Template:Clade/doc

This template is used for drawing branching trees with the node and base labels being clickable links. Such diagrams are especially suited to represent evolutionary trees (cladograms).

See {{Cladex}}for two extra features:

• Double lines leading to a node can be produced as easily as dotted lines.
• Brackets or bars of a chosen colour can be placed to the right of a set of leaf nodes in the cladogram, thus allowing paraphyletic groups to be identified.

Basic features

Usage

{{clade
|label1=Base
|1=Node
}}

produces

Base	Node

{{clade
|1={{clade
   |label1=[[Subtree1]]
   |1=Leaf1
   |label2=Subtree2
   |2=[[Leaf2]]
   }}
}}

produces

	Subtree1  Leaf1 Subtree2  Leaf2

{{clade| style=font-size:75%;line-height:75%
|1={{clade
   |label1=Subtree1
   |1=Leaf1
   |label2=Subtree2
   |2=Leaf2
   }}
}}

produces

	Subtree1 Leaf1 Subtree2 Leaf2

Note that the order of the parameters does not matter. Exactly the same output is produced by

{{clade| style=font-size:75%;line-height:75%
|1={{clade
   |2=Leaf2
   |1=Leaf1
   |label1=Subtree1
   |label2=Subtree2
   }}
}}

	Subtree1 Leaf1 Subtree2 Leaf2

{{clade
|1={{clade
   |1={{clade | thickness=3
      |1=Leaf1
      |2=Leaf2
      }}
   |2=Leaf3
   }}
}}

produces

	Leaf1 Leaf2 Leaf3

To replace a solid line leading to the Nth child with a dashed line, use |stateN=dashed.

{{clade
|1={{clade
   |1={{clade
      |1=Leaf1|state1=dashed
      |2=Leaf2
      }}
   |2=Leaf3
   }}
}}

produces

	Leaf1 Leaf2 Leaf3

Tips

An easy way of creating larger cladograms is to use the Newick format and proceed to edit it using a suitable text editor to produce the markup.

1. Start with Newick format ((a,b),(c,d))
2. Replace "(" with "{{clade|"
3. Replace ")" with "}}"
4. Edit to replace commas with pipes and numbers
5. Edit clade labels if needed

Alternatively, one can easily generate required clade code by downloading the free Windows utility, 'Claded', via link at http://code.google.com/p/claded, 'Claded' allowing editing of Cladograms using a tree control.

{{clade
 |1={{clade
    |1=a
    |2=b
    }}
 |2={{clade
    |1=c
    |2=d
    }}
}}

Example Perl script to automate the conversion:

use constant N=>"\n";
use constant T=>"\t";

my $tree='((a,b),(c,d));'; # get sequence
$tree=~s/[\n\r]//g; # loose those spaces
$tree=~ s/\:[\.\d]+//g; # loose those lengths
while ($tree=~ m/\(/) {
	foreach my $clade ($tree=~ m/\(([^\(\)]+)\)/g) {
		my @branches=split /\,/,$clade;
		s/(\t+)/$1\t/g for @branches;
		die 'ERROR: degenerate/empty node!'.N if $#branches<1;
		$tree=~ s/\(\Q$clade\E\)/${\join('','{{clade',N,map(T.'|'.($_+1).'='.$branches[$_].N,0..$#branches),T.'}}')}/; # substitute
	}
	pos($tree)=0;
}
$tree=~s/(\t*)\t\}\}/$1\}\}/g; # lazy fix

print $tree;

Using a box

You can nest the templates and use links around the text. You may use non-breaking spaces ( ) to obtain spaces or to have labels that have spaces.

The entire cladogram can be placed in a box so that text flows nicely around it. You can use {{Cladogram}} to produce the box. Template:Cladogram

{{cladogram|title=Example
|caption=Sample of {{tl|Cladogram}}
|clades={{clade| style=font-size:75%;line-height:75%
    |label1=[[Neornithes]]  
    |1={{clade
        |label1=[[Paleognathae]]
        |1= 
        |label2= [[Neognathae]] 
        |2={{clade
            |1=Other birds
            |label1= 
            |label2=[[Galloanserae]] 
            |2={{clade
                |1=[[Anseriformes]]
                |label2=    
                |2={{clade
                    |1=[[Galliformes]]
                    |2=[[Craciformes]]
                    }}
                }}
            }}
        }}
    }}
}}

Controlling the layout of sisters

When one sister is represented as a leaf node and the other as a labelled subclade, they do not appear to be at the same level. Consider this cladogram:

	Banksia subser. Sphaerocarpae (5 taxa) Banksia subser. Leptophyllae Banksia telmatiaea (4 other taxa)

Although Banksia subser. Sphaerocarpae and Banksia subser. Leptophyllae are sisters, their names are not aligned in the cladogram. If this is considered undesirable, one solution is to use a label in both cases, as shown below, which now shows the sisters at the same level.

	Banksia subser. Sphaerocarpae (5 taxa) Banksia subser. Leptophyllae Banksia telmatiaea (4 other taxa)

Another 'trick' is to introduce a dummy clade. The dotted line below shows where an extra clade has been inserted:

	Banksia subser. Sphaerocarpae Banksia subser. Leptophyllae Banksia telmatiaea (4 other taxa)

To achieve this, instead of

{{clade
|1=Sister1
|label2=Sister2
|2={{clade
   ...
   }}
}}

use

{{clade
|1=Sister1
|2={{clade
   |label1=Sister2
   |2={{clade
       ...
      }}
   }}
}}

Limitations

Label length

Labels produced by |labelN=, where N is 1, 2, ..., can lead to poor layout of the resulting cladogram. (This does not apply to the text of leaves, i.e. text produced by |N=.) To avoid problems:

• labels should be kept as short as possible, ideally a single word
• any necessary spaces in labels should be represented as   not as actual spaces
• line breaks (i.e. <br>) should not be used.

Browser differences

Browser variation: left – Internet Explorer, Firefox; right – Safari, Chrome, Opera

Cladograms are drawn by generating hidden tables. The horizontal and vertical lines making up the tree are actually the edges of table cells. The tables are then drawn by the browser or user agent using its internal algorithms. As these differ from browser to browser, the trees produced will not look the same on all browsers.

In particular, Template:As of there are two algorithms for laying out tables with empty cells, used by two groups of browsers. Browsers like Internet Explorer and Firefox use one algorithm, producing cladograms like the two on the left in the diagram. Browsers like Safari, Chrome and Opera use another algorithm, producing cladograms like the two on the right in the diagram.

No automated "fix" for these differences exists at present.

If there is a choice over the ordering of the terminal nodes (leaves) of the tree, cladograms look best in the second group of browsers if as much branching as possible is at the bottom of the cladogram. Typically this is produced by arranging the terminal nodes downwards on the page in order of their evolutionary divergence. Compare the bottom row of the diagram to the top row.

Large cladograms

There are limitations on the size and complexity of the cladograms which can be drawn:

• A maximum of 17 children is allowed per node. It may seem that this could easily be increased by editing the template, but see the next point.
• Cladograms can only be expanded up to a certain level of complexity because the MediaWiki software limits the resources available for template expansion. The cladogram at APG_III_system#Phylogeny has had to be broken into three parts, because the entire cladogram exhausts the allowed resources (in this case the allowed expansion depth). Any change to the template could result in large cladograms failing to display correctly. In general, don't exceed a depth of 19, i.e. don't nest one clade template inside another more than 19 times.

Inclusion in books

There are many known bugs in rendering tables in the software which produces Wikipedia books; see the book tool feedback page. Template:As of these result in the lines in cladograms not displaying in books.