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| Q & A |
| Brook Trout or Char |
| Question |
| I have read that our native "brookie" is not a true trout but a char.
I have been trying unsuccessfully to discover the difference. Can you explain? |
| Answer |
| Scientific classification and taxonomy of fishes, at times, can be somewhat confusing.
It is sometimes helpful when you understand the history that lead to the development of the current scientific classification
system. There are two distinct taxonomic systems currently in vogue among professional biologists today. The traditional,
or Linnaean, taxonomy is still largely in favor among field workers, conservationists, and husbandry people. The alternative,
Cladistic taxonomy, is overwhelmingly supported by evolutionary biologists.
The undisputed father of taxonomy
was the Swedish botanist Karl von Linné (1707-1778). Because virtually all science in the 18th century was
written in Latin, von Linné is better known by his Latinized name, Carolus Linnaeus. Linnaeus created the system
of scientific nomenclature still in use today, wherein every species is given two Latin names, a genus, or group name,
and the species name. Over time, biologist added additional, larger and higher level group names, called taxons (plural:
taxa), from Family up to Kingdom, arranged in a hierarchical order, until a standardized 7-level hierarchy was established,
as follows:
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Brook Trout |
| Kingdom |
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Animalia |
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Phylum |
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Vertebrata |
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Class |
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Osteichythes |
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Order |
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Salmoniformes |
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Family |
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Salmonidae |
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Genus |
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Salvelinus |
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Species |
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fontinalis |
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| Every living thing is biologically classified using this taxonomy system. The
original purpose of taxonomy was the recognition, categorization, and identification of organisms. Species were placed
into groups based primarily by apparent resemblance, shared traits or evolving within similar habitat. In Pennsylvania,
the fish we refer to as trout are all grouped under the family known as Salmonidae. However, they are each very different
from one another and further grouped under their Genus names. In North America, there are several genus of fish within
the Salmonidae family, some of which look nothing like what we think of as “trout.” |
| Family: |
Salmonidae |
| Genus: |
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Coregonus (Ciscos) |
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Prosopium (Whitefish) |
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Oncorhynchus (Pacific Salmon) |
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Salvelinus (Char) |
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Thymallus (Grayling) |
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Salmo (true trout) |
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| The confusion usually comes when we use the common name of a species and attempt
to group them using the common names. For example, the rainbow trout is actually scientifically classified as a pacific
salmon because it is more closely related to chinook, chum and sockeye salmon, which have evolved in the watersheds
that drain into the Pacific Ocean. In your example, the brook trout is actually classified as a char because it biologically
is has traits more closely related to other species of char, which have generally evolved in more northern latitudes,
colder water temperatures and at higher elevations. Other members of the Salvelinus (Char) genus are lake trout, bull
trout, and arctic char. To compound matters even more, the Atlantic salmon is scientifically classified as a true-trout
being more closely related to the brown trout than either salmon or char.
It is important to keep in mind that the common names we use for fishes have very little to do with how they are
classified in the biological world. We use common names to maintain a distinction from similar fishes, and not to
put them into distinct biological groups. |
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