• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>Darwin's heritage today >The Effects of Flower Color Transitions on Diversification Rates in Morning Glories (Ipomoea subg.Quamoclit,Convolvulaceae)
【24h】

The Effects of Flower Color Transitions on Diversification Rates in Morning Glories (Ipomoea subg.Quamoclit,Convolvulaceae)

机译：花色过渡对牵牛花多样化程度的影响（番薯科植物菊科）

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

As in many clades of flowering plants,the Quamoclit clade of morning glories (Ipomoea subgenusQuamoclit) exhibits unequal proportions of different flower colors,with pigmented species outnum-bering unpigmented species by nearly a factor of 7.We examined three possible macroevolutionaryexplanations for this pattern:(1) asymmetric transition rates between pigmented and unpigmentedflowers; (2) low transition rates preventing the flower colors from reaching equilibrium; and (3) dif-ferential diversification.In order to discriminate among these explanations,we employ the newly-developed Binary-State Speciation and Extinction (BiSSE) model,which jointly estimates transitionrates among states and the speciation and extinction rates in each state.Using maximum likelihoodand Bayesian BiSSE estimation,we find no evidence for asymmetrical transition rates.Also,BiSSEsimulations of character evolution demonstrate that there is sufficient time for the estimated transi-tion rates to produce as many or even more white species than we observe in Quamoclit,suggestingthat low-transition rates do not fully account for the paucity of white species.In contrast,we findsupport for the differential diversification hypothesis with the rate of speciation in pigmented line-ages estimated as three-fold greater than the rate in unpigmented lineages.Our analyses thus indicatethe low frequency of white-flowered morning glory species is due largely to lineage selection.Ouranalysis also suggests that estimating character transition rates without simultaneously estimatingspeciation and extinction rates can lead to greatly biased estimates of transition rates.
机译：像许多开花植物进化枝一样，牵牛花Quamoclit进化枝（Ipomoea subgenusQuamoclit）表现出不同比例的不同花色，其中有色种比无色种高出近7倍。为此，我们研究了三种可能的宏观进化解释： （1）有色和无色花之间的过渡速率不对称； （2）过渡速率低，阻止花朵的颜色达到平衡；为了区分这些解释，我们采用了新开发的二元态物种灭绝模型（BiSSE），该模型共同估算了各州之间的过渡速度以及每个州的物种灭绝率。使用最大似然法和贝叶斯BiSSE估计，我们没有发现不对称过渡速率的证据。而且，性格进化的BiSSE模拟表明，有足够的时间让估计的过渡速率产生比在Quamoclit中观察到的甚至更多的白色物种，相比之下，我们发现差异多样化假设得到了支持，其中有色系的物种形成率估计为无色素系的物种形成率的三倍。因此分析表明，白花牵牛花物种发生频率较低的主要原因是血统选择。 s还表明，在不同时估计物种形成率和灭绝率的情况下，估计字符转换率可能会导致对转换率的估计有很大偏差。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号