Resource allocation to testes in walnut flies and implications for reproductive strategy

Laura D. Carsten-Conner, Daniel R. Papaj, Diane M. O'Brien

Research output: Contribution to journalArticlepeer-review

5 Scopus citations


Testes size often predicts the winner during episodes of sperm competition. However, little is known about the source of nutrients allocated to testes development, or testes plasticity under varying nutrient availability. Among many holometabolous insects, metabolic resources can derive from the larval or adult diet. Distinguishing the source of nutrients allocated to testes can shed light on life history factors (such as maternal influences) that shape the evolution of male reproductive strategies. Here we used an experimental approach to assess resource allocation to testes development in walnut flies (Rhagoletis juglandis) from differing nutritional backgrounds. We fed adult male walnut flies on sugar and yeast diets that contrasted with the larval diet in carbon and nitrogen stable isotope ratios. This design allowed us to assess the dietary source of testes carbon and nitrogen and its change over time. We found significant incorporation of adult dietary carbon into testes, implying that walnut flies are income breeders for carbon (relying more on adult resources). In contrast, we found little evidence that walnut flies incorporate adult dietary nitrogen into testes development. We discuss the implications of these allocation decisions for life history evolution in this species.

Original languageEnglish (US)
Pages (from-to)1523-1529
Number of pages7
JournalJournal of Insect Physiology
Issue number11
StatePublished - Nov 2010


  • Capital breeding
  • Income breeding
  • Insects
  • Sperm competition
  • Stable isotope

ASJC Scopus subject areas

  • Physiology
  • Insect Science


Dive into the research topics of 'Resource allocation to testes in walnut flies and implications for reproductive strategy'. Together they form a unique fingerprint.

Cite this