Not a lot, actually. I’ve been distinctly unimpressed with the offerings of new science bits on the interwebs lately. However, I have found some things that have piqued my interest. Some highlights for this week have included:
- deep-sea floor microbes are really, really old; and
- naked mole rats live for years (and are completely awesome, but we already knew that).
From work newly published in Science, we have some interesting insight into just how long microbes can live for. Researchers took sediment cores from the mud under the seabed in the Pacific Ocean, and measured the amount of available oxygen in each of the mud strata. Because they could plot the amount of oxygen that diffused through the mud strata, they could determine how much of it had been used by respiring microorganisms (ie, the amount of oxygen that was absent from the available amount). It turned out that samples had oxygen available 28 metres below the seabed, because the microbe communities were too sparse to consume all the available oxygen. It’s been 86 million years since those microbes were actually on the seabed itself. There have been many, many layers of mud deposited on top of them, yet they’re still there. Slowly consuming oxygen. Cool.
Naked mole rats!
I like naked mole rats. Apart from their really bizarre looks and ecology, they are also very useful models for human medicine as they have some amazing biological properties (they don’t seem to get cancer, for a start). One new aspect is their ability to get old, which for small rodents, is not usually an option. Many rodents have short lifespans, and for an animal of their size, the mole rats should not really live for very long – maybe 3-5 years. But they tend to live for about 30 years. And, instead of getting increasingly decrepit as they age, they stay healthy and sprightly.
We now have a better understanding of how they do that, thanks for research published in the journal Aging Cell. Researchers have found that naked mole rats don’t seem to have the same levels of decline in a growth factor called NRG-1 as observed in mice and humans as they age. What this means is that the brains of the naked mole rats seem to benefit from the ongoing protective aspects of having appropriate amounts of the brain growth factor – suggesting that it might not be increasing oxidation or other detrimental effects that cause reduction in brain function and lifespan, but rather the decline of the protective factors that allow it to happen. Either way, this further reinforces my assertion that naked mole rats are awesome critters.