Monday, October 12, 2015

Rapid Adaptation

Human pressures have left no ecosystem untouched.  Catastrophists look at the trends and assume they will continue unchecked.  Of course nothing continues unchecked, except maybe black holes and even they are influenced by one another.

One scientists (momentary) inability to repeat his own experiment in coral bleaching serves as an example,

Rosenberg had come to a different conclusion. He’d noticed clumps of rod-shaped bacteria amassed at the borders of bleached regions of corals, suggesting infection. If he first treated the seawater with antibiotics, killing the resident bacteria, and then raised the temperature on corals in tanks, the corals never bleached. Heat alone didn’t drive disease, it seemed. Bacteria somehow contributed. 
He isolated one bacterium called Vibrio shiloi—a distant relative of cholera—that prompted coral disease. It was an opportunist: harmless at normal temperatures, but pathogenic when conditions grew warmer.In 1996, he published his findings in Nature. But now, a decade later, he and his graduate students tried to replicate the experiment, and failed—twice. The vibrio bacterium no longer seemed to cause disease.“The coral had become resistant,” Rosenberg told me. “This was a blow.” 
He began brainstorming possible explanations. Humans and other vertebrates have adaptive immune systems. With exposure to pathogens, our immune systems can learn and remember. When we encounter a pathogen we’ve seen before, we can repel it before it harms us. That’s the principle underlying vaccines. But corals lack an adaptive immune system. They couldn’t gain immunity from prior exposure the same way.

It turns out that just as a disease can move through a population like wildfire, so can a probiotic answer to that infection.  Moreover,the same human cargo ships that transport infections across vast oceans can't also transport probiotic responses to that infection.

Yep, invasive species can be your friend.

Creatures can adapt to changes in their environment not only through the multi-generational result of selection according to our genetic fitness to the environment but in the relatively short amount of time our symbiotic microbes.
Extinction and Evolution
Some researchers make a strong argument that the American microbiom has changed since the 1980's and is one of the forces driving the current obesity epidemic.  Right now it must remain at the level of hypothesis, you could fill hard drives with what we do not know about the microbes living within our digestive tracts.  I can only hope some future oriented surgeon at a research hospital is storing samples for future analysis of change over time.

Life is adaptive.  Yes, mass extinction is a pragmatic concern to those of us who want to see our species succeed over time, but extinction is not the only story at work.  Evolution is the yang to its yin.  From every mass extinction comes a new diversity.  Concern over the loss of the most present equilibrium is, at worst, a pragmatic concern, the equilibrium of the most recent past was good to our species.

Even our attempts to "think globally" are anthropocentric to the core.

But the earth doesn't care if our species succeeds over time.  The universe doesn't care and, ultimately, extinction is unavoidable.  By all means, examine your life and live a life of virtue, but virtue is a good part temperance.  In this case that means not thinking too highly of either yourself or our species.  Even if we make the planet inhabitable for homo sapiens, it has been before and it will be again.

You, the species, even the existence of any form of life on this globe is "only for now."

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