Mery Martinez Garcia

Research

My research interests primarily focus on animal physiology, specifically on the variations in physiological traits and adaptive mechanisms that allow animals to survive in changing environments. My students and I prefer to combine physiological, biochemical, behavioural, and ecological data to examine how the energetic metabolism in animals is affected when abiotic or biotic factors in their environments change. At the moment, my work is mainly focused on fish, but I am equally interested in vertebrates in general. My previous research included studying the physiology of locomotion in fish and their response to food availability. Recently, we have been focusing on the widespread phenomenon of hypoxia and its effects on fish fitness. We studied the reproductive fitness of three African fish species: Barbus neumayeri, Pseudocrenilabrus multicolor victoriae, and Barbus apleurogramma. My students and I have been investigating the extent to which hypoxia can affect reproductive fitness (gonad size, sperm morphometry, and sperm swimming capacity) across sites with varying dissolved oxygen levels (hypoxia vs. normoxia).

Over the last couple of years, my students and I have focused our attention on fish that use electric signals and investigate their physiological responses to environmental change. In collaboration with Dr. Luis Fernando DeLeón, University of Boston at Massachusetts, we are studying whether trade-offs exist between life history traits and reproductive fitness in the electric fish Brachyhypopomus occidentalis from Panama. This amazing fish uses electric pulses produced by a specialized type of muscle for intra and inter specific communication; however, little its known about the cost of electric signal communication and reprodution. In collaboration with Dr. Gillian Renshaw, Griffith University in Australia, we are studying the potential effects of global warming on the embryological development of two species of sharks: the Eppaulette Shark (Hemiscyllium ocellatum) and the Grey Carpet Shark (Chiloscyllium punctatum). Although most fish living in reef platforms are capable of avoiding the severe decrease in dissolved oxygen as well as the elevated temperatures during day time low tides, sessile shark embryos enclosed in egg cases are not able to escape these exposures.  Recent studies have shown that early developmental stages are highly vulnerable to predation, elevated CO2, temperature changes as well as low dissolved oxygen.  However, it not clear yet if the capacity of sharks to adapt to the currently rapid anthropomorphic environmental changes is compromised during early stages of development.  Hence, we aim to further our understanding of the impact that global warming could pose for the survival and development of shark embryos within their egg cases.

Awards

• 2015                             Laurentian University Students Teaching Award
  
• 1997 – 2000             Ph.D. Bourse d’excellence. Québec Government. Canada.
  
• 1999                            Travel fellowship. International Congress of Comparative Physiology and Biochemistry ($500).
  
• 1996 – 1997             Ph.D. Bourse d’exemption des frais de scolarité for Ph.D. Québec Government. Canada.
  
• 1995 – 2001             M.Sc and Ph.D. Bourse de soutien from Biology Department, Laval University, Québec, Québec.
  
• 1994 – 1996             M.Sc. Bourse d’exemption des frais de scolarité for my master’s. Québec Gouverment. Canada.
  
• 1994 – 1996             M.Sc ICETEX-Colombia $7000 USD/ year; for 2 years.
  

Teaching

• BIOL 5786 E Topics in Vertebrate Physiology
• BIOL 4736 E Developmental Biology 3 cr. (taught every other year)
• BIOL 4736 F Biologie du Développement 3 cr. (taught every other year)
• BIOL 3756 E Vertebrate Physiology 3 cr. (taught every other year)
• BIOL 3756 F Physiologie des Vertébrés 3 cr. (taught every other year)
• BIOL 3327 F Méthodes Expérimentales 3 cr. (taught every year)
• BIOL 2105 F Anatomie et Physiologie Humaine 6 cr (taught every year)
• BIOL 1507 F Biologie II

Publications

• Mahamat, M., L. F. De Leon and M. L. Martinez. (2023). Exploring potential drivers of brain size variation in the electric fish Brachyhypopomus occidentalis. Zoology 156. DOI: 10.1016/j.zool.2022.126058.
• Martínez, M.L., Mullin, V. and Schulte-Hostedde A. (2015). Variation in sperm morphometry of the African cyprinid Barbus neumayeri. Canadian Journal of Zoology 93: 259-266.
• Crocker C. D., Chapman, L.J. and Martínez, M.L. (2013). Hypoxia-induced plasticity in the metabolic response of a widespread cichlid. Comparative Biochemistry and Physiology, Part B 166: 141-147.
• Harniman Robert, Thomas J. S. Merritt, Lauren J. Chapman, David Lesbarrères and Mery L. Martinez. (2013). Population differentiation of the African cyprinid Barbus neumayeri across dissolved oxygen regimes. Ecology and Evolution 3(6): 1495–1506.
• Crocker C. D., Chapman, L.J. and Martínez, M.L. (2013) Natural variation in enzyme activity of the African cichlid Pseudocrenilabrus multicolor victoriae.  Comparative Biochemistry and Physiology, Part B 164, pp. 53-60 DOI information: 10.1016/j.cbpb.2012.10.003
• Martínez, M.L, Raynard ,E., Rees, B.B. and Chapman, L.J.. (2011). Oxygen limitation and tissue metabolic potential of the African fish Barbus neumayeri: roles of native habitat and acclimatization. BMC Ecology 11(1): 2.
• Martínez, M.L, Chapman, L.J., and Rees, B.B. (2009).  Population variation in hypoxic responses of the cichlid Pseudocrenilabrus multicolour victoriae. Canadian Journal of Zoology 87:188-194.
• Carreau, N.D., Mirza, R. S., Martínez M.L. and Pyle G.G. (2008).  The ontogeny of chemically-mediated antipredator responses of fathead minnows (Pimephales promelas). The Journal of Fish Biology 73: 2390-2401
• Martínez, M., Landry, C., Boehm, R., Manning, S., Cheek A. O., and Rees, B.B. (2006).  Effects of long-term hypoxia on enzymes of carbohydrate metabolism in the Gulf killifish, Fundulus grandis. The Journal of Experimental Biology 209: 3851-3861.
• Martínez, M., Bédard, M., Dutil, J.-D. and Guderley, H. (2004).  Does condition of Atlantic cod (Gadus morhua) have a greater impact upon swimming performance at Ucrit or Sprint speeds?. The Journal of Experimental Biology 207: 2979-2990.
•  Martínez, M., Chapman, L.J., Grady, J. and Rees, B.B. (2004).  Interdemic variation in hematocrit and lactate dehydrogenase in the African cyprinid Barbus neumayeri. The Journal of Fish Biology 65: 1056-1069.
•  Martínez, M., Guderley, H., Dutil, J.-D., Winger, P.D., He, P. and Walsh, S.J. (2003).  Condition, prolonged swimming performance and muscle metabolic capacities of cod (Gadus morhua). The Journal of Experimental Biology.  206:503-511.
• Martínez, M., Guderley, H., Nelson, J.A., Webber, D. and Dutil, J.-D. (2002).  Once a fast cod, always a fast cod: maintenance of performance hierarchies through changing food availability in cod (Gadus morhua).  Physiological and Biochemical Zoology.  75: 90-100.
• Martínez, M., Dutil, J.-D. and Guderley, H. (2000).  Longitudinal and allometric variation in indicators of muscle metabolic capacities in Atlantic cod (Gadus morhua). Journal of Experimental Zoology  Vol. 287: 38-45.
• Martínez, M., Couture, P. and Guderley, H. (1999).  Temporal changes in tissue metabolic capacities of wild Atlantic cod Gadus morhua (L.) from Newfoundland. Fish Physiology and Biochemistry  20: 181-191.