Life Lines by Dr. Dolittle

Sponsored by the American Physiological Society

Environment

Birds may stay warm with the help of red blood cells

Researchers at Lund University in Sweden were interested in understanding how birds adapted to cold weather. Birds can’t turn up the heat in their birdhouse, so it is important for them to find physiological ways to stay warm. While they can store body fat and grow more feathers for insulation, metabolism is the primary way endothermic animals create body heat. Mitochondria produce cellular energy (ATP) but can also create heat […]

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Shape-shifting animals adapting to climate change

A recent review of the existing scientific literature found evidence suggesting that warm-blooded animals may be literally shape-shifting to adapt to climate changes. According to Allen’s rule, animals living in warmer climates have larger appendages than those living in cold climates, which helps increase the available surface area for heat loss to the environment. Such heat exchange mechanisms are very important in thermoregulation to avoid retaining excess heat. The authors […]

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Tenrecs may shed light on the evolution of body temperature regulation

The common tenrec (Tenrec ecaudatus) just may be a living representative of ancestral placental mammals and they are very interesting when it comes to body temperature regulation and torpor. Torpor is a complex series of physiological changes that reduce an animal’s physical activity as well as heart, breathing and metabolic rates, which also results in decreases in body temperature than can be as low as their surrounding environment. Many mammalian […]

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High altitude survival and adaptation

Life at high altitude presents unique physiological challenges for organisms that were explored in a recent review published in the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology. For placental mammals, offspring born at high altitude (>2500 m above sea level) typically weigh less at birth compared to lowland animals. Fetal growth restriction is problematic as it is associated with long-term health risks and reduced survival. It is […]

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Oddity of mammalian red blood cells

Mammalian red blood cells do not have a nucleus, which is different from birds, amphibians, reptiles, and fish (see image above). Many textbooks report that the absence of a nucleus provides room for more hemoglobin within the cells, which is important to fuel the relatively high metabolic rates of mammals. Hemoglobin is an important oxygen-binding molecule that allows the red blood cells to transport oxygen to tissues throughout the body […]

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Don’t feed the birds: help stop the spread of a deadly illness

The USGS is investigating a mysterious illness that has resulted in numerous reports of sick or dying birds with crusty swollen eyes (even blindness) and neurological effects such as tremors, inability to stand, and lethargy. The majority of affected birds are juvenile. The illness is rather widespread with reports of sick birds in Washington DC, Maryland, Virginia, West Virginia, Kentucky, Delaware, New Jersey, Pennsylvania, Ohio, and Indiana. Since May, diagnostic […]

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What can hibernators teach us about obesity? Q&A with Dr. Courtney Kurtz, University of Wisconsin

We are pleased to talk with Dr. Courtney Kurtz, Associate Professor of Biology at the University of Wisconsin, Oshkosh about her research on hibernation and how her research might lead to treatments for obesity. Ground squirrels are a natural model organism for many physiological processes. Can you tell us why you use ground squirrels in your research?  ​Ground squirrels are hibernators.  They spend the majority of the winter in a […]

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Can lobsters lead us to the proverbial ‘Fountain of Youth’?

When thinking about lobsters, some people may think of: Aside from being a favorite menu item, did you know that American lobsters (Homarus americanus) are one of the largest bottom dwelling (i.e. benthic) invertebrate in the ocean? In fact, they seem to be able to grow indefinitely and have been observed to reach over 1 meter in length? For this reason, scientists suspect they may be a rather long-lived species […]

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Bioaccumulation of metals in sharks

A new study highlights the impact of metal accumulation (cobalt, manganese, nickel, copper, iron and mercury) on the health of twenty individual sharks representing 8 species that were accidentally caught by fisheries in Brazil. Necropsies of the animals showed high levels of metals in the liver, gills and rectal glands. Perhaps not surprisingly, larger animals had more accumulation of the metals in their gills than smaller animals. Higher accumulation in […]

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A whale shark’s superpower: Healing

Da-dum, da-dum…that’s right! Shark week is back!! It starts tonight on Discovery channel. Grab some popcorn, it’s going to be a wild ride! To kick off the week in our own way, I found this interesting study that examined wound healing in whale sharks, the world’s largest fish. These animals often exhibit scars resulting from collisions with boats and new research shows they have impressive wound healing capabilities. In the […]

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