Everyone knows about how bacteria evolve to develop resistances to anti-biotics: most die but those with mutations that help them against the threat survive and produce more offspring, eventually leading to an entire population that is resistant to medicine. But what if that's not the whole story? What if bacteria without the mutation can be aided by bacteria with the mutation, leading to a resistant population much faster than would otherwise occur solely through genetic mutations?
Imagine that a cell that developed resistance can help its non-resistant neighbours by, say, secreting some substance that assists those neighbours in fighting off an antibiotic. This type of behaviour might make it easier for the whole bacterial population to avoid extinction. From the point of view of the bacterial species as a whole, it would avoid the need to wait for the rare resistant mutant to come to dominate the population. It would also ensure that population-level genetic diversity is maintained.
Lee et al. describe just such a charitable deed carried out by individual bacteria in a population of Escherichia coli subjected to an antibiotic. The authors show that mutations that develop in a few cells enable them to assist neighbouring cells that have not undergone resistance-conferring mutations. The actions of these few cells lead to a population-wide resistance. But they do so in a roundabout way that illustrates how antibiotic resistance can emerge from seemingly harmless and unrelated processes.
Source: Nature, September 2, 2010
Technically this isn't quite "altruism" on the part of the bacteria because the bacteria aren't making any conscious decisions to help out other bacteria. It is, however, still an example of one member of a group helping out other members of the group instead of simply struggling to survive on its own. It is from this sort of behavior that altruism would likely evolve -- it may not be altruism per se, but it is group cooperation and behavior designed to preserve the group.
It's common for conservative Christians to insist that without their religion, there'd be no reason for a person to ever help others instead of just helping themselves. Here, though, we may have an example of bacteria helping each other instead of just looking out for themselves. If bacteria can do it without gods or religion... or even a brain, it shouldn't be surprising to find humans doing it without gods or religion.
On the contrary, it should be a surprise if humans were the only creatures on the planet to need gods and religion to do what comes naturally to most: help each other. Why is it that only religious believers have trouble with the concept? Or is it that they are the only creatures on the entire planet that really do need gods and religion to accomplish what the rest of us do already? If so, that doesn't say much for them does it?
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