Classification of the White Shark
and Selected Other Creatures
Taxonomy is the scientific art of classifying living things. Biological classification has two basic objectives:
-
to serve as a basis for generalization in comparative studies and,
- to serve as an information storage system.
The system of classification used by all biologists today is based on a hierarchical scheme devised by Swedish naturalist Carl von Linné (often Latinized to Carolus Linnaeus). In the 10th edition of his Systema Naturae (published in 1758), Linné listed every type of animal known to him, organizing them into groups based on overall similarity. The Linnaean system consists of seven major categories, called taxa (singular: taxon, meaning "rank"). Arranged from the broadest, most inclusive category, to the narrowest, most exclusive category, these taxa are:
KINGDOM,
PHYLUM,
CLASS,
ORDER,
FAMILY,
GENUS,
SPECIES.
What follows is the modern biological classification of the White Shark and, for comparison, selected other creatures. Only the seven major taxa are shown. (In practice, as many as eleven sub-taxa may be sprinkled among these major divisions, but not all of them have been defined for all groups of organisms and they need not concern us here.):
| Taxon | White Shark | Spiny Dogfish | Ling Cod | Northern Elephant Seal | Human |
| Kingdom | Animalia | Animalia | Animalia | Animalia | Animalia |
| Phylum | Chordata | Chordata | Chordata | Chordata | Chordata |
| Class | Chondrichthyes | Chondrichthyes | Actinopterygii | Mammalia | Mammalia |
| Order | Lamniformes | Squaliformes | Scorpaeniformes | Pinnipedia | Primates |
| Family | Lamnidae | Squalidae | Hexagrammidae | Phocidae | Hominidae |
| Genus | Carcharodon | Squalus | Ophiodon | Mirounga | Homo |
| Species | carcharias | acanthias | elongatus | angustirostris | sapiens |
Thus, according to current ideas of biological classification, the White Shark is as distantly related to a Ling Cod (a bony fish, belonging to a completely different class) as it is to ourselves (a mammal, belonging to yet another class).
The animals whose classifications are profiled here have been chosen because they all play a role in the White Shark story. Off the west coast of North America, the Spiny Dogfish, Ling Cod, and Northern Elephant Seal are all important prey species for the White Shark. The Northern Elephant Seal is known to eat Spiny Dogfish and Ling Cod. Both Northern Elephant Seals and the White Shark have been known to bite humans, but these injuries are generally not feeding related. Only one predator among these animals has been known to kill and eat each of the others: Homo sapiens. Yet only humans classify themselves as "not on the menu" and complain vehemently when, on rare occasion, one of these creatures turns table on us. Food for thought?
According to Nelson (1994, page 65), the long-established class Osteichthyes is clearly not a monophyletic (natural) group; he advocates splitting these so-called 'bony fishes' into two classes, Sarcopterygii (the lobe-finned fishes), and Actinopterygii (ray-finned fishes). This view has not yet been widely adopted in ichthyological classifications and thus Actinopterygii is provisionally used here in the anticipation of this view becoming more widely accepted. [Back to table]
