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Author Topic: finding out the sex of a fossil  (Read 3439 times)

paul.fr

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finding out the sex of a fossil
« on: 30/08/2007 22:18:13 »
How is the sex of a fossil determined?


 

another_someone

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finding out the sex of a fossil
« Reply #1 on: 31/08/2007 00:38:34 »
Is this not taking necrophilia a bit far?

If you are talking about a species for which we do not previously know the skeletal differences between the sexes, then I suspect it is a matter of luck of finding a specimen which either has an embryo or egg within, or in some other way shows its sex in a direct way.

Ofcourse, increasingly we may be able to use genetics (even if the genes are too corrupted to give us an entire sequence, we may be able to extract enough information to give information on the sex of the animal) - but this may be easier for mammals and birds than it would be for reptiles or fish, since reptiles, amphibians, and fish, are not always sex determined by their chromosomes.
« Last Edit: 31/08/2007 00:40:14 by another_someone »
 

paul.fr

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finding out the sex of a fossil
« Reply #2 on: 31/08/2007 00:54:48 »
You take what you can get!

determaning sex with skeletal evidence is almost straightforward, and in humans is generally done with the pelvic bone. My question is about species that we know of (although, unknown is also interesting), some have the same bone structure and length.

If the fossilised remains were not nice and neatly flat, but say laid on their side would it still be quite easy to tell?
 

another_someone

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finding out the sex of a fossil
« Reply #3 on: 31/08/2007 01:53:46 »
determaning sex with skeletal evidence is almost straightforward, and in humans is generally done with the pelvic bone. My question is about species that we know of (although, unknown is also interesting), some have the same bone structure and length.

If the fossilised remains were not nice and neatly flat, but say laid on their side would it still be quite easy to tell?

The pelvic bone is the simplest and most obvious, but I believe other bones also show differences.

Even with the pelvic bone, even if the pelvis itself is missing, the hip joint on the femur should be different, as it will be taking different loading (because of the difference in shape of the pelvis to which it transmits its load).  There are even differences in the shape of the jaw (not as definitive as the differences in the pelvis - but we are generally still able to differentiate the silhouette of a female face from the silhouette of a male face with a fairly high success rate).

Clearly, with some non-human species there is considerably greater sexual dimorphism than there is with humans, and so the ambiguities should be even fewer.
 

Offline JimBob

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finding out the sex of a fossil
« Reply #4 on: 01/09/2007 00:29:20 »
Is this not taking necrophilia a bit far?


A true geologic answer, George!!!!! You can tip one with us any time.

 

The Naked Scientists Forum

finding out the sex of a fossil
« Reply #4 on: 01/09/2007 00:29:20 »

 

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