相关实验视频
Updated: May 27, 2025
12:00
A Practical Guide to Phylogenetics for Nonexperts
Published on: February 5, 2014
35.3K
植物遗传模型中的树木平衡
Sophie J Kersting1, Kristina Wicke2, Mareike Fischer1
1Institute of Mathematics and Computer Science, University of Greifswald, Greifswald 17487, Germany.
概括
选择正确的遗传树平衡指数对于准确的进化分析至关重要. 这项研究将索引按树模型的适用性进行分组,以帮助研究人员,并引入R包poweRbal以方便选择.
科学领域:
- 人类遗传学和进化生物学
- 计算生物学 计算生物学
- 统计建模 统计建模
背景情况:
- 树形状统计,特别是树系遗传平衡的测量,对于分析进化过程至关重要.
- 存在众多 (不) 平衡指数 (超过30个),这给研究人员在选择适当的措施和避免多重测试问题方面带来了挑战.
- 应用范围包括进化模型,特征遗传,瘤发育和语言进化.
研究的目的:
- 系统地评估一套全面的已建立的家族遗传树平衡指数的力量.
- 为了确定哪些指数对不同类型的家族遗传树模型最有效,包括基于特性的模型.
- 为研究人员在选择适当的平衡指数方面提供指导,并引入新的软件工具.
主要方法:
- 扩展了以前对树木平衡指数的权力分析,包括几乎所有已知的指数.
- 纳入了更广泛的替代进化模型,包括各种基于特征的模型.
- 开发了R软件包,以促进新指数和模型的纳入.
主要成果:
- 确定了不同组的平衡指数,这些平衡指数在特定树模型中表现更好.
- 证明了基于对树模型的先前知识的平衡指数的知情选择可以增强分析决策.
- 树形统计数据的未来研究提供了一个灵活的平台.
结论:
- 遗传学平衡指数的选择对进化模型的分析产生了重大影响.
- 研究人员可以通过了解哪些平衡指数最适合不同的家族遗传树模型来改进他们的分析.
- 关于树形状分析的研究. 关于树形状分析的研究. 关于树形状分析的研究. 关于树形状分析的研究.
相关概念视频
03:21Phylogenetic Trees
45.0K
Phylogenetic trees come in many forms. It matters in which sequence the organisms are arranged from the bottom to the top of the tree, but the branches can rotate at their nodes without altering the information. The lines connecting individual nodes can be straight, angled, or even curved.
45.0K
01:23Phylogeny
43.5K
Phylogeny is concerned with the evolutionary diversification of organisms or groups of organisms. A group of organisms with a name is called a taxon (singular). Taxa (plural) can span different levels of the evolutionary hierarchy. For instance, the group containing all birds is a taxon (comprising the class Aves), and the group of all species of daisies (the genus Bellis) is a taxon. Phylogenies can likewise include just one genus (i.e., depict species relationships) or span an entire kingdom.
43.5K
02:54Evolutionary Relationships through Genome Comparisons
5.7K
Genome comparison is one of the excellent ways to interpret the evolutionary relationships between organisms. The basic principle of genome comparison is that if two species share a common feature, it is likely encoded by the DNA sequence conserved between both species. The advent of genome sequencing technologies in the late 20th century enabled scientists to understand the concept of conservation of domains between species and helped them to deduce evolutionary relationships across diverse...
5.7K
01:19Survival Tree
52
Survival trees are a non-parametric method used in survival analysis to model the relationship between a set of covariates and the time until an event of interest occurs, often referred to as the "time-to-event" or "survival time." This method is particularly useful when dealing with censored data, where the event has not occurred for some individuals by the end of the study period, or when the exact time of the event is unknown.
Building a Survival Tree
Constructing a...
Building a Survival Tree
Constructing a...
52
02:40The Tree of Life - Bacteria, Archaea, Eukaryotes
31.9K
The “tree of life” describes the evolution of life and the evolutionary relationships between organisms. The root of the tree is the common ancestor to all life on Earth. All other species radiate from this point, much like the branches of a tree. The numerous tips of these branches on the tree of life represent every living, or extant, species. Extinct species, which are species that no longer exist, can be found towards the center of the tree. Currently, these organisms, both...
31.9K
00:51Energy Budgets
9.2K
Organisms must balance energy intake with the energy required for growth, maintenance and reproduction. These trade-offs result in a variety of survivorship and reproductive strategies, including semelparity and iteroparity. Semelparous species, like annual plants, have only one reproductive episode in their lifetimes and consequently have short lifespans. Iteroparous species, by contrast, have many reproductive events during their lifetimes but have relatively few offspring. These two...
9.2K