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Problematic urn-shaped fossils from a Paleoproterozoic (2.2 Ga) paleosol in South Africa Authors: 1. Gregory J. Retallack (a)2. Evelyn S. Krull (b)3. Glenn D. Thackray (c)4. Dula Parkinson (d)Affiliations:a. Department of Geological Sciences, University of Oregon, Eugene, Oregonb. C.S.I.R.O. Land and Water, Waite Campus, Glen Osmond, South Australia 5064c. Department of Geosciences, Idaho State University, Pocatello, Idaho 83209d. Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720Abstract:Small (0.3-1.8 mm long), locally abundant, urn-shaped fossils within surface horizons of a paleosol in the 2.2 Ga Hekpoort Formation near Waterval Onder, South Africa, are here described and named Diskagma buttonii Retallack gen. et sp. nov. The fossils are from fresh rock of a deep highway cutting, and have been metamorphosed to upper greenschist facies like their matrix. Despite metamorphic alteration, total organic carbon of the samples was 0.04% and its isotopic composition (?13C) was–25.6 ± 0.08 ‰ (two standard deviations) versus Vienna Pee Dee belemnite standard. Organic outlines of the fossils are also accentuated by recystallized berthierine and opaque oxides. The fossils are locally clumped within surface swales of a Vertisol paleosol, identified from characteristic penecontemporaneous deformation (clastic dikes between swales of mukkara structure) and from pronounced geochemical differentiation (phosphorus and copper strain-corrected mass-depletion characteristic of an oxidized biologically active soil). This paleosol's chemical composition is evidence of temperate humid climate (mean annual temperature 11.3 ± 4.4 °C, and mean annual precipitation 1489 ± 182 mm). Associated paleosols indicate atmospheric CO2 of 6640 +12880/-4293 ppm (0.6%) and 0.9-5% atmospheric O2. The best preserved examples of Diskagma are shaped like an urn with a flared rim, and closed below the flare. Observation of hundreds of specimens in thin section reveals substantial variation in growth (elongation) and decay (shredding and deflation). They had a hollow ellipsoidal interior that is unusually devoid of opaque debris, unlike the matrix. Diskagma is superficially comparable with lichens such as Cladonia (Ascomycota) and Geosiphon (Glomeromycota). Definitive reproductive structures remain unknown. They predate the oldest other likely fossil eukaryotes (1.9 Ga) and fungi (1.5 Ga), and current molecular clock estimates for eukaryotes (1.6 Ga) and fungi (1.1 Ga). Lichenized actinobacteria are plausible prokaryotic alternatives permitted by molecular clocks. Although biological affinities of Diskagma are uncertain, these fossils reveal the general appearance of Paleoproterozoic life on land.

China Readying 1st Moon Rover for Launch This Year #space

ANCHORAGE, Alaska (AP) — A heat wave hitting Alaska may not rival the blazing heat of Phoenix or Las Vegas, but to residents of the 49th state, the days of hot weather feel like a stifling oven — or a tropical paradise.

The U.S. spends more than $7 billion a year preparing classroom teachers, but teachers are not coming out of the nation's colleges of education ready, according to a by U.S.News & World Report and the National Council on Teacher Quality. The study says most schools of education are in disarray.

States that are implementing the Common Core academic standards and new standardized tests in public schools can have an additional year before they have to use those student test scores to decide pay and job security for teachers, Education Secretary Arne Duncan said Tuesday. The U.S. Education Department will decide on a case-by-case basis whether to grant the extensions for using new tests as a factor in personnel decisions, Duncan said. Some states already link the tests to teacher evaluations, while others had committed to using test scores in personnel decisions during the next two years.

Parents looking for ways to keep their children's minds sharp this summer can access libraries, museums, and even sample questions and activities, compliments of the "Nation's Report Card" -- more officially called the National Assessment of Educational Progress, or NAEP. In fact, NAEP is the largest nationally representative and continuing assessment of what America's students know and can do in various subject areas.

Water -- whether in raindrops or puddles, swimming pools or oceans, water tables or bathtubs -- tends to bring out strong feelings in children. For Heather, the primary emotion is fear. Followed by intense dislike: "She didn't mean to do it. She didn't enjoy it. But she fell in the water nearly every day, especially when she was wearing her good clothes." With a mix of realism, sensitivity and slapstick humor (lots of slips and splashes), MacLeod and Smith plunge poor Heather into one wet situation after another. Eventually, of course, there are swim lessons, and Heather and the water reconcile. All goes swimmingly in the end.

RT @NASASocial: We're extending the #ISS #NASASocial @NASA_Johnson registration until Noon ET Friday. More info at:

Our internal circadian clock regulates daily life processes and is synchronized by external cues, the so-called Zeitgebers. The main cue is the light-dark cycle, whose strength is largely reduced in extreme habitats such as in the Arctic during the polar summer. Using a radiotelemetry system a team of researchers from the Max Planck Institute for Ornithology have now found, in four bird species in Alaska, different daily activity patterns ranging from strictly rhythmic to completely arrhythmic. These differences are attributed to the species' mating systems and behaviours. The study shows that activity patterns can change according to social and environmental factors, which suggests a remarkable plasticity in the avian circadian system.

As data dragnets and information breaches dominate the news, states are scrambling to cash in on a rapidly expanding business sector by offering tax incentives to firms that protect sensitive information from outside attacks.