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Baleen whales

Michel C. Milinkovitch and Olivier Lambert
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Humpback whale
taxon links [up-->]Balaenidae [up-->]Balaenopteridae extinct icon extinct icon extinct icon extinct icon extinct icon Not MonophyleticPhylogenetic position of group is uncertain and group is not monophyleticPhylogenetic position of group is uncertain and group is not monophyletic[down<--]Cetacea Interpreting the tree
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Containing group: Cetacea


All living mysticetes are large filter-feeders although the exact means by which baleens are used vary among species (gulp-feeding for balaenopterids, skim-feeding for balaenids, and bottom ploughing for eschrichtiids).


The morphological modifications linked to filter-feeding are:

Discussion of Phylogenetic Relationships

The relationships among extinct and extant groups of mysticetes have been less extensively studied than the relationships among odontocetes. Four families are currently recognized: Balaenidae, Balaenopteridae, the Neobalaenidae (including a single extant species, the pygmy right whale, Caperea marginata), and the Eschrichtiidae (including a single extant species, the gray whale, Eschrichtius robustus).

Some molecular analyses positioned the skim-feeding balaenids (right whales) as the basal lineage of extant mysticetes (e.g., Arnason and Gulberg, 1994, 1996; Gatesy 1998). Uncertainty remains regarding the phylogenetic position of neobalaenids: Caperea might be the sister group to balaenopterids (rorquals) and Eschrichtius (gray whale) (Arnason and Gulberg 1994), or to balaenids (Gatesy 1998). This latter hypothesis is also supported by the morphological studies of McLeod et al. (1993) and Bisconti (2000).

Discussion of some problematic extinct groups

Several fossil groups of mysticetes (e.g., Aetiocetidae and Cetotheriidae) are still taxonomically problematic; it is very likely that some of them form paraphyletic groups. Systematic revisions, additional anatomical data and cladistic analyses will be required before reaching reasonable hypotheses regarding the phylogeny of these groups.

Other Names for Mysticeti


Arnason, U. and A. Gullberg. 1994. Relationship of baleen whales established by cytochrome-b gene sequence comparison. Nature 367:726-728.

Arnason, U. and A. Gullberg. 1996. Cytochrome b nucleotide sequences and the identification of five primary lineages of extant cetaceans. Molecular Biology and Evolution 13:407-417.

Barnes, L. G., Kimura, M., Furusawa, H., and Sawamura, H. 1994. Classification and distribution of Oligocene Aetiocetidae (Mammalia; Cetacea; Mysticeti) from western North America and Japan. The Island Arc 3: 392-431.

Bisconti, M. 2000. New description, character analysis and preliminary phyletic assessment of two Balaenidae skulls from the Italian Pliocene. Palaeontographia Italica 87: 37-66.

Bouetel, V. and Muizon, C. de, 2006. The anatomy and relationships of Piscobalaena nana (Cetacea, Mysticeti), a Cetotheriidae s.s. from the early Pliocene of Peru. Geodiversitas 28(2): 319-395.

Fordyce, R. E. 1981. Systematics of the odontocete whale Agorophius pygmaeus and the family Agorophiidae (Mammalia: Cetacea). Journal of Paleontology 55(5): 1028-1045.

Fordyce, R. E. 2002. Simocetus rayi (Odontoceti: Simocetidae) (new species, new genus, new family), a bizarre new archaic Oligocene dolphin from the eastern North Pacific. Smithsonian Contributions to Paleobiology 93: 185-222.

Fordyce, R. E. and L. G. Barnes. 1994. The evolutionary history of whales and dolphins. Annual Review of Earth and Planetary Sciences 22:419-455.

Gatesy, J. 1998. Molecular evidence for the phylogenetic affinities of Cetacea. pp. 63-112 in: Thewissen J.G.M. (ed.), The Emergence of Whales: Evolutionary Patterns in the Origin of Cetacea , Plenum, New York.

Kimura, T. and Ozawa, T. 2002. A new cetothere (Cetacea: Mysticeti) from the Early Miocene of Japan. Journal of Vertebrate Paleontology 22(3): 684-702.

McLeod, S. A., Whitmore, F. C., Jr., and Barnes, L. G. 1993. Evolutionary relationships and classification. pp. 45-70 in: Burns, J. J., Montague, J. J., and Cowles, C. J. (eds). The Bowhead whale, The Society for Marine Mammalogy, Special Publication, 2.

Nikaido, M., H. Hamilton, H. Makino, T. Sasaki, K. Takahashi, M. Goto, N. Kanda, L. A. Pastene, and N. Okada. 2006. Baleen Whale Phylogeny and a Past Extensive Radiation Event Revealed by SINE Insertion Analysis. Mol. Biol. Evol. 23:866–873.

Rothausen, K. 1968. Die systematische Stellung der europäischen Squalodontidae (Odontoceti, Mammalia). Paläontologische Zeischrift 42: 83-104.

Rychel, A. L., T. W. Reeder, and A. Berta. 2004. Phylogeny of mysticete whales based on mitochondrial and nuclear data. Mol. Phylogenet. Evol. 32:892–901.

Sasaki, T., M. Nikaido, H. Healy et al. 2005. Mitochondrial phylogenetics and evolution of mysticete whales. Syst. Biol. 56:77–90.

Information on the Internet

Title Illustrations
Click on an image to view larger version & data in a new window
Click on an image to view larger version & data in a new window
Humpback whale
Scientific Name Megaptera novaeangliae
Location Gerlache Strait (Antarctica)
Comments Humpback whale (Balaenopteridae).
Creator Photograph by Gerald and Buff Corsi
Specimen Condition Live Specimen
Source Collection CalPhotos
Copyright © 2001 California Academy of Sciences
About This Page

Michel C. Milinkovitch
Genetics & Evolution, University of Geneva

Olivier Lambert
Royal Institute of Natural Sciences (Belgium)

Correspondence regarding this page should be directed to Michel C. Milinkovitch at

All Rights Reserved.

Citing this page:

Milinkovitch, Michel C. and Olivier Lambert. 2006. Mysticeti. Baleen whales. Version 07 August 2006 (under construction). http://tolweb.org/Mysticeti/16024/2006.08.07 in The Tree of Life Web Project, http://tolweb.org/

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