This cannot be explained by the Standard Model of Physics (which relies entirely on gravity as the only formative force in the universe) and ignores electromagnetism even though EM is 39 orders of magnitude more powerful than gravity and even though magnetic fields ONLY arise as a consequence of electric currents.

Until astrophysics accounts for the electric currents that are necessary to produce the incredible magnetic fields found in space and that characterize stars, the state of the science will remain moribund.

Andromeda and the Milky Way will merge in about 4 billion years. So, send our fastest spacecraft, plant the seeds and let them grow.

Resisting Radiation – By Leslie Mullen – Mar 20, 2006

astrobio. net/topic/origins/extreme-life/resisting-radiation/

…the only organisms known to survive space exposure – at least in the short term – are bacteria and lichen. Bacteria need some shielding so they won’t get fried by the UV, but lichen have enough biomass to act as a protective spacesuit.

But even with a good barrier in place, sometimes radiation damage does occur. The lichen and bacteria hibernate while in space – they do not grow, reproduce, or engage in any of their normal living functions. Upon return to Earth, they exit this dormant state and, if there was damage inflicted, proteins in the cell work to piece together DNA strands that were broken apart by radiation.

So far as tunas and other marine animals are concerned, there can anyway never be such a thing as a “sustainable fishery,” correctly understood. The term belongs to an old-fashioned, proto-scientific way of thinking at best. In fact, ecosystems are far vaster and more complex than we can understand at all well; the interplay of organisms is too hard to comprehend; and then, the effects of global warming / climate change, including especially the increasing acidification of ocean waters, are an important and huge new set of factors. So for a number of reasons, the prudent thing is to give up expecting tunas ever again to be reducible to a menu item.