In this week’s Sunday Science stories…a step forward in the fight against rabies, ancient dogs, an artificial leaf, why legalising the ivory trade won’t save the elephants, and measuring the heartbeat of the biggest animal on the planet…
A breakthrough in the fight against rabies, a nasty disease transmitted largely by infected dog bites. The disease is almost always fatal: a vaccine exists, which can successfully treat people, but it has to be given very soon after exposure, and before symptoms appear. It’s also very expensive. The disease still kills around 60,000 people a year. Researchers have discovered how rabies produces a particular protein which shuts down immune responses in the host, and have been able to make amodified versions of the virus which doesn’t do this, in the hopes of making a far more effective vaccine – possibly that could be taken orally. Arguably, mass vaccination of dogs with the existing vaccine is something governments should be putting money into, but this offers a promising new alternative. Original study published in Cell Reports here (open access, but technical).
How can we save the elephant? Poaching for their valued ivory tusks has consistently eroded their numbers, despite efforts to save them: African elephant populations have declined by an estimated 95% over the last century, although the ivory ban has allowed some fairly well protected populations to recover. This has led some people to advocate for legalised ivory sales from strictly managed elephant herds: but a new study suggests that even under optimistic scenarios, there will be nowhere near enough to meet demand. The study has its critics, but it looks solid to me: there simply aren’t enough elephants to keep up with demand, given how many years it takes them to reach maturity and reproduce. If anything, I would predict that legalisation will increase demand as ivory becomes a more acceptable high-status product if it’s been “ethically” produced. The legalisation argument also relies on the supposition that legalisation will eliminate illegal poaching, which is hopelessly naive. Besides, should we really be killing a such a highly intelligent, social creature anyway, for something so trivial? Original paper published in Current Biology here (open access).
Scientists working at the University of Cambridge have developed an “artificial leaf” that uses carbon dioxide, water and the energy from sunlight to make syngas, a useful fuel. Importantly, unlike current syngas production, it doesn’t generate any extra carbon dioxide in the process. Artificial leaves have been made before, but generally they make hydrogen, so this is a nice step forward in solar fuels. Original paper published here in Nature Materials (paywalled)
For the first time, researchers have managed to measure the heartbeat of the largest animal on the planet, the blue whale. During deep dives, the heartbeat slows to as low as 2 beats per minute, but at the surface, when the whale is replenishing its oxygen supply, it rises to a surprising high of a 25-37 beats per minute. The heart appears to be working at the maximum limit of what is possible, suggesting an upper size limit on animals. There’s a nice news piece from the researchers here(with a very good infographic) and the original study is published in Proceedings of the National Academy of Sciences here (open access).
And finally, this week’s featured image is of “Dogor” (“friend”), an 18,000 year old puppy that was found remarkably well-preserved in the Siberian permafrost. Surprisingly, analysis so far is rather ambiguous as to whether it is a true wolf (which you would expect, at that age), or a proto-dog. Somewhat more recently in time, the Center for Paleogenetics in Sweden which has custody of Dogor has also published a study indicating that the sled dogs which helped the Inuit expand across the American Arctic 4,500 years ago had a unique genetic make-up. Original paper published in the Proceedings of the Royal Society for Biology B here (open access).