Phylogenetic analysis of reproductive traits OF maniraptoran theropods and its implications for egg parataxonomy

  • Zelenitsky D
  • Therrien F
  • 45


    Mendeley users who have this article in their library.
  • 32


    Citations of this article.


A phylogenetic analysis of reproductive and oological (egg) traits of theropod taxa allows determination of the sequence in which these traits evolved in Theropoda. Our results indicate that several avian reproductive traits, such as adults sitting on eggs, asymmetrical eggs, unornamented eggshell surface, and complex eggshell ultrastructure, were already present in non-avian maniraptorans, and could have evolved in more basal theropods. In addition, non-avian maniraptorans laid two eggs at a time and orientated their eggs subvertically or subhorizontally in their nests, features not retained by neornithine birds. Based on our cladistic analysis it is also possible to infer the phylogenetic affinity of ootaxa of unknown parentage: Protoceratopsidovum was laid by a maniraptoran more derived than oviraptorids, and Parvoolithus probably belonged to a Cretaceous bird. Finally, our analysis reveals that many of the high-level categories of egg parataxonomy (morphotypes and basic types) are unnatural groupings (i.e. non-monophyletic). We recommend that these high-level categories be abandoned because oofamilies are sufficient to categorize egg taxa.

Author-supplied keywords

  • Birds
  • Egg
  • Eggshell
  • Maniraptora
  • Parataxonomy
  • Reproduction
  • Theropoda

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document


  • Darla K. Zelenitsky

  • François Therrien

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free