https://www.theguardian.com/lifeandstyle/shortcuts/2018/dec/11/one-set-twins-two-fathers-how-common-is-superfecundation
One set of twins – two fathers: how common is superfecundation?
Heteropaternal superfecundation will be tackled in a new romcom – but it happens in real life, too. Two experts explain how

Kasraie has found two studies of the incidence of heteropaternal superfecundation, both from the early 1990s. One author claims that one in 400 pairs of fraternal twins (those arising from two eggs) fits the description. The second author puts the figure at one in 13,000 cases of paternity. These sound like best guesses. “They do,” Kasraie agrees. He points out that we cannot know the true number, and research has been scant. Most cases come to light only when paternity is questioned and a DNA test carried out. Apologies if this turns out to be a spoiler.

dv said:

https://www.theguardian.com/lifeandstyle/shortcuts/2018/dec/11/one-set-twins-two-fathers-how-common-is-superfecundation
One set of twins – two fathers: how common is superfecundation?
Heteropaternal superfecundation will be tackled in a new romcom – but it happens in real life, too. Two experts explain how

Kasraie has found two studies of the incidence of heteropaternal superfecundation, both from the early 1990s. One author claims that one in 400 pairs of fraternal twins (those arising from two eggs) fits the description. The second author puts the figure at one in 13,000 cases of paternity. These sound like best guesses. “They do,” Kasraie agrees. He points out that we cannot know the true number, and research has been scant. Most cases come to light only when paternity is questioned and a DNA test carried out. Apologies if this turns out to be a spoiler.

…which the Gruin illustrated with a picture of identical twins.

> we cannot know the true number

We sort of can, statistically. Using blood groups. Blood groups are easy to find and are well known. Only a small percentage of multi-father twins will be identifiable using blood groups, but from those that do, we can extrapolate back to the true fraction of multi-father twins.

I think. I haven’t worked out the details.

“Human Blood: ABO Blood Types
https://www2.palomar.edu › abo_system
CAUTION: the inheritance of ABO blood types does not always follow such straightforward rules of inheritance”

Yeah? Perhaps they do.

mollwollfumble said:

“Human Blood: ABO Blood Types
https://www2.palomar.edu › abo_system
CAUTION: the inheritance of ABO blood types does not always follow such straightforward rules of inheritance”

Yeah? Perhaps they do.

I think more the question is, why wouldn’t they?

Common in some animal species. Sometimes very common.

mollwollfumble said:

Common in some animal species. Sometimes very common.

The sluts of the animal kingdom.

Witty Rejoinder said:

mollwollfumble said:

Common in some animal species. Sometimes very common.

The sluts of the animal kingdom.

you do have some issues that do need attention.

roughbarked said:

Witty Rejoinder said:

mollwollfumble said:

Common in some animal species. Sometimes very common.

The sluts of the animal kingdom.

you do have some issues that do need attention.

Wot me? Never!

Witty Rejoinder said:

roughbarked said:

Witty Rejoinder said:

The sluts of the animal kingdom.

you do have some issues that do need attention.

Wot me? Never!

hale and hearty are ye?