Interesting litter. Had the female been bred in the past? Could be a case of multiple paternity via sperm retention. Seems to be fairly common in the animal world (we have learned a lot using DNA data).

Paper:
www.seaturtle.org/PDF/Uller_2008_MolEcol.pdf
www.herpconbio.org/Volume_5/Issue_1/Wusterbarth_etal_2010.pdf

Thanks for sharing!
Chris
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Christopher E. Smith
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