Significance of the Past LArge Semiaquatic Herbivores:
evolutionary history of a polyvalent ecological niche within Cetartiodactyla

A dive into 40 million years of evolution for an ecosystem engineer niche:
the large semiaquatic herbivores within Hippopotamoidea

Principal investigators

Type of project

SPLASH is a collaborative research project of the French National Agency for Research, 2016-2021.

Research question

SPLASH depicts the evolutionary history (diversity, relationships and ecology) of hippopotamuses and of their extinct ancestors. We notably focus on the role of amphibious habits in this history, in order to enlighten hippopotamoid affinities with whales, dolphins, and porpoises, as well as their impact on past wet habitats.

Some results

SPLASH described and/or revised the mateial of a dozen of fossil forms, defined a new clade (the Merycopotamini) and unearthed a new species, Chororatherium roobii, witnessing the last step that led to extant hippos. In terms of ecology, the most striking published result is the first description of the auditory organ in partially aquatic fossil cetaceans, indicating that these animals had a morphology and auditory abilities close from terrestrial forms, and differing from that of semiaquatic hippopotamoids.


The consortium SPLASH includes PALEVOPRIM (project coordination) and the Institute of Evolutionary Sciences of Montpellier involving ten scientists (including two SPLASH postdocs), field missions (notably in the Oligocene of Kenya) and many study missions in European, African, and American museums.

Find out more

Iconic publications

Boisserie, J.-R., Kiarie, C., Lihoreau, F., Nengo, I. (2016) Middle Miocene Kenyapotamus (Cetartiodactyla, Hippopotamidae) from Napudet, Turkana Basin, Kenya. Journal of Vertebrate Paleontology 37 (1), 1-12.

Lihoreau, F., Alloing-Seguier, L., Antoine, P.-O., Boisserie, J.-R., Marivaux, L., Métais, G. and Welcomme, J.-L. (2016) Enamel microstructure defines a major Paleogene hippopotamoid clade: the Merycopotamini (Cetartiodactyla, Hippopotamoidea). Historical Biology 29 (7), 947-957.

Boisserie, J.-R., Suwa, G., Asfaw, B., Lihoreau, F., Bernor, R., Katoh, S. and Beyene Y. 2017. Basal hippopotamines from the upper Miocene of Chorora, Ethiopia. Journal of Vertebrate Paleontology 37 (3), 1-12.

Mourlam, M.J., Orliac, M.J. 2017. Infrasonic and ultrasonic hearing evolved after the emergence of modern whales. Current Biology 27 (12), 1776-1781.

Otero, O., Garcia, G., Valentin, X., Lihoreau, F., Manthi, F., Ducrocq, S. (2017). A glimpse at the ectotherms of the earliest fauna from the East African Rift (Lokone, late Oligocene of Kenya). Journal of Vertebrate Paleontology 37 (3), 1-8.



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