DEWEY DECIMAL CLASSIFICATION 21ST EDITION

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Last updated 22 January 2004

Dewey Decimal Classification 21st edition overview

DDC21 changes in some areas have been found to be complex. The major change is to the 570-590 Life sciences numbers. Changes in Life sciences affecting 10 or more records on the W.A. database are provided in a comparative table at the end of the following detailed overview. For those of you feeling strong enough please read on for details about all the changes.

Table 2 Geographic areas, historical periods, persons

Schedules 000-999

The subdivisions and citation order have been changed.

In DDC20, topics of public administration were arranged under the jurisdictions Central government, Local government, United States federal government and Specific central governments. DDC21 puts the topic first and then builds the number to bring out the jurisdiction, specific department or agency. The U.S. bias in wording and structure has been reduced. e.g.

352.094 Public admin. - Local govt. - Australia (now 351.094)

354.94 Public admin. - Central govt. - Australia (now 351.94)

370 Education

Extensively revised in that some subdivisions have been reworked and expansions provided for new topics. e.g.

370.19 Educational sociology (now 306.43)

370.19342 Policy - Equal educational opportunity (now 379.26)

560-590 Life sciences

Extensively revised, see details below.

574 Biology. Number is no longer used. Biological processes have now been classed in the span 571-575.

Selected Revisions

Schedules

004-006 Data processing - Computer science

Revised and expanded to provide for processing modes, operating systems and user

interfaces.

004.678 Internet now has its own number (was 004.67 Wide-area networks)

230 Christianity Comprehensive works have been relocated from 200. (The Bible remains in 220).

398.209 Folk literature Treated by specific continent, country, locality.

508.2 Seasons (Now has its own number, was 508 Natural history).

781.64 Western popular music New subdivisions added for ragtime, reggae & rap.

796.22 Skateboarding (Now has its own number, was 796.21).

810-890 Literature. Literary periods updated and expanded.

940-990 General history of modern world. Updated to include changes in administrations and forms of government, e.g. Czech Republic and Slovakia (was Czechoslovakia).

Periods added for Australia under 994.06 - (1966-1999)

994.064	1983-1991

994.065	1991-1999

994.07	2000-        

947 Eastern Europe - Russia

947.5-.9 Countries of former Soviet Union other than Russia

Detailed Description of 570s-590s

Within the 570s-590s topics on organisms, there has been a shift in emphasis from organism+part or process (i.e. anatomy and physiology), to part or process+organism.

To quote Dewey V.4 p.1114

'The main point to remember in classifying works that treat both a specific biological subject and a specific kind of organism is that the subject takes precedence in 571-575'... (anatomy and physiology), ...'while the organism takes precedence in the rest of biology. Comprehensive works on subjects other than internal processes and structures' ... (i.e. anatomy and physiology) ... 'are classed in 576-578, while works on these other subjects, limited to specific kinds of organisms are classed with the kind of organism in 579-590'.

Examples include:

Animal physiology (comparative) was 591.1 (now 571.1).

Animal reproduction (comparative) was 591.16 (now 571.81).

Specific physiological systems in specific kinds of animals can be highlighted by adding on numbers from the 590s to some numbers in the 573s.

eg. Mammal locomotion 573.7919 is arrived at by adding 19 to the number for animal locomotion 573.79

Comparative works on the descriptive biology of organisms is now classified in the 578 numbers. This encompasses topics such as adaptation, dangerous or beneficial organisms, and organisms of specific kinds of environments.

eg. Harmful organisms was 574.65 - now 578.65

Other types of changes include:

Topics moved from one number to another

e.g. Myrtles (plants) was 583.42 - now 583.76

The new numbers may also be further divided, e.g. there is now a specific number for Eucalypts at 583.766

Topics moved from one number to another, with further subdivisions, e.g. Cats was 599.74428 - now 599.75 (general)

599.7524 (cougar, mountain lion, panther, puma)

599.7526 (European wildcat)

599.753 (lynx)

599.752 (ocelots, servals)

599.7536 (bobcat, wildcat)

599.755 (jaguar, works on big cats)

599.7554 (leopard)

599.7555 (ounce, snow leopard)

599.756 (tiger)

599.757 (lion)

599.759 (cheetah)

Items relating specifically to ecology (DDC20 574), i.e. interrelationships among organisms in types of environments are now classified in 577. e.g.

Forest ecology was 574.52642 (now 577.3 38)

Desert ecology was 574.52652 (now 577.54)

Hopefully this overview will provide some idea of the overall philosophy of the changes from DDC20 to DDC21 in the 570s-590s. Changes in the 570s-590s affecting 10 or more records on the W.A. database are provided in the table below. DDC20 and new DDC21 numbers are given.

570-599