Do juvenile developmental and adult body characteristics differ among genotypes at the doublesex locus that controls female-limited Batesian mimicry polymorphism in Papilio memnon?: A test for the "cost of mimicry" hypothesis. (May 2018)

• Record Type: Journal Article
• Authors: Komata, Shinya; Lin, Chung-Ping; Sota, Teiji
• Is Part Of: Journal of insect physiology. Volume 107(2018)
• Page Start: 1
• Page End: 6
• Publication Date: 2018-05
• Subjects: Batesian mimicry -- Doublesex gene -- Female-limited polymorphism -- Juvenile development -- Physiological costs -- Sex ratio; Insects -- Physiology -- Periodicals; Insectes -- Physiologie -- Périodiques; Insects -- Physiology; Periodicals; 571.157
• DOI: 10.1016/j.jinsphys.2018.02.001
• Languages: English
• ISSNs: 0022-1910

Abstract

Graphical abstract: Highlights: Offspring genotype frequencies in Hh × Hh crosses followed the Mendelian ratios. Developmental and adult characteristic did not differ among doublesex genotypes. Some developmental and adult characteristics were affected by sex and day length. No evidence for physiological costs associated with the mimetic genotypes was found. Abstract: Female-limited Batesian mimicry may have evolved because of stronger predation pressure on females than on males, but some physiological costs of mimicry may also hinder the evolution of mimicry in males. In Papilio memnon, which possesses a female-limited Batesian mimicry polymorphism, two alleles at the doublesex ( dsx ) locus strictly control female phenotypes. To examine whether there are physiological costs associated with mimetic genotypes in the juvenile stage, we compered mortality, juvenile growth and development, and the resultant adult characteristics among three dsx genotypes ( HH, Hh, hh ) at a constant temperature (25 °C) and two differing day lengths (LD 14:10 and LD 12:12; the latter might induce pupal diapause) by crossing individuals heterozygous ( Hh ) for the dsx allele. All pupae emerged directly without diapause irrespective of day length. The genotype frequencies of the emerged individuals were consistent with the expected 1:2:1 ratio of HH : Hh : hh . The sex ratio was significantly male-biased in one of two families, but not in the other. We found no effect of genotype on any developmental or adult characteristic, although there were sex differences in most traits. The larval development time was longer and growth rate higher in females than in males; pupal weight, forewing length, and total dry mass of the thorax and abdomen were greater in females, whereas the thoracic mass/abdominal mass ratio was greater in males. We also found that the growth rate was higher and pupal period longer with a short day than with a long day. Overall, we found no evidence for physiological costs associated with the mimetic genotypes. However, it is too early to conclude that no physiological cost of mimicry affects the evolution and maintenance of this female-limited Batesian mimicry polymorphism because we have not studied the adults of different genotypes.