Life Lines by Dr. Dolittle

Sponsored by the American Physiological Society

Reproduction and Development

Dwarfism documented for first time in wild giraffes

A disorder affecting the normal development of cartilage and bone has been observed in wild giraffes. While skeletal dysplasia, or dwarfism, has been observed in captive and domestic animals such as dogs, cows, rats, pigs and marmosets, it is not often seen in wild animals. In a new study, researchers used photography to document the condition for the first time in a wild Nubian giraffe calf (Giraffa camelopardalis camelopardalis) in […]

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Long sperm, short sperm, fast sperm, slow sperm

I read an interesting review published in Physiology that examined how sperm from different species are especially evolved to help promote fertilization, which if successful, results in the creation of an offspring. It is simply amazing to think of the multitude of ways this process occurs in nature. Take marine invertebrates and fish for example. These animals release eggs and sperm into the water. In contrast, fertilization happens internally in […]

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Live fast, die young

Researchers have long known that smaller animals have higher metabolisms and tend to die younger than larger animals. Think about it – a mouse typically only lives about 2 years whereas an elephant in the wild may live 50-70 years, depending on the species. After studying over 700 species of birds and 540 species of mammals, scientists discovered that migratory animals also live faster (mature and reproduce earlier) and die […]

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How a really long winter’s nap can impact sperm production

As winter approaches, hibernating animals will finalize their preparations for taking a ‘long winter’s nap’. These remarkable animals reduce their metabolism to help conserve energy at a time when environmental resources are scarce and considerable energy would otherwise need to be spent on just staying warm. For many species of hibernators, periodically entering this state of torpor allows them to reduce their energy needs by 90% compared to intermittent states […]

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How some fish may compensate for low environmental oxygen

     Adult fish rely on gills to extract oxygen from the surrounding water. Larval fish, on the other hand, do not have well-developed gills and instead rely primarily on gas exchange across their skin.      In a new study published in the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology, researchers examined whether larval fish could use their pectoral fins to increase the flow of water […]

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Researchers explore why fetuses that experienced intrauterine growth restriction have smaller muscles

We have talked several times about the long-lasting issues related to growth restriction of a fetus during pregnancy: Intrauterine growth restriction increases risk of cardiovascular disease as adults Intrauterine growth restriction increases risk of insulin resistance as adults It can also result in offspring that have smaller muscles. New research published in the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology suggests this may be due to adaptations to […]

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On the path to understanding the effects of white-nose syndrome

Molly Simonis and colleagues from Wright State University and Ohio University presented interesting research at the 34th annual Ohio Physiological Society conference on their work looking at the physiological effects of exposure to white-nose syndrome. White-nose syndrome is caused by the fungus Pseudogymnoascus destructans and has been blamed for killing millions of bats in North America. This new study seeks to examine whether pregnant female Eptesicus fuscus bats, a species less susceptible to […]

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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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Don’t feed the birds – urban crows have higher cholesterol

If you have ever been to a fast food restaurant, you may have noticed that people are not the only consumers of fast food. In fact, some species of birds are known to frequent fast food chains where they can get a quick meal of food leftover or intentionally dropped by customers. While people may delight in tossing our feathered friends a french fry on occasion, a new study published […]

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Editor’s picks for 2018

The Editor’s Picks for 2018 have been released for the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology. According to the editorial team, the focus of this journal is on “the regulation of whole organismal function that requires the interplay of multiple organ and tissue systems.” The top comparative physiology articles of 2018 included: An article by Hersh et al., who provided evidence that little skates may be useful […]

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