Life Lines by Dr. Dolittle

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Hibernation and Hypoxia

Hummingbirds can choose how deep to sleep

Could you imagine drinking a can of soda every minute just to support your high metabolism? Amazingly, that is the equivalent to how much sugar a hummingbird needs to support their rapid wingbeats during flight. In fact, hummingbird flight muscles are the fastest on record, allowing the birds to flap their wings at a rate of up to 200 beats per second! That explains why they are always at my […]

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Hypoxia gives alligators a big heart: Q&A with Dr. Dane Crossley, University of North Texas

We recently interviewed Dr. Dane Crossley, Professor of Physiology in the College of Biological Sciences at the University of North Texas about the research his laboratory presented at the recent APS Intersociety meeting, Comparative Physiology: From Organisms to Omics in an Uncertain World. The title of his presentation was, “A large heart: How does developmental hypoxia affect individual cardiomyocyte performance in the American alligator, Alligator mississippiensis.” Thank you for taking time […]

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It’s getting cold outside…what’s a squirrel to do?

As the weather cools down, animals must find ways to stay warm. This is especially important for small animals as they lose body heat faster than larger animals. One way to stay warm is by increasing your metabolism to create body heat, although this process requires a lot of energy. That can be a problem in areas where food may be scarce in the winter. Although some animals, like the […]

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Life at the top

Moving to high altitude requires a bit of an adjustment. One of the ways our bodies adjust to the low levels of oxygen is by making more red blood cells, which are responsible for transporting oxygen in the body. More red blood cells means that our blood can pick up more oxygen. If this process continues unchecked, however, it can lead to chronic mountain sickness, also known as Monge’s Disease. […]

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Chronic stress during pregnancy increases risk of stillbirth and preterm delivery

At the end of pregnancy, levels of the hormone oxytocin increase to stimulate parturition, or childbirth. The stress hormone cortisol is also important for normal fetal development and, like oxytocin, cortisol increases at the end of pregnancy. This may help explain why chronic stress during pregnancy increases the risk of complications such as stillbirth.   A new study published in the American Journal of Physiology – Regulatory, Integrative and Comparative […]

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Turning up the heat

There are several ways to stay warm on a cold day. If you are human, you can turn up the heat in your home, put on a sweater, snuggle, and even produce body heat through shivering as well as non-shivering metabolic pathways – although the ability to produce heat metabolically typically declines with aging. If you are a small mammal, turning up the heat or putting on a sweater are […]

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Nitrites and noses

If you have ever had a fish tank, you may be familiar with monitoring ammonia levels in the water. Ammonia levels can rise due to overcrowding, overfeeding, as well as fish waste. Nitrite levels in the water also require monitoring as nitrite can bind to hemoglobin, which prevents oxygen from binding. In effect, by preventing oxygen from binding, the fish can succumb to hypoxia. Hannah Hughes, a graduate student working […]

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EB 2022: Seals, seals, and more seals

Several posters at EB 2022 in Philadelphia this month were focused on understanding the remarkable physiology of diving seals. Although we may think of the image below when we picture seals, they really are quite the athletes in water. Kaitlin Allen (a graduate student working in the laboratory of Dr. José Pablo Vázquez-Medina at the University of California Berkeley) presented her research on Northern elephant seals and how these animals […]

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EB2022: Facing Oxygen Challenges

I learned a lot about how animals adapt to changing environmental oxygen levels in the Experimental Biology symposium on “Functional Integration across the Oxygen Cascade in the Face of Challenging Environments.” Here is what I learned… The first presenter, Dr. Lara do Amaral-Silva (postdoctoral fellow at the University of North Carolina at Greensboro working with Dr. Joseph (Joe) Santin), spoke about her research on adaptations in the bullfrog “super-brain” that […]

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Stranger than science fiction: treefrogs that freeze and live to tell the story

Today we have a guest blog written by Elizabeth Evans (pictured above), a graduate student at the University of Dayton working in the laboratory of Dr. Carissa Krane. She presented her research on freeze tolerance today at the 2022 Experimental Biology conference in Philadelphia. She wrote the award-winning blog entry below which earned the 2022 Dr. Dolittle Travel Award to attend the conference. Congratulations Elizabeth!! Stranger than science fiction: treefrogs […]

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