Posted on 01/03/2007 10:04:31 AM PST by SunkenCiv
The sauropod dinosaurs were the largest land creatures ever, with some specimens tipping the scales at up to 60,000 pounds.
They were vegetarians, however, and scientists have long wondered how they could have eaten enough to grow so big. They had small heads and pointy teeth, ill-suited to mashing up the large quantities of vegetation needed. So some scientists have suggested that the dinosaurs must have swallowed stones and used them to grind up the food, much the way modern birds do in their gizzards. Such stones, or gastroliths, have been found in fossil sauropods.
But a new study by Oliver Wings and P. Martin Sander of the University of Bonn in Germany makes the case that these fossil gastroliths were not part of any dinosaur food mill.
(Excerpt) Read more at nytimes.com ...
No gastric mill in sauropod dinosaurs:Polished pebbles occasionally found within skeletons of giant herbivorous sauropod dinosaurs are very likely to be gastroliths (stomach stones). Here, we show that based on feeding experiments with ostriches and comparative data for relative gastrolith mass in birds, sauropod gastroliths do not represent the remains of an avian-style gastric mill. Feeding experiments with farm ostriches showed that bird gastroliths experience fast abrasion in the gizzard and do not develop a polish. Relative gastrolith mass in sauropods (gastrolith mass much less than 0.1% of body mass) is at least an order of magnitude less than that in ostriches and other herbivorous birds (gastrolith mass approximates 1% of body mass), also arguing against the presence of a gastric mill in sauropods. Sauropod dinosaurs possibly compensated for their limited oral processing and gastric trituration capabilities by greatly increasing food retention time in the digestive system. Gastrolith clusters of some derived theropod dinosaurs (oviraptorosaurs and ornithomimosaurs) compare well with those of birds, suggesting that the gastric mill evolved in the avian stem lineage.
new evidence from analysis of
gastrolith mass and function in ostriches
Oliver Wings and
P. Martin Sander
Proceedings of the Royal Society B: Biological Sciences
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Warm-Blooded Dinosaurs?
http://biology.fullerton.edu/biol404/hol/hol_ch13.html
I'm thinking we just don't want to go there.
I don't want to give the NYT the hits. Where do squirrels come in?
Any opening bigger than 2 inches.
;')
I was reminded of Mom's cow magnets by this article. Mom's magnets were never used in a cow & were around the house only as a novelty.
Cow magnets are popular with dairy farmers and veterinarians to help prevent Hardware Disease in cattle. While grazing, cows eat everything from grass and dirt to nails, staples and bits of bailing wire (referred to as tramp iron). Tramp iron tends to lodge in the honeycombed walls of the reticulum, threatening the surrounding vital organs and causing irritation and inflammation, known as Hardware Disease. The cow loses her appetite and decreases milk output (dairy cows), or her ability to gain weight (feeder stock). Cow magnets help prevent this disease by attracting stray metal from the folds and crevices of the rumen and reticulum. One magnet works for the life of the cow!
http://www.magnetsource.com/Solutions_Pages/cowmags.html
I guess that explains why eating beef is good for iron deficiency... [rimshot!]
Psychic Psquirrel Ping.
Is there anything you can tell us about the [ahem] stones?
That's kinda weird... one nut, two heads...
...nothin' eh? Tough room.
"Squirrels That Predict the Future" was the article title, but it was about more than one thing. The squirrel news had already been posted from another source, and frankly, it wasn't too interesting.
Tough room?
YOu think this is tough, just try the Squirrel Flambe!
I'll be here all next week...
[rimshot!]
:'D
Reminds of the Jedi Squirrels pic. Think they use the Force to predict the future?
FOFLMAO!
well this was completely different..
you learn something new every day.
s/b:
SquirrelKing: "Tail me something I don't know."
[rimshot!]
LOL!
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