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The Mystery of Lizard Breath

By Guest PostDecember 19, 2013Nature3d image, aerodynamic valves, african savannah, alligators, archosaurs, c g farmer, ct scans, dinosaurs, emma schachner, evolution, fast metabolisms, flying pterosaurs, gular pumping, harvard university, humans, james butler, lepidosauromorpha, lizard breath, lizard like creature, lungs, mass extinction, monitor lizards, mystery, one way patterns, oxygen consumption, permian triassic, rate, robert cieri, tidal breathing pattern, tuataras, unidirectional airflow, university of utah, varanus exanthematicus

One-Way Air Flow May Be 270 Million Years Old

Air flows mostly in a one-way loop through the lungs of monitor lizards – a breathing method shared by birds, alligators and presumably dinosaurs, according to a new University of Utah study.

The findings – published online Wednesday, Dec. 11 in the journal Nature – raise the possibility this breathing pattern originated 270 million years ago, about 20 million years earlier than previously believed and 100 million years before the first birds. Why remains a mystery. (more…)

Why Bad Immunity Genes Survive

By Guest PostFebruary 10, 2012Health, Scienceankylosing spondylitis, antagonistic co evolution, antibiotics, arms race, autoimmune diseases, bacteria, cells, cornelius whitney hyzer, gene, genetics, george gilchrist, germs, immune system, infection, infectious diseases, james ruff, jason kubinak, major histocompatibility complex, mhc, mhc variants, mhcs, mice, national science foundation, parasite, pathogens, patricia slev, people, protein, university of utah, variant, vertebrate animals, virus, wayne potts

*Study implicates “arms race” between genes and germs*

Biologists have found new evidence of why mice, people and other vertebrate animals carry thousands of varieties of genes to make immune-system proteins named MHCs–even though some of those genes make vertebrate animals susceptible to infections and to autoimmune diseases.

“Major histocompatibility complex” (MHC) proteins are found on the surfaces of most cells in vertebrate animals. They distinguish proteins like themselves from foreign proteins, and trigger an immune response against these foreign invaders. (more…)

Six Million Years of African Savanna

By Guest PostAugust 6, 2011Environment, Scienceancient soil, anthony macharia, ape, ardipithecus, australopithecus, bipedalism, c3 pathway of photosynthesis, c4 photosynthesis, carbon isotope ratios in fossil soils, chemical isotopes, david kimutai korir, early human fossils, east african, environments, fossils of human ancestors, geochemist, geological past, homo, human ancestors, kenya wildlife service, michael bird, national science foundation, omo turkana basin of ethiopia and kenya, open grasslands, paleo shade proxy for soil temperature and woody cover, paleosols, paranthropus, prehistoric tree cover, ratio of rare carbon 13 to common carbon 12, richard lane, samuel andanje, savanna, savanna landscape, scattered trees, thure cerling, tropical landscapes, university of utah, vegetation chronologies of the awash valley of ethiopia, woody cover and hominin environments in the past 6 million years

*Open, grassy environments accompanied human evolution*

Scientists using chemical isotopes in ancient soil to measure prehistoric tree cover–in effect, shade–have found that grassy, tree-dotted savannas prevailed at most East African sites where human ancestors and their ape relatives evolved during the past six million years.

“We’ve been able to quantify how much shade was available in the geological past,” says University of Utah geochemist Thure Cerling, lead author of a paper titled “Woody cover and hominin environments in the past 6 million years” on the results in this week’s issue of the journal Nature. (more…)

Tag Archives: university of utah

The Mystery of Lizard Breath

Why Bad Immunity Genes Survive

Six Million Years of African Savanna