Author: BBC World Service

For their fans, jigsaw puzzles are a satisfying challenge, a focus, a chance to put everything else aside for a moment and be creative. But for other people they’re a frustrating jumble of random shapes and colours, a pointless task which is best left in the box. CrowdScience listener Heather is definitely a fan. She loves doing jigsaw puzzles and she wants to know why some people are so good at them. What skills do you need to find a pattern amongst all those shapes and colours? How do our brains, eyes and hands assemble the fragments into the finished article? And why do we enjoy doing them anyway? Presenter Alex Lathbridge puts together the pieces to answer Heather’s question. He sits down to work on a jigsaw with Sarah Mills, the ten-times UK jigsaw puzzling champion (yes... competitive jigsaw puzzling really is a thing!) As he watches Sarah complete the puzzle at lightning speed he gets a few of her top tips. So what’s going on in our brains when we’re doing a jigsaw puzzle? How do we recognise and process colour and shape? Prof Mark Mattson from Johns Hopkins University in the USA has the answer. And it’s all to do with a little seahorse-shaped part of the brain called the hippocampus.

Alex also explores the effect of jigsaws on our brains with neuropsychologist Dr Patrick Fissler. He’s carried out research to investigate the benefits of jigsaw puzzles on our brains as we grow older.

Both listener Heather and ten-times-champion Sarah seem to be better at jigsaws than Alex is. So, based on that sample size of three, women are superior puzzlers compared to men! But has anybody actually cast the net wider to see if that’s really the case? Alex talks to Daniela Aguilar from the University of Lethbridge in Canada about her study to investigate exactly that – and she reveals the results. Heather’s also wondering if any other species enjoy puzzles. And it seems they do! Alex meets Dr Cody McCoy from the University of Chicago to find out about the optimistic, tool-using crows of New Caledonia. From crows to competitive puzzlers, it seems we all relish a challenge!

Presenter: Alex Lathbridge Producer: Jeremy Grange Editor: Cathy Edwards Studio Manager: Bob Nettles Production Co-ordinator: Ishmael Soriano

This week we’re looking at a political agreement that will hand back sovereignty of the Chagos Islands to Mauritius. In the 1970s, the UK removed the entire Chagossian population to make way for a US military base. The islanders have been fighting for their right to return ever since. If deal can be agreed, the islanders are hoping they will have the chance to go home.

And this got us thinking about all things home-related.

First up, we discover the intriguing reasons why you can’t smell your own home, then we take a closer look at our homes and all the creatures that live there, before finding out about the ‘home scars’ created by limpets.

Next we hear from Dr Nadescha Zwerschke, a scientist who spent time on Rothera research station in Antarctica. She reveals how she made this isolated outpost feel like home.

Also, we reveal that global talks to agree a reduction in plastics have collapsed, which could have an impact on all our homes from a pollution perspective.

And finally – a type of pasta that would be no good for your homecooked recipes.

Presenter: Marnie Chesterton, with Tristan Ahtone and Godfred Boafo Producer: Alice Lipscombe-Southwell, with Harrison Lewis and William Hornbrook Sound engineer: Gavin Wong

Scientists have found that just one mutation in the current H5N1 virus in cattle can switch its preference from avian to human receptors. Jim Paulson and colleagues at the Scripps Institute did not use the whole virus to investigate this, but proteins from one of the Texas farm workers found to be infected. It suggests the bovine H5N1 virus has already evolved subtly. Meanwhile, Richard Webby of St. Jude Children's Research Hospital in Memphis helps us catch up on the latest known about the case of the Canadian teenager taken seriously ill a month ago with a different variant of avian H5N1. A debate has been rumbling this last year about the extent of ocean warming by, perhaps paradoxically, the reduction of particulate pollution from the fuel used by ships. The idea is that the small particles of sulphates and nitrates in the soot from funnels actually formed clouds over shipping lanes out at sea. This in turn sheltered the oceans to some extent from solar radiation, thus making latter decades of the 20th century seem cooler than they would have measured today. Hence, removing the particulate pollution from bunker fuel, mandated by the International Maritime Organisation a few years ago, may have contributed to the surge in ocean temperatures witnessed in the last two years. Daniele Visione, of Cornell, and colleagues have done the modelling and found that there has indeed been a noticeable effect. But earth’s oceans are certainly not as hot as Venus’ ones, if indeed such oceans ever existed. It has long been held that once upon a time our sunward neighbour might have possessed liquid water oceans, long since boiled off by runaway greenhouse effects of the atmosphere. But, breaking with science fiction visions of aliens paddling in temperate seas, Tereza Constantinou of Cambridge University has been looking at the gases coming out of the volcanos on Venus, and has concluded that the planet never had such surface water, basically because the rocks from which magma is made don’t billow steam when they boil today. Presented by Roland Pease Produced by Alex Mansfield with Debbie Kilbride Production Coordinator: Jana Bennett-Holesworth

(Image: Bird Flu in Dairy Cows; Credit: The Washington Post via Getty Images)