posted on Jan, 15 2010 @ 08:48 PM
Quote from source:
Alligators have a one-way path for breathing that is similar to birds’, new research shows. The findings, published in the Jan. 15 Science, could
explain how dinosaurs’ ancestors rose to prominence.
“It’s absolutely transformational,” comments Adam Summers of the University of Washington’s Friday Harbor Laboratories. “It really makes us
think hard about our interpretations of anatomy.”
Unlike a mammal’s breath, which exits the lungs from the same dead-end chambers it enters, a bird’s breath takes a loopy one-way street through
In mammals, air enters the lungs and flows through a network of branching tubes called bronchi, which culminate in small cul-de-sac chambers where
blood vessels exchange carbon dioxide for oxygen. Air then exits the lungs via the same pathway
Interesting research, and good to see we are finally studying the most ancient animals on earth. Alligators are interesting and have lived on earth
for a long time so to see how their systems work will help in the our understanding of evolution and the dinosaurs.
The finding could mean that this mode of breathing is far older than scientists suspected and that it may have helped archosaurs, the common
forebearers of birds, alligators and dinosaurs, rise to a dominant ecological niche millions of years ago.
Archosaurs were the largest land animals on Earth from after the Permian-Triassic extinction 251 million years ago until the group split 246 million
years ago into alligators and what would become dinosaurs and birds. To rise to prominence, archosaurs had to unseat large mammal-like reptiles called
synapsids. But synapsids flourished after the dinosaurs went extinct, eventually leading to today’s large land mammals. How archosaurs gained their
brief time on top remains a mystery.