Largest/Most Complex Life Form Using Asexual Reproduction?

Factual Questions
21

[QUOTE=Colibri]
There’s quite a few lizards and some salamanders as well. These are mainly triploid, the lineage originally having been produced by an interspecific cross. Because the triploidy screws up meiosis, asexual reproduction is the only option they have.
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I stand corrected, or rather, extended and superseded…but only with pride by the best of company.

Stranger

22

[QUOTE=sjc]
It seems to me “parthenogenesis” by definition assumes the species reproduces sexually (or ought to be capable of sexual reproduction); the term “virgin birth” is pretty much meaningless if the possibility of sex is nonexistent.
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Not necessarily; if the species is diploid (or as mentioned by *Colibri, multiploid) but incapable of sexual reproduction with other members of the species (through incompatibility, atrophy of reproductive organs, et cetera) it may be only capable of parthenogenic reproduction, i.e. “virgin birth”.

Sunday morning tales aside, however, parthenogenic reproduction has never been observed in mammals, and there are good reasons to believe that it wouldn’t be viable for it to develop, at least not naturally along the lines of extant parthogens.

Stranger

23

Since dinosaurs were distant ancestors of avians by most assessments (or reptilian perhaps by some) they were probably capable of parthenogenesis. Hard to get much bigger than a self fertilizing Seismosaurus.

24

[QUOTE=Stranger On A Train]
I stand corrected, or rather, extended and superseded…but only with pride by the best of company.

Stranger
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Your post was pretty good for a rocket scientist. :wink:

25

This seems an apt time to mention that certain flatworms are hermaphroditic as well, and decide who gets to impregnate whom via a contest of penis fencing. Whichever one manages to penetrate the other first, wins.

26

[QUOTE=Sampiro]
Since dinosaurs were distant ancestors of avians by most assessments (or reptilian perhaps by some) they were probably capable of parthenogenesis. Hard to get much bigger than a self fertilizing Seismosaurus.
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Read post #9.

27

[QUOTE=Spectre of Pithecanthropus]
Birds, really?

Does this mean that every so often a chicken will lay some fertile eggs even if the rooster hasn’t been around in weeks? When does parthenogenesis in birds occur, and is it limited to certain species or families?
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I know of it in finches and turkeys and chickens off the top of my head, but perhaps other, more knowledgeable posters will elaborate on that.