Science: Silk clams, construction carbon, Yangtze fishing ban

Science commentator Laurie Winkless looks at how Korean researchers have taken waste from an abundant species of clams to recreate the silk produced from another, endangered species of clam. A study out of Canada has found that construction produces the equivalent of 1 - 3 metric tons of carbon per person each year - and it needs to drop by 10 % to stay on top of emission reduction targets - so how can it be done? And a fishing ban on the Yangzte River appears to be working, with fish biomass increasing