Life Lines by Dr. Dolittle

Sponsored by the American Physiological Society

Extreme Animals

Extreme Physiology of Diving

Can you imagine what would happen to your body if you dove up to 1700 meters deep in the ocean for an hour and a half, or experienced months of food deprivation? In the case of deep diving, the high pressure causes the collapse of the lungs of terrestrial mammals (including humans!) and depletion of body oxygen stores, whereas long fasting periods compromise health and induce muscle wasting. Northern elephant […]

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Experimental Biology 2021: Q&A with Dr. Michael Tift and Anna Pearson

We are delighted to speak with Anna Pearson (MS student) and her mentor Dr. Michael Tift, Assistant Professor at the University of North Carolina – Wilmington. Anna presented her research “First report of red blood cell lifespan in a marine mammal: An insight into endogenous carbon monoxide (CO) production” at the 2021 Experimental Biology conference last month. What made you interested in studying red blood cells in dolphins?Dr. Tift became interested […]

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Experimental Biology 2021: Q&A with Dr. Christian Damsgaard

We are delighted to speak with Dr. Christian Damsgaard who is currently an Assistant Professor at the Aarhus Institute of Advanced Studies & Section for Zoophysiology, Aarhus University, Denmark. Dr. Damsgaard is a member of the Comparative and Evolutionary Physiology section of the American Physiological Society and he presented his research “Active Blood Acidification Greatly Enhances Oxygen Supply to the Teleost Retina” at the 2021 Experimental Biology conference today. What initially interested you in studying […]

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Surviving the cold

The ability to regulate body temperature is critical for animals. This is especially true for small mammals as they have a larger surface area resulting in more heat loss to the environment than larger animals. Animals that stay active during the winter likewise have to spend more energy to stay warm. To do this well, they need to balance heat loss with heat generation through shivering as well as non-shivering […]

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Extreme tolerance of dehydration stress

Talk about an extreme animal. During the rainy season annual killifish, Austrofundulus limnaeus, lay eggs that are resistant to droughts. This is an important attribute for a fish that lives in temporary pools of water. The stress-resistant embryos within the eggs literally shut down their metabolism to survive months – possibly years without water. For many fish, exposure to air (and oxygen) can cause profound oxidative stress. Remarkably, this is […]

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Scientists discover gene that may protect from hypertension

Giraffes are extreme. Given their long necks, their blood pressure is 2.5 times higher than ours, which ensures that oxygenated blood makes it all the way up to their head. Having high blood pressure, however, is simply a normal characteristic of being a giraffe. A new study published in Science Advances explored the giraffe genome to identify genes that might help protect the cardiovascular system of giraffes by comparing their […]

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Anoxia tolerance in goldfish

The reason mammals are not very good at tolerating hypoxic (i.e. low oxygen) environments, is because the brain relies heavily on oxygen for metabolism. It is so stingy, it uses about 20% of the oxygen in the body to make ATP. Without oxygen, the brain has to rely on glycolysis to make ATP and this process is not good at meeting the energy requirements of the neurons, ultimately resulting in […]

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Metabolic costs of reproduction, eating, and increasing temperatures

Planarians are rather cute little flatworms, although they tend to wreak havoc in fish tanks. Researchers have long been fascinated by their ability to regenerate body parts when injured with the help of adult stem cells. More recently, they have gained attention for their ability to survive long periods of time without eating by “degrowing”, i.e. getting smaller but still keeping their shape and functions intact. I would shrink too […]

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How exercise training and diet may impact exercise performance

Both diet and exercise training are associated with muscle performance and endurance. Migratory birds undergo intense endurance exercise. In fact, a recent review indicated that flapping flight costs more energy (9 x increase from basal metabolic rate) than required by elite athletes competing in the Tour de France (4.3 x increase from basal metabolic rate) (Butler, 2016). Unlike running animals, migratory birds fuel endurance exercise with fats as opposed to […]

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