Sequence alignment, building phylogenetic trees to look at evolutionary relationships.

序列排列，建立系统发观察进化关系。

The next branch on the phylogenetic tree is liverworts.

系统发上的下一个分支是苔类植物。

Studying homologous and analogous traits, evolutionary history, and other relationships among living things is called phylogenetics.

研究生物之间的同源和类似特征、进化史和其他关系被称为系统遗传学。

It's confusing, I am aware, but phylogenetics is hard.

这混淆，我明白，但系统发生学就是这么难。

And so this is the phylogenetic tree that was drawn by Darwin.

这就是尔文所绘制的系统发。

And honestly, he did have phylogenetic ideas in some of his papers, no question.

坦白说，他在一些论文中确实提出了系统发的观点，这是毋庸置疑的。

What do you mean by a phylogenetic toolkit?

你所说的“系统发工具箱”是什么意思？

This family tree diagram is called a phylogenetic tree or cladogram.

该家谱图称为系统发或分支图。

Phylogenetic analyses work best when there are lots and lots of characters.

有多字符时，系统发分析最有效。

And so phylogenetics and phylogenetic trees require speciation to have occurred.

因此，系统发学和系统发需要物种形成已经发生。

And based on these haplogroups, they used mathematical models to come up with an evolutionary, or phylogenetic, tree.

并且基于这些单倍群，他们使用数学模型构建了一个进化， 或者说系统发。

Phylogenetic trees are constructed using the principle of parsimony.

系统发是使用简约原则构建的。

When the fossil evidence didn't have all the answers, the team used a scientific technique known as phylogenetic bracketing.

化石证据不能提供所有答案时，该团队使用了一种称为系统发括号法的科学技术。

There are a number of different phylogenetics trees.

有多种不同的系统发。

It's a saurapod that was found in Brazil and you can see it right here in this phylogenetic tree.

这是一只发现于巴西的蜥脚类恐龙，你可以在右边的系统发上看到它。

And it was about the importance of phylogeny and the sort of phylogenetic component of cooperative breeding in birds.

这关乎系统发的重要性，以及鸟类合作雏中系统发成分的作用。

But a phylogenetic tree shows the evolutionary history of an organism.

但系统发展示了有机体的进化历史。

It is an interesting challenge to develop a phylogenetic tree with the fewest number of changes.

开发变化最少的系统发是一项有趣的挑战。

We use a computer program to help us develop phylogenetic trees.

我们使用计算机程序帮助我们开发系统发。

The hypothesis was plausible, but to  test if the timing actually matched up, the researchers then performed  a phylogenetic analysis.

该假设是合理的， 但为了测试时间是否确实吻合，研究人员随后进行了系统发分析。