Now that I’ve learned all about this thing called a Joke, thanks Khangol, I have a different question about the aphids column.
When [m]ale and female aphids mate in autumn is the same… cell (egg?) in the mother fertilized as would, without the intervention of the male, parthenogenetically become a new (female) aphid?
Also, is there any way a female could parthenogenetically bear male offspring?
From Cecil’s column and the Wiki link in the OP, the parthenogenic offspring would seem to be genetically identical to the mother, so no males could result without a father’s participation. However, I’m not an expert on aphid genetics.
I found it odd that neither Cecil nor Wiki mentioned the role ants play in the aphid life cycle. In many aphid species, aphids are like cows to the ant colony. In the fall, ants take aphid eggs down into the underground ant nest. In the spring, the ants carry the hatchlings up to the tender new shoots of the plant. The aphids feed on plant juices, and they excrete a sweet, sticky poop. The ants come back and collect the sweet poop as food for the colony.
If you’ve parked under a tree, you probably have seen little spots of aphid poop (nope, it’s not sap) on your car. They start out clear, and then turn dark. You may have seen ants scampering up and down tree trunks, and now you know why.
MMMmmm, aphid feces!
Leads me to two conclusions.
Males do not fertilize the same cells that parthenogenetically lead to live offspring. (Not a well founded conclusion.)
And:
Females determine the sex of the offspring.
Cecil has written more on the subject of parthenogenesis.
Thanks for that Chronos. I saw Turkeys mentioned in the wiki article and wondered about how that could work. I assumed aphids would be a simpler place to start.
In Turkeys, I assume, the basic process is the same. Cecil even mentions the possibility of a male, um, interacting with a female and the female opting to disregard his input. So to speak.
That leads me to think that the female produces an egg and, let’s say there are no males around or they’re all just to pushy or immature or they’re watching football or they’re Republicans, then the female lays the same egg and, without benefit of intercourse, has a viable offspring.
The process in aphids appears different on the surface. It’s sounds to me as though the females have two reproductive strategies if not different systems. The sexual reproductive system and the parthenogenetic system.
I’ll have to do some more research on virgin birth and whether or not the resultant offspring in Turkeys are always female.
Well, let us know what you unearth, SiXSwordS. As I understand the turkey biz in the US, most of the adult turkeys sold are males, as they develop the massive muscles the market desires. I’m beginning to doubt my earlier conclusion about aphids and turkeys producing only females without mating with males.
I already said I was not an expert on aphid genetics, and now I’m looking ignorant about turkey breeding, too. This is not embarrassing. Learning starts with finding out what you don’t know. It’s tempting, but I won’t spring into Rumsfeldic philosophy. I always get dizzy when I do that. 
I think this is true with turkeys, but I’m not sure about aphids. As I quoted earlier, female aphids have two sex chromosomes and males only one. Obviously, the logic quoted above doesn’t apply. However, I think with aphids, the sex chromosome isn’t the point. Without fertilization, the female is reproducing asexually and, I’m guessing here, the offspring has to be identical to the parent.
I think you’re right about one thing. This thread is more a display of my ignorance than a learning tool. Maybe better to let it rest in peace instead of posting the results of my muddleheaded Googling.
Do turkeys use the same sex chromosone system that mammals do, though? I seem to recall somewhere that in birds, the females are heterozygotic, while the males are homozygotic, contrary to the mammalian system.
It’s been awhile but it was always my understanding that through parthenogenesis both aphids and turkeys give birth to female offspring. In the case of aphids they bear live offspring who’s offspring are already forming when they’re born. With turkeys the only way it can be done is a near lethal lab fertalization by cold shock or some sort of injection that causes the # of chromosomes to double, hence female offspring.
No, and not only is it different, but it is not entirely understood:
emphasis added
In some discussions of aphid reproduction it is noted that males appear in much greater numbers in the fall and also that it is winged females that start new colonies. (see wikipedia links.) Not that Jurassic Park is going to fly as a cite, but one can imaginie the benefit if a single female or a female only population could propagate a species. If any female (identical or otherwise) could potentially morph into a male, a single female would be able to engender an entire clan.
I was referring to the “natural” process, rather than the cloning process that might be used in a lab.
It isn’t a natural process with turkeys as it is with aphids, that’s what I’m saying.
Aphids and some bees are able to produce offspring parthenogenetically.
[quote]
If any female (identical or otherwise) could potentially morph into a male, a single female would be able to engender an entire clan
[quote]
Lots of fish are able to change sex.
http://www.straightdope.com/classics/a991008a.html
A cite would help. I’ll try a search in the mean time.
I don’t have a site, I took embryology in grad school and it’s been awhile.
Lots of fish do though, try looking up salmon. I’ll try to find a site for you.
Something about Sea Bass
I have to admit I’m amazed at how common this is. I found more links than I could even wade through. River Salmon, Reef fish, Sea Bass…
http://www.bio.davidson.edu/Courses/anphys/1999/Rice/Rice.htm
Many of the links I looked at mentioned that females become males when there is a dearth of males. In one, the comment was that when the dominant male disappeared, for whatever reason, the dominant female would become male.
Considering the cost of males, I have to wonder if aphids, at least, aren’t taking advantage “cloning” females while using sexual reproduction to maintain variable offspring.
As you say, sex determination in most aphids is an XX/XO system. Females have two X chromosomes, males have one X (and the single X lacks a partner).
All aphids start out XX, that is, female. Males are produced when one X chromosome is lost during development. A female can give birth to both males and females parthenogenetically.
Furthermore, a male aphid can father only females. Although he could in theory produce X and O sperm, in practice only X sperm are produced. Since both parents contribute an X, only females are produced by sexual reproduction.
That’s exactly what they are doing. Cloning is the best way to maximize your reproductive rate, but the disadvantage is that you lose genetic variability and the possibility of adapting to changing conditions. Aphids reproduce sexually after several parthenogentic generations in order to maintain genetic variability within their populations.
Thanks Colibri. I’ve been away from the computer or I would have said as much earlier.