CETACEA Quintessential Mammals? Mammalogy – EEOB 625 27 February 2004.
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Transcript of CETACEA Quintessential Mammals? Mammalogy – EEOB 625 27 February 2004.
CETACEAQuintessential Mammals?
Mammalogy – EEOB 625
27 February 2004
Origins & Evolution: Another problem in macroevolution
• Were the first cetaceans herbivores or carnivores?
• Order Condylartha: ancestor to several ungulate taxa and cetaceans
• Pakicetus: an archaeocete of the Eocene, primitive? Heterodont, Skull not telescoped
• Neomorphic structures: tail fluke, dorsal fin
Horse
Archaeocete
Odontocete
MysticeteFeldhamer 16.4, see Vaughan Fig. 13-5
Adaptive Zones of Odontoceti and Mysticeti
• Body Size, Habitat, & Feeding specializations
• Advantages & disadvantages of large size?
• Seasonal & geographic variation in zooplankton as a food resource
• Food, migration, reproduction: Why might whales (mysticetes) be quintessential mammals?
1.__________, 2 ___________, 3___________• Relative success of the two suborders
Fig. 16.7Feldhamer
McVay, Am. Sci 61:24
Phylogeny & Classification of Odontoceti and Mysticeti
• Origin and evolution of cetaceans cladogram/ phylogeny Fig. 13-9• Is Cetacea a monophyletic taxon?• Are the two suborders valid taxa?
Probably, but are sperm whales and humpback whales closely related?
Relative “success” of the two suborders
Suborder Mysticeti • Baleen: What is it?
Feeding behavior & adaptations of the 3 families:
• Balaenidae – swim & skim
• Balaenopteridae – gulp & strain
• Eschrichtiidae – strain sediments
Fig. 16.9, Feldhamer
Minke Gray
Blue
Size & shape of baleen plates
Bowhead
Fig 4. McVey
Balaenidae
Balaenopteridae
grand gulpers
Eschrichtiide
Feeds on benthic invertebrates
National Geographic
Suborder Odontoceti • Most diverse and abundant• Delphinidae ‑ 32 species, marine & freshwater (river) species• Physeteridae ‑ sperm whales and whale strandings• What about Plantanistidae?
Fig. 16.11, Feldhamer
Physeteridae
Sperm whale Nat’l Geographic, 150:722a
The End
Evolution & Systematics