Word: bone
(lookup in dictionary)
(lookup stats)
Dates: all
Sort By: most recent first
(reverse)
...once radical notion that birds descended from dinosaurs--or may even be dinosaurs, the only living branch of the family that ruled the earth eons ago--has got stronger and stronger since paleontologists first started taking it seriously a couple of decades ago. Remarkable similarities in bone structure between dinos and birds were the first clue. Then came evidence, thanks to a series of astonishing discoveries in China's Liaoning province over the past five years, that some dinosaurs may have borne feathers. But a few scientists still argued that the link was weak; the bone similarities could...
...many biologists suspect that feathers originally arose to keep dinosaurs warm. The bone structure of dinosaurs shows that, unlike modern reptiles, they grew as fast as birds and mammals--which dovetails with a growing body of evidence that dinos were, in fact, warm-blooded. Says Padian: "They must have had a high basal metabolic rate to grow that fast. And I wouldn't be surprised if they had some sort of skin covering for insulation when they were small." Says Norell: "Even baby tyrannosaurs probably looked like this...
...stories in both her memoirs (a widely praised predecessor, Tender at the Bone: Growing Up at the Table, came out in 1998) are delicious reads: witty, reflective accounts of her experiences in, around and through food. They are perfectly balanced meals accompanied by recipes: the shrimp curry she cooks as a farewell to her Berkeley commune, the mushroom soup she makes to console her mother during a financial crisis, the lemon pasta Danny Kaye concocts for her when he reveals that he's a food-loving fellow traveler...
Each of these sources, however, is problematic. Bone marrow and the brain are difficult or painful to get to surgically. And cells from in-vitro embryos and aborted fetuses pose ethical and political problems. Indeed, President Bush is soon likely to make right-to-lifers happy by reimposing a ban on using federal funds for research on such tissues. (Another possible source of stem cells announced last week--the placentas of pregnant women--avoids these problems but hasn't been confirmed...
...cells, by contrast, are plentiful and easy to harvest--just ask anyone who has had liposuction. They are also rich in stem cells--not so surprising, in retrospect, since bone marrow and fat develop from the same embryonic tissue. Not only did the researchers get stem cells from liposuctioned human fat, they also made them grow into bone, muscle and cartilage cells--a sign that more ambitious tissue engineering is not out of the question...