标题: Three-Toed Sloth’s Ecosystem [打印本页] 作者: choi 时间: 1-28-2014 09:49 标题: Three-Toed Sloth’s Ecosystem Nicholas Wade, The Sloth's Inner Life; An animal considered lazy has a lot going on under its fleece. New York Times, Jan 28, 2014. www.nytimes.com/2014/01/28/scien ... usy-inner-life.html
Quote:
"The sloth is not so much an animal as a walking ecosystem. This tightly fitting assemblage consists of a) the sloth, b) a species of moth that lives nowhere but in the sloth’s fleece and c) a dedicated species of algae that grows in special channels in the sloth’s grooved hairs.
"Every week or so, the [three-toed] sloth descends from its favorite [chocolate-producing cacao] tree to defecate. * * * The sloth is highly vulnerable on the ground and an easy prey * ** Its distant evolutionary cousin, the two-toed sloth, stays safely in the canopy [even to defecate]
Note:
(a) “sloth, which lives in the jungles of Central and South America”
sloth
en.wikipedia.org/wiki/Sloth
(they have very low metabolic rates (less than half of that expected for a mammal of their size), and maintain low body temperatures when active (30–34°C or 86–93°F), and still lower temperatures when resting; hangs upside down; “Almost all mammals have seven cervical vertebrae (neck bones), including those with very short necks, such as elephants or whales, and those with very long necks, such as giraffes). The few exceptions include manatees and two-toed sloths, which each have only six cervical vertebrae, and three-toed sloths with 9 cervical vertebrae”)
(b) The paper:
Pauli JN et al, A Syndrome of Mutualism Reinforces the Lifestyle of a Sloth. Proceedings of the Royal Society B, 281: _ (March 2014; online release before publication on Jan 22, 2014).
rspb.royalsocietypublishing.org/content/281/1778/20133006
* mutualism (biology)
en.wikipedia.org/wiki/Mutualism_(biology)
("a type of symbiosis. Symbiosis is a broad category, defined to include relationships that are mutualistic, parasitic, or commensal. Mutualism is only one type")
(c) “The descent to the sloth’s midden affords the pregnant moths in its fleece a chance to lay eggs.”
midden (n): “DUNGHILL” www.merriam-webster.com/dictionary/%20midden
(d) “After they die, their bodies are decomposed by the host of fungi and bacteria in the sloth’s fur. The metabolic products of this decay, especially nitrogen, are the feedstock for the specialist algae that grow in the sloth’s hair shafts.”
This “host” is not the one who holds a party (though that definition share the same etymology with the following definition).