Cosima Porteus

Assistant Professor



CSB Appointment


Research Areas

Animal Biology, Physiology


Ph.D University of British Columbia 2012
MSc University of Guelph 2006
BSc University of Guelph 2004

Primary Undergraduate Department

UTSC Biological Sciences

Graduate Programs

Cell Systems and Biology

Research Description

The focus of our laboratory is to understand how fish sense, interact with and respond to their environment, linking environmental changes or challenges to whole animal physiology, behaviour and ecology. Our current focus is on anthropogenic factors as these have contributed significantly to an increase in greenhouse gas emissions, including carbon dioxide (CO2). The amount of CO2 in the atmosphere has increased in the last 100 years and it is predicted that it will continue to do so in a business as usual scenario. The oceans absorb about a quarter of the total carbon dioxide released into the atmosphere and this consequently leads to ocean acidification. Additionally, sea surface temperatures are also increasing as a consequence of climate change. We are currently using a combination of techniques including in vivo physiology, cellular imaging, high through-put sequencing, immunohistochemistry, and nerve recording, in combination with behaviour experiments to gain a better understanding of the fundamental mechanisms that allow aquatic animals to respond to environmental stressors. We have recently shown that elevated carbon dioxide affects the olfactory system of European sea bass (Porteus et al 2018, Nature Climate Change). These findings have far-reaching impacts and applications from marine conservation to commercial and recreational fisheries. The current research in our lab is investigating the effect of multiple stressors on the olfactory pathways in fish.

Contact Information

Office Phone: 416-287-7413
Lab: SW435

Mailing Address

Department of Cell & Systems Biology
University of Toronto
1265 Military Trail
Scarborough, ON M1C 1A4

Visit lab’s website



New insights into organ-specific oxidative stress mechanisms using a novel biosensor zebrafish

Mourabit S, Fitzgerald JA, Ellis RP, Takesono A, Porteus CS, Trznadel M, Metz J, Winter MJ, Kudoh T, Tyler CR
2019, Environment International, 10.1016/j.envint.2019.105138

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Near-future CO2 levels impair the olfactory system of a marine fish

Porteus CS, Hubbard PC, Uren Webster TM, van Aerle R, Canário AVM, Santos EM, Wilson RW
2018, Nature Climate Change, 10.1038/s41558-018-0224-8

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Combined impacts of elevated CO2 and anthropogenic noise on European sea bass (Dicentrarchus labrax)

Poulton DA, Porteus CS, Simpson SD, Juanes F
2016, ICES Journal of Marine Science, 10.1093/icesjms/fsw003

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An emerging role for gasotransmitters in the control of breathing and ionic regulation in fish

Perry S, Kumai Y, Porteus CS, Tzaneva V, Kwong RWM
2015, Journal of Comparative Physiology B, 10.1007/s00360-015-0949-x

A role for nitric oxide in the control of breathing in zebrafish (Danio rerio)

Porteus CS, Pollack J, Tzaneva V, Kwong RWM, Kumai Y, Abdallah SJ, Zaccone G, Lauriano ER, Milsom WK, Perry SF
2015, Journal of Experimental Biology, 10.1242/jeb.127795

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Time domains of the hypoxic cardio-respiratory response in bowfin (Amia calva)

Porteus CS, Wright PA, Milsom WK
2014, Respiratory Physiology & Neurobiology, 10.1016/j.resp.2013.12.013

Hydrogen sulfide inhibits Na+ uptake in larval zebrafish, Danio rerio

Kumai Y, Porteus CS, Kwong RWM, Perry SF
2014, Pflügers Archiv - European Journal of Physiology, 10.1007/s00424-014-1550-y

Characterisation of putative oxygen chemoreceptors in bowfin (Amia calva)

Porteus CS, Wright PA, Milsom WK
2014, Journal of Experimental Biology, 10.1242/jeb.098467

The role of hydrogen sulphide in the control of breathing in hypoxic zebrafish (Danio rerio)

Porteus CS, Abdallah SJ, Pollack J, Kumai Y, Kwong RWM, Yew HM, Milsom WK, Perry SF
2014, The Journal of Physiology, 10.1113/jphysiol.2014.271098

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The effect of sustained hypoxia on the cardio-respiratory response of bowfinAmia calva: implications for changes in the oxygen transport system

Porteus CS, Wright PA, Milsom WK
2013, Journal of Fish Biology, 10.1111/jfb.12186

Distribution of acetylcholine and catecholamines in fish gills and their potential roles in the hypoxic ventilatory response

Porteus CS, Brink DL, Coolidge EH, Fong AY, Milsom WK
2013, Acta Histochemica, 10.1016/j.acthis.2012.06.004

Serotonin directly stimulates cortisol secretion from the interrenals in goldfish

Lim JE, Porteus CS, Bernier NJ
2013, General and Comparative Endocrinology, 10.1016/j.ygcen.2013.08.008

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Acid Water Interferes with Salamander–Green Algae Symbiosis during Early Embryonic Development

Bianchini K, Tattersall GJ, Sashaw J, Porteus CS, Wright PA
2012, Physiological and Biochemical Zoology, 10.1086/667407

Neurotransmitter profiles in fish gills: Putative gill oxygen chemoreceptors

Porteus CS, Brink DL, Milsom WK
2012, Respiratory Physiology & Neurobiology, 10.1016/j.resp.2012.06.019

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Time domains of the hypoxic ventilatory response in ectothermic vertebrates

Porteus C, Hedrick MS, Hicks JW, Wang T, Milsom WK
2011, Journal of Comparative Physiology B, 10.1007/s00360-011-0554-6

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A comparative analysis of putative oxygen-sensing cells in the fish gill

Coolidge EH, Ciuhandu CS, Milsom WK
2008, Journal of Experimental Biology, 10.1242/jeb.015248

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Parameters influencing the dissolved oxygen in the boundary layer of rainbow trout (Oncorhynchus mykiss) embryos and larvae

Ciuhandu CS, Wright PA, Goldberg JI, Stevens ED
2007, Journal of Experimental Biology, 10.1242/jeb.02754

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The effect of oxygen on the growth of Oncorhynchus mykiss embryos with and without a chorion

Ciuhandu CS, Stevens ED, Wright PA
2005, Journal of Fish Biology, 10.1111/j.1095-8649.2005.00856.x

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