This looks like an interesting field of study, but some of the media coverage behind the image of a plucky (almost cuddly) little fish has rested on some strange pseudo-science.To study the mechanisms by which zebra fish can rebuild damaged heart muscle may well be valuable. (Newts have the same capacity, but are perhaps a little less sexy.) We may not want to address the question of how the damage is initially inflicted.
Most of the descriptions of the project seem to have been quite reasonable. In fact, most of them were just regurgitations of the same press release. However, at least one BBC report suggested this was a capability we humans had lost over the millennia (now what would the selective advantage of that be?) since - as we all know - we were all fish once. They don't seem to have realised that not all fish can do this so, unless most species in the world have also lost it in development, it wasn't a very sensible addition to the story.
By the way, experiments with rats (even less sexy) in 2008 showed that injecting a drug cocktail into a damaged heart could stimulate some regrowth. But this is a new campaign, and I wish it well while feeling some sympathy for the zebra fish who will be laying down their lives for us.
