T h e Z R o n C D T h e s a u r u s
Use the Selected Term Details or Term Information to:
Verify that the selected term is the correct one.
Determine whether a more specific or narrower term is available.
Browse for a related or more appropriate term.
Specify either an explosion or a single-term search.
Expanded Tree View or Full Tree View
Provides a hierarchical display of all the broader and narrower terms for your selected
term. Indentations show the relationships between terms in the trees.
The broader terms (more general) appear further to the left on the screen. The narrow-
er terms (more specific) appear further to the right. The numbers in the far left column
indicate the level of the heading in the tree hierarchy. Level 1 is the broadest, or least
specific, level. For each additional level, the number increases by one. There can be
more than one term at any one level. See Figure 4.
TREES: HIERARCHICAL DISPLAY OF ALL BROADER
& NARROWER TERMS
1 .. Habitat
2 ...... Interstitial habitat
3 .......... Hydrothermal vent
3 .......... Lagoon habitat
3 .......... Marine shore habitat
4 .............. Beach
4 .............. Tide pool
3 .......... Reef habitat
3 .......... Sea ice habitat
3 .......... Surf
3 .......... Marine benthic zone
4 .............. Abyssal zone
Figure 4 Expanded Tree Screen
In the example above,
Marine Habitat, at level 2, is the generic term that groups together a
number of headings which correspond to specific types of marine habitats. At level 3,
rine shore habitat is one of those specific habitats. There is an additional level in this tree;
Tide pool at level 4 is defined by its place in the tree to be a type of Marine shore habitat.
In this example, if you are interested in all marine habitats in general, you should ex-
plode that heading (level 2). The heading
Marine habitat will automatically be com-
bined with all the terms indented below it, using the
or operator. If you are only
interested in a
Marine shore habitat, then explode that heading (level 3). And, if you are
interested only in a
Tide pool habitat, conduct a single-term search on that level-4 term.
Expanded Tree View shows
you a hierarchical display
surrounding a chosen term.