April
2007
News from the isotopes0
23-Apr-2007 One of the weirdest organisms that ever lived, Prototaxites had tree-like trunks that stood more than 20 feet high, making it the largest known land organism of its time – 420 to 350 million years ago. It has been classed as a conifer, a lichen and various types of algae. But carbon isotope analysis of the fossil and the plants that lived in the same environment has shown that Prototaxites “displayed a much wider variation in its ratio of carbon-12 to carbon-13 content than would be expected in any plant.”
This supports the idea that the beast was actually a “humongous fungus“, says Carol Hotton of the National Museum of Natural History.
This is an application of the same technology, derived from the difference between C3 and C4 photosynthesis, as the previous story
9-Jan-2007 Paranthropus is an ancestor of modern humans who has often been seen a a specialist who lacked a varied diet. That is why Paranthropus went extinct, it was thought, as the climate changed and Africa became drier, while tool-wielding Homo, with a highly varied diet, survived. But a new study, using carbon isotope analysis of four fossil teeth, shows that Paranthropus also ate a variety of foods and the explanation for extinction must go deeper. Story and science teaching resources (US or UK English) posted at www.realscience.org.uk
