12Oct 2017

CRANIOMETRIC ANALYSIS OF ONTOGENETIC VARIATION AND SEXUAL DIMORPHISM IN THE EAST AFRICAN ROOT RAT, TACHYORYCTES SPLENDENS (RODENTIA: SPALACIDAE) FROM TANZANIA.

  • Department of Zoology & Wildlife Conservation, College of Natural and Applied Sciences, University of Dar es Salaam, P.O.Box 35064, Dar es Salaam, Tanzania.
  • Department of Zoology & Entomology, University of Pretoria, Private Bag X20, Hatfield, 0028 South Africa.
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Ontogenetic variation and sexual dimorphism in the East African root rat, Tachyoryctes splendens (R?ppell 1835) from Tanzania, East Africa were examined using craniometric and body mass data. Ontogenetic variation was based on tooth eruption and wear in five relative age classes and revealed significant craniometric variation between them. Sexual dimorphism was evident in all three populations examined and revealed that males are larger in body size than females. The results of craniometric analysis of ontogenetic variation and sexual dimorphism in T. splendens are also reflected in the analysis of body mass data. These results suggest that male T. splendens invest energy into growth to facilitate male-male competition and sexual selection during the breeding season. Females however, show conservative growth with most energy being utilized for the excavation of complex burrow systems to increase foraging efficiency and allow for maternal care. Individuals of relative age classes 4 and 5 are reproductively mature and are thus capable of procreation.

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[Jestina Venance Katandukila. (2017); CRANIOMETRIC ANALYSIS OF ONTOGENETIC VARIATION AND SEXUAL DIMORPHISM IN THE EAST AFRICAN ROOT RAT, TACHYORYCTES SPLENDENS (RODENTIA: SPALACIDAE) FROM TANZANIA. Int. J. of Adv. Res. 5 (Oct). 488-508] (ISSN 2320-5407). www.journalijar.com

Jestina Venance Katandukila
Department of Zoology & Entomology, University of Pretoria, Private Bag X20, Hatfield, 0028 South Africa; Department of Zoology & Wildlife Conservation, College of Natural and Applied Sciences, University of Dar es Salaam, P.O.Box 35064, Dar es Salaam, Tanzania

DOI:

Article DOI: 10.21474/IJAR01/5553      
DOI URL: https://dx.doi.org/10.21474/IJAR01/5553

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