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In the news
The tiny fossils were found compressed between layers of shale taken from a road cutting near Grahamstown. The small, predatory creatures, which would have snacked on the world's first primitive insects and millipedes, were almost the length of a modern-day pencil. Dubbed Gondwanascorpio emsantsiensis by its discoverer Dr Robert Gess of Wits’s Evolutionary Studies Institute, details of the new species have been published in the latest volume of the scientific journal, African Invertebrates. Back in the Devonian, between 420 and 360 million years ago, the world consisted of two supercontinents: Laurasia, comprising North America, Europe and Asia; and the southerly Gondwana, including Africa, South America, Australia, Antarctica and India. The two were separated by a deep ocean. Gess said that although it was known that Laurasia was inhabited by diverse invertebrates before and during the Devonian, “until now, we had no evidence that the early plant life of Gondwana was similarly inhabited”. Among other fossils found by Gess in rocks from the Eastern Cape site are 20 types of fish and a range of different land plants. At the time these existed, the area was on the edge of a high latitude coastal lagoon. Source: SAPA
The principles of hydroponics and aquaculture are integrated to raise fish and plants together in separate units. The plants, which include anything from lettuce and water lilies to tomatoes, should get most of their nutrients from the water that circulates out of the fish ponds. This farming method is slowly picking up in South Africa, with an abalone farm in Hermanus, a shellfish farm in Saldanha and a trout farm in Franschhoek adopting it. On a smaller scale, a restaurant at the V&A Waterfront has an aquaponics system. According to the UN Food and Agriculture Organisation, aquaculture has grown rapidly over the past 30 years. In the 1970s aquaculture accounted for about six per cent of the fish available for human consumption. In 2006 it was 47 per cent. Source: Cape Argus
When it comes to the world’s fastest land animal, the fascination is always with speed, but ecology and energetics specialist Dr Michael Scantlebury, from Queen’s University Belfast, had a different question. “What are the energy costs of a hunt?” he asked. “How fast must a cheetah go? How much effort must they put in to catch their prey?” To calculate this, the team attached collars to the cheetahs. On each collar was a GPS, capable of measuring where a cheetah was at intervals of less than a second; this would measure the animal’s hunting track. But the collars also had accelerometers, measuring not only how fast a cheetah was accelerating, but its orientation - how it was twisting and turning its body during a chase, much like the sensors in some phones flip the screen when rotated. What they found was surprising. “We always believed that cheetahs see their prey, run fast, catch it and kill it,” said South African co-author Dr Gus Mills, from the Lewis Foundation, who physically observed the hunts. “What we were surprised by was that the cheetahs don’t run so fast,” said Mills. Instead, the hunt was broken down into two parts. First, the cheetah accelerated rapidly, narrowing the gap between its intended prey. Then it slowed down. It is impossible to turn quickly at high speeds, so as it gets closer to its prey, a cheetah trades speed for agility, mimicking the prey’s darting escape tactics. This slowing-down period is prey-specific: for more darting, agile animals like ostriches and hares, they slowed down more. For the larger prey that did not jink as much, such as gemsbok, they slowed down less. It explained why the speed measurements were lower than expected: the cheetahs were compromising their speed according to the behaviour of the prey. Just as the prey had evolved different escape strategies, so had the cheetah’s hunting tactics evolved. Source: The Star
The breakthrough has far-reaching commercial applications, as Upsalite (named after the University of Uppsala, where the Swedish team is based) is the world's most efficient water absorber, with potential to be used for the removal of moisture in drug creation and high-tech electronics to cleaning up huge oil spills. Other uses include ice hockey rinks, warehouses, the collection of toxic waste or chemical spills and odour control. A single gram of this elusive white, dry, powdered form of magnesium carbonate (MgCO3) has an extraordinarily large surface area of 800 square metres thanks to numerous minuscule pores, each one a million times smaller than the width of a human hair. MgCO3 is also about as dry as a material can get, a property which, combined with a huge relative surface area that is inundated with pocket pores, makes it the world's best mop. The only problem was that, until now, this absorbent form of magnesium carbonate could only be produced by a process that was so expensive and involved so much heat that it wasn't remotely feasible to use it. The findings have been published in the journal PLOS ONE. OTHER ACCIDENTAL DISCOVERIES Penicillin The colour mauve Coca-Cola Pacemaker Microwave Sources: British Science Association & The Independent |
