Life Lines by Dr. Dolittle

Sponsored by the American Physiological Society

Extreme Animals

Researchers explore how the largest animals get enough to eat

Ever wonder how baleen whales (Mysticeta) get enough to eat? The mechanism is described for rorqual whales (Balaenopteridae) in a review article published this past October in Physiology. Researchers have found that rorqual whales (ex: blue whales and fin whales), in particular, have an interesting strategy for foraging. The process includes 5 steps that take place in rapid succession (about 20-90 sec total): quick forward lunges toward prey; opening their […]

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Tardigrades are not so tolerant after all

…at least when it comes to dealing with warming temperatures. In contrast to their reputation for being able to withstand almost any extreme environment (radiation, cold, drought, vaccuum of space), researchers at the University of Copenhagen have found that tardigrades may have an Achilles heal. They appear intolerant of sustained increases in temperature.  Study author Dr. Ricardo Neves was quoted in Science Daily, “The specimens used in this study were […]

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Final highlights from the 2019 Arizona Physiological Society conference

Here are some additional comparative physiology highlights from the 2019 Arizona Physiological Society poster session: Researchers at Arizona State University compared the physiology of Gambel’s quail (Callipepla gambelii) living in urbanized and less developed areas. They found that birds living in more urbanized areas were larger and had more circulating lipids than birds living in areas that were less developed. (A Funk, P Hutton, S Earl, P Deviche, and K Sweazea. […]

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Regenerating limbs…and heads

Mandy M. Schofield, Christian A. Okafor, and Jack D. Shepard from Towson University presented an interesting poster at the 6th annual Greater Washington DC Area Physiological Society on how planarians are a useful “Model Organism for Investigation and Education.” Planarians are indeed very interesting little animals. They have remarkable abilities to regenerate as shown in this YouTube video: Aside from this impressive ability and its application to limb regeneration, planaria […]

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New research on how treefrogs protect their cells during freezing

  Brian Stogsdill, Jim Frisbee and Dr. David Goldstein at Wright State University discussed their research at the 34th annual Ohio Physiological Society meeting on special water channels in the red blood cells of freeze-tolerant Cope’s gray treefrogs. These channels can shuttle both water and glycerol in and out of the cells to protect them from damage during freezing. Check out this video showing a treefrog waking up from a […]

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Adults are better adapted to survive without oxygen

Adult fruit flies (Drosophila melanogaster) are more tolerant of environments devoid of oxygen than their larvae. In fact, they are able to survive up to 12 hours without oxygen by becoming paralyzed, which enables them to dramatically reduce metabolism and the need for oxygen. In contrast, Drosophila larvae expend a lot of energy trying to escape and are only able to tolerate a couple of hours without oxygen. This is surprising […]

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Remarkable hypoxia and cold tolerance of rodents native to the Tibetan plateau

The plateau zokor (Eospalax baileyi) is an underground dwelling rodent species native to the Tibetan plateau (2000-4200 meters in elevation). A new study published in the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology explored how these animals were adapted to extract oxygen from an environment with very low levels (83-88% of atmospheric). Hemoglobin molecules found in red blood cells are responsible for binding oxygen and transporting it to tissues […]

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High altitude deer mice have less stress?

Animals that live at high altitude have evolved a number of physiological adaptations to deal with the low atmospheric oxygen concentrations (hypoxia). For low altitude acclimated animals, short exposures to high altitude results in activation of the sympathetic nervous system (i.e. the fight or flight response). This is a good thing because activation of this system results in more blood flow, especially to the heart and brain to help protect oxygen […]

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Animals that eat plastic?

Have you seen this? A video just released by Yellowstone National Park talks about how some heat-loving microorganisms can break down plastics. Pretty cool.   Not so cool was the recent finding published in the Proceedings of the Royal Society B: Biological Sciences that Astrangia poculata coral polyps are eating microplastics instead of brine shrimp eggs…on purpose. In the lab, the team were able to observe the corals consuming nearly […]

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Rapid switches in metabolism of hibernating animals

  In a new study published in the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology, researchers examined how changes in metabolism during torpor are regulated in 13-lined ground squirrels (Ictidomys tridecemlineatus). During hibernation, these animals cycle between bouts of torpor (about 2 weeks each) when their metabolism is reduced by 95% and body temperature can drop to 5degC and short states of interbout euthermia when both temperature […]

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