Tangled Bank #76 at Balancing Life

This is the mangolicious edition of Tangled Bank. Oddly enough, today I was reading in Carl Zimmer’s evolution that mangoes probably evolved to be eaten by large herbivores that were wiped out by humans. In addition to mangoes, you can read about birds, carnivores, lizards, cortisol and aging, and much more.

Tags: science, evolution, Tangled Bank, science writing, medical writing, natural history, organisms, Balancing Life

Night-owls of the world, unite!

Coturnix at A Blog Around the Clock tells of a movement in Denmark to let people who are naturally late risers and late to bed adjust their schedules to suit.

Greta Christina defends the Blasphemy Challenge

Greta Christina defends the appropriateness of a Blasphemy Challenge in these times and the right of non-believers to stand up and say what they think about religion and what it has done to them.

Photosynthesis 3.7 billion years ago

Danish researchers say rocks from Isua Rock in Greenland show that life-forms were using photosynthesis about one billion years earlier than has previously been shown.

“The researchers discovered abundant quantities of the element uranium in the ancient sediments, which had most likely precipitated out of ocean water.

“In a ‘reducing’ environment where little or no photosynthesis is taking place, the elements uranium and thorium would move around together in the ocean as mineral particles.

“But the high abundance of uranium relative to thorium in Isua rocks suggested that uranium had been chemically separated from thorium.

“This happens under ‘oxidising’ conditions, where organisms are releasing oxygen into the environment.

“Rosing and Frei conclude that microbes much like present-day cyanobacteria were converting sunlight to chemical energy through oxygenic, or oxygen-producing, photosynthesis.

“Anoxygenic photosynthesis, a form of the reaction that does not produce oxygen as a by-product, is widely thought to have evolved before the oxygenic form.”

Plate tectonics 3.8 billion years ago

Discoveries in Greenland have pushed back our knowledge of plate tectonics by another 1.3 billion years. A little bit of the earth’s crust survived, wedged onto on Greenland, when the rest of it plunged under North America. A similar piece remains on Cyprus. The typical geologic traces of tectonic action remain in these remnants.

Speaking of plate tectonics, I saw this witty T-shirt at the BookCrossing North America conference:

“Stop Plate Tectonics!”