Domain:  Eukarya
Kingdom:  Animalia
Phylum:  Chordata
Class:  Mammalia
Order:  Cetacea
Family:  Physeteridae
Genus:  Physeter
Species:  Physeter macrocephalus

Eukarya. This taxonomic group is separated by its distinct nucleus as well as other membrane bound organelles. Other organisms in this group include the tiger shark.

Animalia.  The kingdom Animalia separates itself by being multicellular, heterotrophic organisms that lack a cell wall. As well as possessing other unique characteristics such as a digestive tract and special cell junctions in their tissues.  Other organisms in this group include Green Humphead Parrotfish.

Chordata.  Animals belonging in the Phylum Chordata possess a notochord which is a hollow nerve chord located on the dorsal side of the body. Other organisms in this group include the Grizzly Bear.Sperm whales are located in the Chordata portion of this phylogenetic tree.

Figure 1.          In the above figure, Physeter macrocephalus can be found in the phylum Chordata. All of the organisms in this group share the common trait of having a notochord, or a backbone. Physeter macrocephalus has a most recent common ancestor, according to this phylogenetic tree, with Echinodermata. Some organisms that are included in Echinodermata are sea stars and sea cucumbers.  

Mammalia. All mammals possess three specific characteristics. Each mammal has hair, three middle ear bones, and produces milk from mammary glands.  Other organisms in this group include the Plains Zebra.

Cetacea. Means large sea animal in Latin and is used to describe the group that contains whale, dolphins, and porpoises. Other Organisms in this group include the Ganges River Dolphin.

 Physeteridae. This family includes all the toothed whales such as the genus Physeter, as well as the genus Kogia.  Only three species in this family are currently living. There were other animals in this family sometime in the past. We know of these animal’s existence due to fossil evidence.Phylogenetic tree for evolution of sperm whales

Figure 2.
       In the above Phylogenetic tree, Physeter macrocephalus is located in the Physeteridae family. This family contains all of the different types of sperm whales. Physeteridae shares a most recent common ancestor with the Balaenopteridae, or the finned whales. This information was found at

Physeter.  This is the genus which contains all of the sperm whale species. Physeter means blower which generally refers to how whales will exhale water vapor out of their lungs when they surface.

Physeter macrocephalus. Macrocephalus is an older term used to describe somebody with a large head. So, when scientifically naming this organisms, since it has the largest head in any of the four oceans taking up 1/3 of the animals total length it only seemed right to name it for its large head.


I hope you enjoyed learning about the classification of Physeter macrocephalus, you may return to the home page or continue on and learn about the habitat and geography of the "Real" Moby Dick.