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📄 第六章.htm

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<h1 align=center style='text-align:center'><span style='font-family:隶书;
color:#EFCE8F'>第六章</span><span lang=EN-US style='font-size:36.0pt;mso-ascii-font-family:
隶书;mso-fareast-font-family:隶书;color:#EFCE8F'>&nbsp;</span><span
style='font-family:隶书;color:#EFCE8F'>系统发生分析</span><span lang=EN-US><o:p></o:p></span></h1>

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<OPTION SELECTED>========= 选择章节 ==========
<OPTION VALUE="6.1.htm">6.1 分子系统发生与系统发生树
<OPTION VALUE="6.2.htm">6.2 基于距离的系统发生树构建方法
<OPTION VALUE="6.3.htm">6.3 基于特征的系统发生树构建方法
<OPTION VALUE="6.4.htm">6.4 最大似然法
<OPTION VALUE="6.5.htm">6.5 系统发生树的可靠性
<OPTION VALUE="6.6.htm">6.6 全基因组系统发生分析
<OPTION VALUE="6.question.htm">问题与练习
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<p style='line-height:150%'><span lang=EN-US style='font-size:10.5pt;
font-family:"Times New Roman";mso-font-kerning:1.0pt'>&nbsp;&nbsp;&nbsp; </span><span
style='font-size:10.5pt;mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:
"Times New Roman";mso-font-kerning:1.0pt'>系统发生（或种系发生、系统发育，</span><span
lang=EN-US style='font-size:10.5pt;font-family:"Times New Roman";mso-font-kerning:
1.0pt'>phylogeny</span><span style='font-size:10.5pt;mso-ascii-font-family:
"Times New Roman";mso-hansi-font-family:"Times New Roman";mso-font-kerning:
1.0pt'>）是指生物形成或进化的历史。系统发生学</span><span lang=EN-US style='font-size:10.5pt;
font-family:"Times New Roman";mso-font-kerning:1.0pt'>(phylogenetics)</span><span
style='font-size:10.5pt;mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:
"Times New Roman";mso-font-kerning:1.0pt'>研究物种之间的进化关系，其基本思想是比较物种的特征，并认为特征相似的物种在遗传学上接近。系统发生研究的结果往往以系统发生树（</span><span
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lang=EN-US><o:p></o:p></span></p>

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<h2 align=center style='text-align:center'><!--mstheme--><span lang=EN-US
style='font-family:隶书;color:#EFCE8F'>6.1 分子系统发生与系统发生树 </span><span lang=EN-US><o:p></o:p></span></h2>

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<h3><!--mstheme--><span lang=EN-US style='font-size:12.0pt;color:#EFCE8F'>6.1.1
分子系统发生分析 </span><span lang=EN-US><o:p></o:p></span></h3>

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<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
text-indent:21.25pt;line-height:150%'><span style='font-size:10.0pt;font-family:
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lang=EN-US style='font-size:10.0pt'>(phenotype)</span><span style='font-size:
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