Order Cetacea
![](images/mtm_slideshows/377098955_a00f6e93f4_b.jpg)
Southern Right WhaleFamily:Balaenidae
Photo: robdownunder@flickr.com License: Creative Commons attrib/noncom/noderiv
![](images/mtm_slideshows/800px-Humpback_Whale_underwater_shot.jpg)
Humpback WhaleFamily:Balaenopteridae
Photo: NOAA@Wikimedia Commons License: Public Domain
![](images/mtm_slideshows/1427773504_6effa88bdd_b.jpg)
Humpback WhaleFamily:Balaenopteridae
Photo: Michael Dawes@flickr.com License: Creative Commons attrib/noncom
![](images/mtm_slideshows/287053455_ffc99c7c50_b.jpg)
Humpback WhaleFamily:Balaenopteridae
Chin with barnacles. Photo: zorankovacevic@flickr.com License: Creative Commons attrib/noncom/sharealike
![](images/mtm_slideshows/2854926_6b950037d4_b.jpg)
Humpback WhaleFamily:Balaenopteridae
Photo: SparkyLeigh@flickr.com License: Creative Commons attrib/noncom/noderiv
![](images/mtm_slideshows/2851875_7e18ce474d_b.jpg)
Gray WhaleFamily:Eschrichtiidae
Photo: SparkyLeigh@flickr.com License: Creative Commons attrib/noncom/noderiv
![](images/mtm_slideshows/2336943467_f0cc7c3a1b_b.jpg)
Gray WhaleFamily:Eschrichtiidae
Photo: Minette Layne@flickr.com License: Creative Commons attrib/noncom
![](images/mtm_slideshows/172439911_dea9a8a875_o.jpg)
DolphinsFamily:Delphinidae
Playing in surf. Photo: ms4jah@flickr.com License: Creative Commons attrib/noncom
![](images/mtm_slideshows/136389932_5863acbf21_b.jpg)
DolphinFamily:Delphinidae
Photo: Leo Reynolds@flickr.com License: Creative Commons attrib/noncom/sharealike
![](images/mtm_slideshows/255115491_55e06e7791_b.jpg)
OrcaFamily:Delphinidae
Photo: SparkyLeigh@flickr.com License: Creative Commons attrib
![](images/mtm_slideshows/3004847_321d878f21_b.jpg)
OrcaFamily:Delphinidae
Photo: SparkyLeigh@flickr.com License: Creative Commons attrib/noncom/noderiv
![](images/mtm_slideshows/2523819797_1e173da01a_o.jpg)
Finless Black PorpoiseFamily:Phocoenidae
Photo: ori2uru@flickr.com License: Creative Commons attrib
![](images/mtm_slideshows/2575158420_49d830d4db_o.jpg)
BelugaFamily:Monodontidae
With calf. Photo: eyesplash Mikul@flickr.com License: Creative Commons attrib/noncom
![](images/mtm_slideshows/2711746587_f895679c36_b.jpg)
BelugaFamily:Monodontidae
Photo: akahodag@flickr.com License: Creative Commons attrib/noncom/noderiv
![](images/mtm_slideshows/18229092_b29c499409_b.jpg)
BelugaFamily:Monodontidae
Photo: sillydog@flickr.com License: Creative Commons attrib/noncom/sharealike
![](images/mtm_slideshows/800px-Narwhals_breach.jpg)
NarwhalFamily:Monodontidae
Showing "tusks": enlarged upper incisors. Photo: NIST@Wikimedia Commons License: Public domain
![](images/mtm_slideshows/296886504_57a94ed8c2_b.jpg)
Sperm WhaleFamily:Physeteridae
Photo: pablo caceres c@flickr.com License: Creative Commons attrib/noncom/noderiv
![](images/mtm_slideshows/800px-Inia.jpg)
Amazonian River DophinFamily:Iniidae
With a Plecostomus Photo: Dennis Otten@Wikimedia Commons License: GNU Free Documentation License
11 Families, 84 Species
Whales, dolphins, porpoises
Worldwide
Pectoral appendages modified as fins, nostrils on dorsal surface of head
20 to 200,000 kg.