Tag Archives: felisa smith

Were Dinosaurs Cold-Blooded or Warm-Blooded? Neither, Study Finds

A study that originated in the lab of UA biologist Brian J. Enquist with UA alum John Grady suggests dinosaurs had a metabolism that was neither warm- nor cold-blooded, but somewhere in between.

Dinosaurs dominated the Earth for more than 100 million years, but all that remains today are bones. This has made it difficult to solve a long-standing and contentious puzzle: Were dinosaurs cold-blooded animals that lumbered along or swift warm-blooded creatures like those depicted in “Jurassic Park”?  (more…)

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Mammals Grew 1,000 Times Larger After the Demise of the Dinosaurs

*NSF enabled the assembly of an international, interdisciplinary team that was the first to quantitatively document body size patterns over the past 100 million years*

Researchers have demonstrated that the extinction of dinosaurs some 65 million years ago paved the way for mammals to get bigger, about a thousand times larger than they had been when dinosaurs roamed the earth. The study, released in the journal Science, is the first to quantitatively document the patterns of body size of mammals after the existence of dinosaurs.

About the Image: The largest land mammals that ever lived, Indricotherium and Deinotherium, would have towered over the living African Elephant. Indricotherium lived during the Eocene to the Oligocene Epoch (37 to 23 million years ago) and reached a mass of 15,000 kg, while Deinotherium was around from the late-Miocene until the early Pleistocene (8.5 to 2.7 million years ago) and weighed as much as 17,000 kg. Image credit: NSF RCN IMPPS (more…)

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