The BCB Staff Profile - Retha Hofmeyr
 

The Geometric Tortoise
 

The BCB Staff Profile

Margaretha Hofmeyr

Tel: +27 21 959 2313
Email: mdhofmeyr@uwc.ac.za

Undergraduate courses:

BDC 211: Animal Diversity - Vertebrates
The module provides an overview of vertebrate evolution and investigates the structure and function of systems relevant to the identification and classification of all major vertebrate groups.

BDC 311: Animal Ecophysiology and Biodiversity Assessment
Animal Ecophysiology explores how animals function in selected ecosystems with reference to energy, temperature and water relations. The Biodiversity Assessment component encompasses: Principles and context of survey design; Statistical constraints on survey design; Indices of species and genetic diversity; Techniques for analysing genetic, species and habitat diversity in marine and terrestrial environments; Collecting physical environmental data; Integrating, analyzing and interpreting information on biodiversity.

Postgraduate courses:

BCB 733: Herpetology
This module if offered by staff from UWC, US and Cape Nature. Course content includes: Evolution and diversity of amphibians and reptiles; Biogeography and Conservation of southern African herpetofauna; Amphibian declines; Anuran vocalization and breeding; Reptile reproduction and life history traits; Lizard social behaviour; Amphibian and reptile thermobiology; Herpetofaunal models in applied science.

Research Focus:

Southern Africa has one third of the world’s tortoise species; my research focus is on the biodiversity and conservation of southern African chelonians (tortoises and turtles). We assess biodiversity by studying the distribution, genetics, morphology, ecology and physiology of chelonians and concentrate efforts on the endemic taxa of the Cape Floristic Region and Succulent Karoo. Our research provides information on the life histories, resource requirements, reproductive ecology, and physiological tolerances of chelonians. Apart from advancing the conservation of tortoises, our studies advance science by adding new insights into the evolution of life histories in arid and unpredictable environments.

Other research interests include the reproductive biology of marine species and the interaction of arid-adapted animals with their environment. I studied the physical processes underlying heat exchange, and the physiological and behavioural responses of animals to cope with extreme conditions.

RESEARCH

Ecophysiology

·         Animal ecophysiological studies. 

Reproduction: We use ultrasound scanning and radiography to investigate reproductive cycles of female tortoises in their natural environment. These state of the art studies provide information important to the conservation of species and broaden our understanding of life histories in South African ecosystems.

Feeding ecology: Feeding habits and food preferences are studies through observation and by histological evaluation of faecal samples. Epidermal fragments of plants in the faeces are compared to a reference collection of plant epidermi from the habitat.

Baseline health: Baseline values of blood parameters are needed before it becomes possible to evaluate the effect of disease or stress on natural populations. We collect blood samples for haematological evaluation and to test chemical parameters in the plasma. Animals are also evaluated for ectoparasites, such as ticks, and the incidence of blood parasites.

Recent research outputs:

Peer-reviewed papers and book chapters:

Hofmeyr, M.D., Boycott, R.C. & Baard, E.H.W. 2011. Family Testudinidae. In: Bates, M.F., Branch, W.R., Bauer, A.M., Burger, M., Marais, J., Alexander, G.J. & de Villiers, M.S. (Eds.) Atlas and Red List of the Reptiles of South Africa, Lesotho and Swaziland. South African Biodiversity Institute, Pretoria, in press.

Loehr, V.J.T., Henen, B.T. and Hofmeyr, M.D. 2011. Reproductive responses to rainfall in the smallest tortoise, Homopus signatus signatus. Copeia, in press.

Vargas-Ramírez, M., Vences, M., Branch, W.R., Daniels, S.R., Glaw, F., Hofmeyr, M.D., Kuchling, G., Maran, J., Papenfuss, T.J., Široký, P., Vieites, D.R. and Fritz, U. 2010. Deep genealogical lineages in the widely distributed African helmeted terrapin: evidence from mitochondrial and nuclear DNA (Testudines: Pelomedusidae: Pelomedusa subrufa). Molecular Phylogenetics and Evolution 56: 428-440.

Fritz, U., Daniels, S.R. and Hofmeyr, M.D. 2010. Mitochondrial phylogeography and subspecies of the wide-ranging sub-Saharan leopard tortoise Stigmochelys pardalis (Reptilia: Testudines: Testudinidae) – a case study for the pitfalls of pseudogenes and GenBank sequences. Journal of Zoological Systematics and Evolutionary Research 48(4): 348-359.

Daniels, S.R., Hofmeyr, M.D., Henen, B.T. and Baard, E.H.W. 2010. Systematics and phylogeography of a threatened tortoise, the speckled padloper. Animal Conservation 13(3): 237-246.

Joshua, Q.I., Hofmeyr, M.D. and Henen, B.T. 2010. Seasonal and site variation in Angulate Tortoise diet and activity. Journal of Herpetology 44(1): 124-134.

Loehr, V.J.T., Hofmeyr, M.D. and Henen, B.T. 2009. Small and sensitive to drought: consequences of aridification to the conservation of Homopus signatus signatus. African Herpetology 58(2): 116-125.

Hofmeyr, M.D. 2009. Chersina angulata (Schweigger 1812) – angulate tortoise, South African bowsprit tortoise. In: Rhodin, A.G.J., Pritchard, P.C.H., van Dijk, P.P., Saumure, R.A., Buhlmann, K.A., Iverson, J.B., and Mittermeier, R.A. (Eds.). Conservation Biology of Freshwater Turtles and Tortoises: A Compilation Project of the IUCN/SSC Tortoise and Freshwater Turtle Specialist Group. Chelonian Research Monographs No. 5, pp. 030.1-030.6, doi:10.3854/crm.5.030.angulata.v1.2009, http://www.iucn-tftsg.org/cbftt/.

Daniels, S.R., Hofmeyr, M.D., Henen, B.T. and Crandall, K.A. 2007. Living with the genetic signature of Miocene induced change: evidence from the phylogeographic structure of the endemic angulate tortoise Chersina angulata. Molecular Phylogenetics and Evolution 45: 915-926.

Loehr, V.J.T., Hofmeyr, M.D. and Henen, B.T. 2007. Growing and shrinking in the smallest tortoise, Homopus signatus signatus: the importance of rain. Oecologia 153: 479-488.

Loehr, V.J.T., Hofmeyr, M.D. and Henen, B.T. 2007. Annual variation in the body condition of a small, arid-zone tortoise, Homopus signatus signatus. Journal of Arid Environments 71: 337-349.

Leuteritz, T.E.J. and Hofmeyr, M.D. 2007. The extended reproductive season of tent tortoises: a response to an arid and unpredictable environment. Journal of Arid Environments 68(4): 546-563.

Schumann, D.M., Bennett, N.C., Hofmeyr, M.D. and Cooper, H.M. 2006. Light induced Fos expression in the suprachiasmatic nucleus of the four‑striped field mouse, Rhabdomys pumilio, a southern African diurnal rodent. Brain Research Bulletin 70: 270-277.

Keswick, T., Henen, B.T. and Hofmeyr, M.D. 2006. Sexual disparity in activity patterns and time budgets of angulate tortoises (Chersina angulata) on Dassen Island, South Africa. African Zoology 41(2): 224-233.

Loehr, V.J.T., Henen, B.T. and Hofmeyr, M.D. 2006. Tick infestations in the Namaqualand speckled padloper, Homopus signatus signatus (Gmelin, 1789). African Zoology 41(2): 170-177.

Loehr, V.J.T., Henen, B.T. and Hofmeyr, M.D. 2006. Shell characteristics and sexual dimorphism in the Namaqualand speckled padloper, Homopus signatus signatus. African Journal of Herpetology 55(1): 1-11.

Horak, I.G., McKay, I.J., Henen, B.T., Hofmeyr, M.D., Heyne, H. and de Villiers, A.L. 2006. Parasites of domestic and wild animals in South Africa. XLVII. Ticks of tortoises and other reptiles. Onderstepoort Journal of Veterinary Research 73: 215-227.

Mann, G.K.H., O’Riain, M.J. and Hofmeyr, M.D. 2006. Shaping up to fight: sexual selection influences body shape and size in the fighting tortoise (Chersina angulata). Journal of Zoology London 269: 373-379.

Joshua, Q.I., Hofmeyr, M.D., Henen, B.T. and Weitz, F. 2005. Seasonal changes in the vegetation of island and mainland habitats of angulate tortoises in the Western Cape, South Africa. South African Journal of Science 101: 439-445.

Henen, B.T., Hofmeyr, M.D., Balsamo, R.A. and Weitz, F.M. 2005. Lessons from the food choices of the endangered geometric tortoise Psammobates geometricus. South African Journal of Science 101: 435-438.

Hofmeyr, M.D., Henen, B.T. and Loehr, V.J.T. 2005. Overcoming environmental and morphological constraints: egg size and pelvic kinesis in the smallest tortoise, Homopus signatus. Canadian Journal of Zoology 83(10): 1343-1352.

Schumann, D.M., Cooper, H.M., Hofmeyr, M.D. and Bennett, N.C. 2005. Circadian rhythm of locomotor activity in the four-striped field mouse, Rhabdomys pumilio: a diurnal African rodent. Physiology & Behavior 85: 231-239.

Hofmeyr, M.D. 2004. Egg production in Chersina angulata: an unusual pattern in a Mediterranean climate. Journal of Herpetology 38: 172-179.

Loehr, V., Henen, B.T. and Hofmeyr, M.D. 2004. Reproduction of the smallest tortoise, the Namaqualand speckled padloper, Homopus signatus signatus. Herpetologica 60(4): 44-54.

Balsamo Jr., R.A., Hofmeyr, M.D., Henen, B.T. and Bauer, A.M. 2004. Leaf biomechanics as a potential tool to predict feeding preferences of Psammobates geometricus (geometric tortoise). African Zoology 39(2): 175-181.

Henen, B.T. and Hofmeyr, M.D. 2003. Viewing chelonian reproductive ecology through acoustic windows: cranial and inguinal perspectives. Journal of Experimental Zoology 297A(1): 88-104.  

Lesia, M.G.A., Hofmeyr, M.D. and D’Amato, M.E. 2003. Genetic variation of three Chersina angulata (angulate tortoise) populations along the West Coast of South Africa. African Zoology 38(1): 109-117.

Ramsay, S.L., Hofmeyr, M.D. and Joshua, Q.I. 2002. Activity patterns of the angulate tortoise (Chersina angulata) on Dassen Island, South Africa. Journal of Herpetology 36(2): 161-169.