Caste-specific phenotypic plasticity of Asian weaver ants: Revealing the allometric and non-allometric component of female caste system of Oecophylla smaragdina (Hymenoptera: Formicidae) by using geometric morphometrics


  • K. V. Mahima University of Calicut, Kerala, India
  • P. P. Anand University of Calicut, Kerala, India
  • S. Seena University of Calicut, Kerala, India
  • K. Shameema University of Calicut, Kerala, India
  • E. M. Manogem University of Calicut, Kerala, India
  • Y. Shibu Vardhanan University of Calicut, Kerala, India



Asian weaver ant, caste system, Geometric morphometric, polyphenism, Oecophylla smaragdina.


In eusocial insects, particularly in ants, caste differentiation is extremely complicated when we rely on traditional taxonomy. In most species, the worker caste does not display any distinct morphological characters neither the caste’s central division according to their morphological size variations. We used a landmark-based geometric morphometric approach to quantify the morphological characteristics of female caste systems (queen, major and minor worker ant) of Oecophylla smaragdina. Our findings suggested that each caste has its unique shape and size. Especially in the worker caste, apart from the size variations, we can use the shape as a prominent tool for distinguishing between them. The O. smaragdina exhibits a triphasic allometry pattern. Studying the allometry and non-allometry components of each caste system revealed a highly complex size and shape relationship in the female caste systems. From the allometric and non-allometric analysis, we concluded that the major worker ants showed a closer relationship with the queen than the minor worker ant. This outcome demonstrated that Asian weaver ant exhibits complex shape variations related to size and is correlated to their functional modular characters. This research sheds new light on caste systems’ taxonomic uncertainties for eusocial hymenopteran groups, especially ants.

Author Biographies

K. V. Mahima, University of Calicut, Kerala, India

Biochemistry & Toxicology Division, Department of Zoology, University of Calicut, Kerala, India 673 635

P. P. Anand, University of Calicut, Kerala, India

Research Scholar, Biochemistry & Toxicology Division, Department of Zoology, University of Calicut, Kerala, India 673 635

S. Seena, University of Calicut, Kerala, India

Research Scholar, Biochemistry & Toxicology Division, Department of Zoology, University of Calicut, Kerala, India 673 635

K. Shameema, University of Calicut, Kerala, India

Biochemistry & Toxicology Division, Department of Zoology, University of Calicut, Kerala, India 673 635

E. M. Manogem, University of Calicut, Kerala, India

Associate Professor, Insect Endocrinology Laboratory, Department of Zoology, University of Calicut, Kerala, India. 673 635

Y. Shibu Vardhanan, University of Calicut, Kerala, India

Associate Professor, Biochemistry & Toxicology Division, Department of Zoology, University of Calicut, Kerala, India 673 635


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How to Cite

Mahima, K. V., Anand, P. P., Seena, S., Shameema, K., Manogem, E. M., & Shibu Vardhanan, Y. (2021). Caste-specific phenotypic plasticity of Asian weaver ants: Revealing the allometric and non-allometric component of female caste system of Oecophylla smaragdina (Hymenoptera: Formicidae) by using geometric morphometrics. Sociobiology, 68(2), e5941.



Research Article - Ants