Kin Selection & Altruism

Nice post. Absolutely. The other important issue is that when dealing with transfer and especially plasmids, the donor is not losing genetic resources. A cell may contain a hundred copies of the same plasmid - giving a few away is a small expenditure of resources, and whatever genetic benefit the plasmid may be conferring is kept by the donor.BUT, an important point that I think both you and RAZD have overlooked: A donor cell definitely gets a strong benefit in transferring antibiotic resistance to its friends and neighbors.There are various ways of becoming resistant to antibiotics - but one of the most commonly transferred ways involves passing on genetic info for the production of enzymes that break down the antibiotic.A cell with this mode of resistance produces these enzymes, hopefully (for the cell) in sufficient numbers to reduce the antibiotics to survivable levels in its local area. If said cell is surrounded by other cells all breaking down the antibiotic, then the active antibiotic levels will more likely be brought down to survivable levels for everyone involved.If sufficient numbers of cells are involved, the amount of energy expended producing resistance enzymes drops for all the cells involved, and can eventually go to zero if all the antibiotic is broken down.So is there a benefit to transfer of antibiotic resistance?Increased chance of survival. Reduced energy expenditure. Hell yeah.

Quite right, but the existence of plasmids whose transfer to other cells directly benefits the donor means that a mechanism of such transfer could have readily evolved, and thus we have no need to invoke altruism. Plasmids aren't genomic.But evolution is often a case of balancing competing interests. If you see that as a "battleground", so be it. I prefer to see it as exquisite, life-permitting compromise.

Obviously you didn't actually read my explanation of how donor cells benefit from transfer of antibiotic resistance to their neighbors.The specific, individual donor cell is more likely to survive and reproduce, and reduces its own energy expenditure, if it transfers info on how to break down antibiotics to its neighbors.This is the exact opposite of "benefit the species as a whole".

Not really. Why philosophical?Terminology is in place for a reason - extragenomic DNA like plasmids and mitochondrial DNA behaves very differently than the genome itself. I lost my penis because I don't think the genome is at "war" with itself!?!!?! ARGhgHHH!?!? My penis!!![edited: because I forgot who I was responding to for a minute...]This message has been edited by pink sasquatch, 12-10-2005 10:08 AM

I don't think we need to invoke philosophy regarding these technical terms. Mitochondrial genomes behave much differently than the genome proper, so a distinction is made in the terminology. Similarly, plasmids in a bacterium behave much differently than the bacterial genome, so a technical distinction is made. If part of the DNA of a plasmid or mitochondrion integrates into the genome, it becomes genomic DNA.It's really much more mechanical, not really philosophical. You're not the first to try to determine if sasquatch coat color is sex-linked...

I never did so.I simply stated that this is a nice (common) example of how gene transfer directly benefits the donor.Thus, there is no need to invoke altruism or species-level selection to explain the evolution of such gene tranfer.I'm not saying that this is the scenario in which gene transfer evolved, I'm simply saying similar conditions could have led to selection for gene transfer attributes.No altruism needed.

What other cases? I'm talking about hypothetical non-altruistic possibilities for the arisal of gene transfer during evolution.[Quite frankly, RAZD, most of your posts over the past few days have left me thinking, "what the fuck is he talking about?"]

I was clearly discussing the evolution of gene transfer, something you had identified as altruistic behavior, claiming that there was no benefit to the donor cell.I showed that you were wrong in many cases.I never said all cases, despite the fact that you've tried to insist that's what I meant multiple times (no wonder you're having communication problems arguing against assumptions...)I don't think "never" is necessary to negate a process as being altruistic. By your logic it seems that, say, cichlids producing young are being altruistic by providing food to predators, since it is rare that every single one of their young survives past fry stage. Altruism does not need to be invoked just because a behavior that benefits other organisms does not give a 100% return on the "donor" organism's investment - most behaviors are inefficient, including those that benefit others - a net benefit to the donor is all that is needed to negate altruism.In the case of your single cell, perhaps it seems to you in your simplistic model that its "donation" of a plasmid to another cell is a sign of altruism. It is ignoring the reality that the donor cell under normal circumstances is likely to get something in return - either novel genetic information during transfer, or a neighbor who is going to help make something it needs to survive.The occasion that the donor cell doesn't get a return on transfer isn't altruism by any means - instead, it is the donor getting screwed on its investment. You decided to entirely ignore context, point out flaws in logic that don't exist, argue against assumptions, and point out strawman arguments I haven't made.Isn't it funny that your communication skills are fine until someone solidly counters one of your assertions? Then suddenly you-no-speaky-the-english, and you meant something else entirely.I'm tired of this shit.

Hey Cal,I don't think I really disagree with anything in your post.But to continue with your idea of "behaviors" and "interests" - I think we need to also keep in mind that many of these "behaviors" are "gambles", in that they don't always benefit a given entity's "interests".Just because these "gambles" occasionally pay-off for the "interests" of others, but not of the "gambler", does not mean that the "gambler" was acting altruistically.I think this is where RAZD's supposed altruistic gene transfer fails - it assumes "philanthropist" where it should be assuming "gambler".Sorry about the anthropomorphism... (Though I enjoy the metaphor...)

Thanks for deciding again to whine about what you see as errors in the logic of my post rather than discussing the content. Actually, I was discussing the evolution of gene transfer "altruism" with Cal and you engaged me. Therefore, the discussion was about gene transfer in an evolutionary perspective before you entered it.Therefore it is you who is guilty of "arguing a position that is 90 degrees to the discussion in spite of repeated attempts otherwise."And you wonder why I get pissed off...Ridiculous. You don't own the thread and get to decide what is and is not discussed.enjoy.

Well put. I think true understanding of the power of steady, subtle, sustained bias is something that is a difficult concept for many who reject evolution on a "common sense" or "personal observation" basis.(Again, I agree with the content of your post, and am trying to decide how I feel about evolution-as-casino metaphors...)

You are conflating "your discussion with Cal" with "all discussions with Cal."That is a logical error.enjoy.

Okay, but "losing" organisms aren't always "removed from the game" based on an individual gamble, so your statement is an exaggeration.The quote you were responding to... ...contains two different ideas. The first sentence addresses "gambling" at an individual level; the second, by bringing in reproductive success, implies "gambling" at a species level.All behaviors are inefficient, and thus may be a gamble for an individual. When that individual is interacting with other organisms, the gamble the individual makes may pay off for another organism, but not the gambler.This does not mean that "altruism" has occurred. It is about odds and "expectations".This brings in Cal's idea of the casino - casinos do very well by maintaining a slight edge, which means they lose many hands. To say that the casino is being "altruistic" whenever a player wins a hand is absurd, since the casino is playing the odds and always gets a net positive return on its investment.If an individual cell gets a return on its gene transfer investment 90% of the time, the 10% of the times that it doesn't get a return aren't "altruism", they are failed gambles.