The idea that we might be robots is no longer the stuff of science fiction; decades of research in evolutionary biology and cognitive science have led many esteemed scientists to the conclusion that… humans are merely the hosts for two replicators (genes and memes) that have no interest in us except as conduits for replication...
It seems to be stretching the definition of “host” in biology quite a bit to say that an organism is “host” to its own genes. It seems rather like saying an organism is in a symbiosis with itself. Organisms are host to their memes, and to the genes of their gut bacteria—but their own genes are more like a part of them.
Organisms are host to their memes, and to the genes of their gut bacteria
Unless the gut bacteria where somehow only transmitted from say mother to children. Then it is basically like mitochondria, a integrated part of that particular organism.
But where does this leave “driving genes”—alleles that help themselves rather than the bearer. It is quite easy to imagine such a gene. To take the metaphor of a computer program:
Gene X: When sexual recombination occurs ALWAYS copy this line.
Clearly this dosen’t add to the usability of the program or the fitness of the organism one bit. Another line of our allegorical computer program:
Gene Y:When reading Gene X substitute "this line" with "lines A to Y".
So the line between a driving gene and a “regular” gene depends on its envrionment, that includes other genes. I know from your writing that you are familiar with gene-centered view of evolution.
So in sexually reproducing animals it seems that host may indeed be an appropriate word for the relationship between the organism and its own genes. After all to consider regular usage the mitochondria—rest of cell relationship is often considered a symbiosis. It really comes down to how useful it is to break down host-parasite/smybiont-smybiont systems versus just calling them “organisms” for convenience.
Organisms are host to their memes, and to the genes of their gut bacteria
Unless the gut bacteria where somehow only transmitted from say mother to children.
That is certainly not how most human gut bacteria work!
But where does this leave “driving genes”—alleles that help themselves rather than the bearer.
Yes, some animal genes can act like parasites. Most animal genes are not like that, though!
After all to consider regular usage the mitochondria—rest of cell relationship is often considered a symbiosis.
Yes, that is still reasonable—mitochondria have different genetic interests to the host cells—e.g. they want to kill males. If that was the context, the term “symbiosis” would be fine.
“Host” terminology is still quite stretch, IMO. Symbiosis takes place when different types of creature live together. Cloned somatic cells are better regarded as being part of the same organism. The genes are not really in a symbiotic relationship with the “host”—there is only one creature involved here.
It seems to be stretching the definition of “host” in biology quite a bit to say that an organism is “host” to its own genes. It seems rather like saying an organism is in a symbiosis with itself. Organisms are host to their memes, and to the genes of their gut bacteria—but their own genes are more like a part of them.
Unless the gut bacteria where somehow only transmitted from say mother to children. Then it is basically like mitochondria, a integrated part of that particular organism.
But where does this leave “driving genes”—alleles that help themselves rather than the bearer. It is quite easy to imagine such a gene. To take the metaphor of a computer program:
Clearly this dosen’t add to the usability of the program or the fitness of the organism one bit. Another line of our allegorical computer program:
So the line between a driving gene and a “regular” gene depends on its envrionment, that includes other genes. I know from your writing that you are familiar with gene-centered view of evolution.
So in sexually reproducing animals it seems that host may indeed be an appropriate word for the relationship between the organism and its own genes. After all to consider regular usage the mitochondria—rest of cell relationship is often considered a symbiosis. It really comes down to how useful it is to break down host-parasite/smybiont-smybiont systems versus just calling them “organisms” for convenience.
That is certainly not how most human gut bacteria work!
Yes, some animal genes can act like parasites. Most animal genes are not like that, though!
Yes, that is still reasonable—mitochondria have different genetic interests to the host cells—e.g. they want to kill males. If that was the context, the term “symbiosis” would be fine.
“Host” terminology is still quite stretch, IMO. Symbiosis takes place when different types of creature live together. Cloned somatic cells are better regarded as being part of the same organism. The genes are not really in a symbiotic relationship with the “host”—there is only one creature involved here.