily through increased larval feeding and foraging rate, at the cost of efficiency of food conversion to biomass, and increased larval tolerance to nitrogenous wastes. We show that populations of D. ananassae and D. n. nasuta subjected to extreme larval crowding evolve greater competitive ability and pre-adult survivorship at high density primarily through a combination of reduced larval duration, faster attainment of minimum critical size for pupation, greater efficiency of food conversion to biomass, increased pupation height and, perhaps, greater urea/ammonia tolerance. This is a very different suite of traits than that seen to evolve under similar selection in D. melanogaster and seems to be closer to the expectations from the canonical theory of K-selection. We discuss possible reasons for these differences in results across the three species. Overall, the results reinforce the view that our understanding of the evolution of competitive ability in fruitflies needs to be more nuanced than before, with an appreciation that there may be multiple evolutionary routes through which higher competitive ability can be attained.