The evolutionary history of testicular externalization and the origin of the scrotum

@article{Kleisner2010TheEH,
  title={The evolutionary history of testicular externalization and the origin of the scrotum},
  author={Karel Kleisner and Richard Ivell and Jaroslav Flegr},
  journal={Journal of Biosciences},
  year={2010},
  volume={35},
  pages={27-37}
}
This paper re-examines the evolution of the scrotum and testicular descent in the context of the recent phylogeny of mammals. The adaptive significance of testicular descent and scrotality is briefly discussed. We mapped four character states reflecting the position of testes and presence of scrotum onto recent mammalian phylogeny. Our results are interpreted as follows: as to the presence of testicondy in Monotremata and most of Atlantogenata, which represent the basal group of all eutherians… 
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