自定义森林树中的节点形状和“分叉”

Question

我正在努力绘制系统发育树。

下面是一个最小的例子：

\documentclass[10pt]{article}
\usepackage{tikz}
\usepackage[edges]{forest}
\usetikzlibrary{trees,shapes,snakes}



\begin{document}
\begin{forest}
   % insert coordinates in empty node
innov/.style={
      edge label={node[auto, sloped,pos=.75,anchor=east]{#1}}
    },
delay={where content={}{shape=coordinate}{}},
where n children=0{tier=word}{},              % align nodes at bottom of tree
    for tree={
      forked edge,        % for forked edge
            s sep = 2mm,    % sibling distance
            l sep = 6mm,    % level distance
         fork sep = 3mm,    % distance from parent to branching point
              }
              [ to upper in the tree, text centered [, innov =innovation
                [species 1][species 2]]
    ]
\end{forest}
\end{document}

我想要获得的内容如下图所示。按重要性递减顺序排列：

1. 自定义应该独立于树级别
2. 叉处的实心圆圈（这代表最后的共同祖先，因此从语义的角度来看非常重要）
3. 水平线显示生物创新的出现
4. 如果可以用自定义边而不是节点来表示生物创新，那就更好了，以简化节点层次结构并使其更类似于生物意义。
5. 在 innovation 的最后一个字母和行之间留出更多空间（这不是很重要，我已经可以通过 ~ ~ 来增加这个空间了。

仅凭 1 和 2 就已经让我很开心了。

Answer 1

我认为这可以满足您的大部分需求。您可以创建节点样式dot并进行设置fork sep=-1pt（即点的半径）。该线可以是一个矩形节点，inner ysep=0pt其右侧有一个标签。

\documentclass[10pt]{article}
\usepackage{tikz}
\usepackage[edges]{forest}

\begin{document}
\begin{forest}
   % insert coordinates in empty node
innov/.style={
      edge label={node[draw, minimum height=0pt, inner ysep=0, pos=.75, label={left:#1}]{}}
    },
dot/.style={fill, circle, inner sep=0pt, outer sep=0pt, minimum size=2pt},
delay={where content={}{dot}{}},
where n children=0{tier=word}{},              % align nodes at bottom of tree
    for tree={
      forked edge,        % for forked edge
            s sep = 2mm,    % sibling distance
            l sep = 6mm,    % level distance
         fork sep = -1pt,    % subtract half of minimum size
              }
              [ to upper in the tree, text centered [, innov =innovation
                [species 1][species 2]]
    ]
\end{forest}
\end{document}

Answer 2

• “创新”增加了两个标签
• 点是单独绘制的

\documentclass[margin=3mm]{standalone}
\usepackage[edges]{forest}
\tikzset{
    dot/.style={circle, fill, inner sep=1.2pt, node contents={}},
        }



\begin{document}
    \begin{forest}
for tree={
            align = center,
      forked edge,          % for forked edge
            s sep = 2mm,    % sibling distance
            l sep = 6mm,    % level distance
         fork sep = 4mm,    % distance from parent to branching point
%
where n children=0{tier=word}{},              % align nodes at bottom of tree
delay={where content={}{shape=coordinate}{}},
              }
[ to upper in the tree
    [, label=center: -- , label=left:innovation\vphantom{p}, name=a
        [species 1]
        [species 2]
    ]
]
\path (a) ++ (0,-4mm) node[dot];    % vertical distance is equal to 4mm
    \end{forest}
\end{document}

附录： 为了使forest代码更短，可以方便地定义节点“创新”的样式，插入其两个标签。将其命名为inv：

\documentclass[margin=3mm]{standalone}
\usepackage[edges]{forest}
\tikzset{
    dot/.style={circle, fill, inner sep=1.2pt, node contents={}},
        }

\begin{document}
\newcommand\fd{3mm}  % <--- new, for common determining of fork distance
    \begin{forest}
for tree={
        align = center,
  forked edge,          % for forked edge
        s sep = 2mm,    % sibling distance
        l sep = 6mm,    % level distance
     fork sep = \fd,    % distance from parent to branching point
   inv/.style = {label=center:--,label={[yshift=0.4ex]left: #1~~}},  % <-- new
%
where n children=0{tier=word}{},              % align nodes at bottom of tree
delay={where content={}{shape=coordinate}{}},
              }
[ to upper in the tree
    [, inv=innovation, name=a
        [species 1]
        [species 2]
    ]
]
\path (a) ++ (0,-\fd) node[dot];    % vertical distance is equal to fork sep
    \end{forest}
\end{document}