BACKGROUND:Our aim is to understand the evolution of species-rich plant groups that shifted from tropical into cold/temperate biomes. It is well known that climate affects evolutionary processes, such as how fast species diversify, species range shifts, and species distributions. Many plant lineages may have gone extinct in the Northern Hemisphere due to Late Eocene climate cooling, while some tropical lineages may have adapted to temperate conditions and radiated; the hyper-diverse and geographically widespread genus Hypericum is one of these. RESULTS:To investigate the effect of macroecological niche shifts on evolutionary success we combine historical biogeography with analyses of diversification dynamics and climatic niche shifts in a phylogenetic framework. Hypericum evolved cold tolerance c. 30 million years ago, and successfully colonized all ice-free continents, where today ~500 species exist. The other members of Hypericaceae stayed in their tropical habitats and evolved into ~120 species. We identified a 15-20 million year lag between the initial change in temperature preference in Hypericum and subsequent diversification rate shifts in the Miocene. CONCLUSIONS:Contrary to the dramatic niche shift early in the evolution of Hypericum most extant species occur in temperate climates including high elevations in the tropics. These cold/temperate niches are a distinctive characteristic of Hypericum. We conclude that the initial release from an evolutionary constraint (from tropical to temperate climates) is an important novelty in Hypericum. However, the initial shift in the adaptive landscape into colder climates appears to be a precondition, and may not be directly related to increased diversification rates. Instead, subsequent events of mountain formation and further climate cooling may better explain distribution patterns and species-richness in Hypericum. These findings exemplify important macroevolutionary patterns of plant diversification during large-scale global climate change.

译文

背景:我们的目的是了解从热带向寒冷/温带生物群落转变的物种丰富的植物群的进化。众所周知,气候会影响进化过程,例如物种快速扩散,物种范围变化和物种分布。由于晚始新世气候变冷,许多植物谱系可能在北半球灭绝了,而一些热带谱系可能已经适应了温带条件并辐射了辐射。超多样性和地理分布广泛的金丝桃属植物就是其中之一。
结果:为研究宏观生态位改变对进化成功的影响,我们将历史生物地理学与系统进化框架中的多样性动态和气候位改变分析相结合。金丝桃属植物进化了耐寒性c。 3000万年前,它已成功地在所有无冰的大陆上进行了殖民,如今已存在约500种。金丝桃科的其他成员留在其热带栖息地,并进化成约120种。我们确定了金丝桃属植物的温度偏好最初变化与中新世随后的多样化速率变化之间存在15-20百万年的滞后。
结论:与金丝桃属植物进化初期的生态位变化相反,大多数现存物种发生在温带气候下,包括热带地区的高海拔地区。这些冷/温ni是金丝桃属植物的独特特征。我们得出的结论是,从进化限制(从热带到温带气候)的初始释放是金丝桃属植物中的重要新奇事物。但是,适应性景观向寒冷气候的最初转变似乎是一个先决条件,并且可能与多样化率的提高没有直接关系。相反,随后形成的山体事件和进一步的气候降温可以更好地解释金丝桃属植物的分布方式和物种丰富度。这些发现例证了大规模全球气候变化期间植物多样性的重要宏观进化模式。

+1
+2
100研值 100研值 ¥99课程
检索文献一次
下载文献一次

去下载>

成功解锁2个技能,为你点赞

《SCI写作十大必备语法》
解决你的SCI语法难题!

技能熟练度+1

视频课《玩转文献检索》
让你成为检索达人!

恭喜完成新手挑战

手机微信扫一扫,添加好友领取

免费领《Endnote文献管理工具+教程》

微信扫码, 免费领取

手机登录

获取验证码
登录