Matters Arising | Published:

Reply to: Egg pigmentation probably has an Archosaurian origin

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Data availability

All data supporting the findings of this study are available within the paper (Fig. 1), and its Extended Data (Extended Data Fig. 1, Extended Data Table 1).

References

  1. 1.

    Shawkey, M. D. & D’Alba, L. Egg pigmentation probably has an Archosaur origin. Nature https://doi.org/10.1038/s41586-019-1282-4 (2019).

  2. 2.

    Wiemann, J., Yang, T.-R. & Norell, M. A. Dinosaur egg colour had a single evolutionary origin. Nature 563, 555–558 (2018).

  3. 3.

    Kennedy, G. Y. & Vevers, H. G. A survey of avian eggshell pigments. Comp. Biochem. Physiol. B 55, 117–123 (1976).

  4. 4.

    Gosler, A. G., Higham, J. P. & Reynolds, S. J. Why are birds’ eggs speckled? Ecol. Lett. 8, 1105–1113 (2005).

  5. 5.

    Wiemann, J. et al. Dinosaur origin of egg color: oviraptors laid blue-green eggs. PeerJ 5, e3706 (2017).

  6. 6.

    Salzer, R. & Siesler, H. W. (eds). Infrared and Raman Spectroscopic Imaging (John Wiley & Sons, 2014).

  7. 7.

    Thomas, D. B. et al. Analysing avian eggshell pigments with Raman spectroscopy. J. Exp. Biol. 218, 2670–2674 (2015).

  8. 8.

    Wiemann, J. et al. Fossilization transforms vertebrate hard tissue proteins into N-heterocyclic polymers. Nat. Commun. 9, 4741 (2018).

  9. 9.

    Mikšík, I., Paradis, S., Eckhardt, A. & Sedmera, D. Analysis of Siamese Crocodile (Crocodylus siamensis) Eggshell Proteome. Protein J. 37, 21–37 (2018).

  10. 10.

    O’Reilly, J. E. et al. Bayesian methods outperform parsimony but at the expense of precision in the estimation of phylogeny from discrete morphological data. Biol. Lett. 12, 20160081 (2016).

Download references

Acknowledgements

We thank D. E. G. Briggs for assistance with the manuscript, and M. Fabbri and J. Gauthier for suggestions.

Author information

J.W., T.-R.Y. and M.A.N. discussed Shawkey and D’Alba’s concerns. J.W. designed and performed the experiments, analysed the data, and created the figure. J.W. wrote the manuscript, which was reviewed by all authors.

Correspondence to Jasmina Wiemann.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Extended data figures and tables

Extended Data Fig. 1 Crocodylus siamensis outer and inner eggshell surfaces.

a, The outer eggshell surface (n = 1), which contains the highest pigment concentrations in eumaniraptorans is uncoloured/white. b, c, The inner eggshell surface (n = 2) shows a reddish tint (b), which reflects chorioallantoic tissues and vascularity (c) protruding into the innermost layers of the eggshell. The inner eggshell surface in b is manually cleaned of adjacent chorioallantoic tissue, whereas the inner eggshell surface in c is left untreated. Chorioallantoic tissues (c) are commonly vascularized, and therefore saturated in blood-derived haem, which represents, when dechelated, protoporphyrin. In this case, traces of protoporphyrin recovered from Crocodylus siamensis eggshell would not be homologous with eumaniraptoran eggshell protoporphyrin.

Extended Data Table 1 Information on added taxa (n = 4), catalogue numbers, ages, localities, and egg colours

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark
Fig. 1: Raman spectroscopic and statistical analysis of an eggshell pigmentation versus an egg colour signal.
Extended Data Fig. 1: Crocodylus siamensis outer and inner eggshell surfaces.

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.