User:Kegseminar

Kirsten Gallagher

Seminar in Physiology UWO Winter 2012

Article options for review

My first choice for an article to review and update is the Puerto Rican Crested Toad. This page is entirely lacking of the life history of the animal, for which I am familiar, as well as physiology, research status and conservation efforts. I believe that I could greatly improve this article by providing thorough information on all four of these aspects, providing the public with more information about this critically endangered species.

My second choice for article review is Metabolic water. There is very little information, besides the basics, provided in this article, and I believe through a more thorough description and examples of animals that use this physiological process the article could be improved.

My third choice is the Thirteen-lined ground squirrel. This article mentions hibernation, but is lacking any physiology information on this species. This article is also in desperate need of citations for most of the information given.

The last article in my list for review is the Oryx. This article provides information about the status of the species, and briefly mentions the fact that they can survive for months at a time without water, but it does not address this topic further. Since I think the Oryx's ability to use metabolic water and preformed water for survival is really cool and interesting, I think it would be valuable to include this information with the article of this species.

All of these sound good, though the Oryx and metabolic water link nicely..go for it! Milligancl (talk)

Oryx Article Edits

Article to review: Oryx

The article on the Oryx primarily serves to describe the species distribution and conservation status, but with no real mention of any of its life history traits or physiological adaptations to its environment. This article has only a very basic overview of the status of each species and their distribution. This information is useful, but could use further expansion and better explanations as to why some of these species are extinct in the wild. It is also greatly lacking in life history information, with only brief mentioning of newborns and some information of these species’ horns.

There are many improvements that could be made to this article, however I am going to focus on the lack of information provided on the physiological mechanisms of water conservation in these species’.Though this Wiki article has one sentence explaining that this species can survive long periods without drinking water, the article does not address this fact any further. The article currently neither defines “long periods” nor explains how this species is able to survive without water for extended periods. Since the Oryx has become one of the prime examples of animals that can survive in extremely arid environments without water, I believe that this aspect of the Oryx’s physiology should be addressed. By explaining the physiological mechanisms utilized by these species for water conservation, the statement that they can survive for long periods without drinking water will be supported. By addressing this aspect of the Oryx’s physiology, the public will also gain a better understanding of the extremity of this species’ ability to adapt and survive.

There are three resources that I believe would be beneficial for this article’s improvement:

Ostrowski et al. 2003 addresses the heat loading ability and use of heat loading in the Arabian Oryx to deal with both heat stress and water conservation. Some key points from this article that could improve the Wiki page include:

• These animals deal with high heat loading by using regional heterothermia.
• This heterothermia helps them reduce the amount of water they need to use for thermoregulation.
• If they did not use heterothermia, these animals would need to increase their water intake by up to 19%, which in their extreme arid habitats is not generally feasible.
• They also have a very low water turn-over rate for animals their size, which also improves water conservation.

Williams et al. 2001 measured both the field metabolic rates and water flux rates of free-living and captive Arabian Oryxs. This article serves to address the ways that the oryx deals with water conservation in its environment, and has a good explanation of how they deal with no free standing water. Some key points include:

• The Oryx is one of the largest ungulates to survive in arid and hyper-arid environments.
• These animals face the major problem of meeting their water requirements and maintaining water balance in an environment where there generally is no free standing water present.
• The Oryx manages without free standing water by using metabolic water, preformed water in its food, and behaviourally timing foraging to times of day when the water content is highest in the plants. This foraging timing allows the Oryx to gain as much water as possible from its food.

Ostrowski et al 2006 tested the physiological changes in water conservation and metabolic rate to food and water restriction in a captive set of Oryxs. This paper provides good information including key points:

• These animals have the challenge of not being able to escape the heat of the day like other desert mammals, which for example spend much of the day in burrows to escape the heat. The Oryx instead spends the hottest parts of the day completely inactive under the shade of trees, if they can find it.
• The Oryx only has access to free standing water for extremely short periods of time following a rain, which can occur 4-6 months apart, if at all.
• The Oryx is able to decrease its resting metabolic rate during the hottest and driest parts of the year, decreasing the amount of water they must use in metabolism, therefore conserving water.
• They also respond to decreased water availability by decreasing their evaporative water loss, creating drier feces, and increasing their urine concentrating ability.

Ostrowski, S., Williams, J.B., Mesochina, P. and Sauerwein, H. (2006) Physiological acclimation of a desert antelope, Arabian Oryx (Oryx leucoryx), to long-term food and water restriction. Journal of Comparative Physiology B 179: 191-201

Ostrowski, S., Williams, J.B. and Ismael, K. (2003) Heterothermy and the water economy of free-living Arabian Oryx (Oryx leucoryx). The Journal of Experimental Biology 206:1471-1478

Williams, L.B., Ostrowski, S., Bedin, E. and Ismael, K. (2001) Seasonal variation in energy expenditure, water flux and food consumption of Arabian Oryx (Oryx leucoryx). The Journal of Experimental Biology 204: 2301-2311