Axelle ZACAÏ

Postdoctoral researcher

Main research question

I am interested in the study of biogeographical patterns of fossil organisms, and their variation in space and time as a function of climate and environmental change.

Topics of study

So far, I have applied this deep time macroecological approach to groups of marine organisms from the early Paleozoic and Mesozoic, namely:

  • the Pliensbachian ammonites of the Western Tethys (faunal similarity, phylogenetic conservatism of species range size, Rapoport effect) ;
  • the early Palaeozoic acritarchs (empirical and modelling approach of the latitudinal distribution of diversity, as a function of climate).

I will soon apply these approaches to terrestrial Neogene mammals as part of the ASAP project.

Project management

  • My contribution in PALEVOPRIM projects corresponds to the scope of the ANR ASAP.

Find out more


Iconic publications

Balseiro, D., Bignon, A., Zacaï, A., & Serra, F. (in prep). Extinction controls expansion and contraction of trilobite morphospace.

Axelle Zacaï, Claude Monnet, Alexandre Pohl, Grégory Beaugrand, Gary Mullins, David M. Kroeck and Thomas Servais, 2021 – Truncated bimodal latitudinal diversity gradient in early Paleozoic phytoplankton – Science Advances (2021) Vol. 7, no. 15, eabd6709 –

Kröck, D.M., Blanchon, M., Zacaï, A., Navidi Izad, N., Benachour, H., Monnet, C., Raevskaya, E., Szczepanik, Z., Servais, T., 2020 – Revision of the Cambro-Ordovician acritarch genus Vulcanisphaera Deunff, 1961. Review of Palaeobotany and Palynology, 279.

Zacaï, A., Brayard, A., Fara, E., Laffont, R., Dommergues, J.-L. & Meister, C., 2018 – The Rapoport effect and the climatic variability hypothesis in Early Jurassic ammonites. Palaeontology, 61(6), 963-980.

Zacaï, A., Fara, E., Brayard, A., Laffont, R., Dommergues, J.-L. & Meister, C., 2017 – Phylogenetic conservatism of range sizes is the combined outcome of phylogeny and environmental stability. Journal of Biogeography, 44(11), 2451-2462.

Zacaï, A., Brayard, A., Dommergues, J.-L., Meister, C., Escarguel, G., Laffont, R., Vrielynck, B. & Fara, E., 2016b – Gauging scale effects and biogeographical signals in similarity distance decay analyses: an Early Jurassic ammonite case study. Palaeontology, 59(5), 671-687.

Zacaï, A., Vannier, J., & Lerosey-Aubril, R., 2016a – Reconstructing the diet of a 505-million-year-old arthropod: Sidneyia inexpectans from the Burgess Shale fauna. Arthropod structure & development, 45(2), 200-220. asd.2015.09.003

Pacton, M., Sorrel, P., Bevillard, B., Zacaï, A., Vinçon-Laugier, A., & Oberhänsli, H., 2015 – Sedimentary facies analyses from nano-to millimetre scale exploring past microbial activity in a high-altitude lake (Lake Son Kul, Central Asia). Geological Magazine, 152(5), 902-922.



Tél. : +33 (0)5 49 45 37 53

Guylaine REYNAUD

Tél. : +33 (0)5 49 45 37 26

Fax : +33.(0)5 49 45 40 17


Université de Poitiers – UFR SFA


Bât B35 – TSA 51106

6 rue Michel Brunet

86073 POITIERS Cedex 9