The demise of enemy release associated with the invasion of specialist folivores on an invasive tree

There is a long history of humans either intentionally or accidentally moving plant species to areas outside of their native ranges. In novel environments, populations of many of these plant species exhibit explosive population growth and spread, in part due to the absence of coevolved enemies such as herbivorous insects. However, over time such enemies can “catch-up” with their host and re-establish host-herbivore relationships. Though this phenomenon has been documented in several systems, little evidence exists on how this re-assembly of enemies results in increased levels of herbivory. In this study we focus on the case of black locust (Robinia pseudoacacia), a sparsely populated tree species when growing on undisturbed sites in its limited native range in the eastern United States but a highly invasive species, especially in disturbed environments, in most temperate world regions. We recorded folivore damage on invasive populations in five continents, including both native and inva..., , , # The demise of enemy release associated with the invasion of specialist folivores on an invasive tree

## Description of the data and file structure

-        **Ecography_script.zip - **R script of used statistical analyses with corresponding CSV files.

-        **Medzihorsky_eal_2024_Raw_data.xlsx – **MS Excel file of leaf damage estimates for every location.

Variables:

**CountryII:** CA - Canada; CZ – Czech Republic; JP – Japan; US – USA invaded range of *Robinia pseudoacacia*; US* - USA native range of *R. pseudoacacia*; NZ – New Zealand, SA – South Africa

**Locality:** name of closest city/town to sampled locality

**Year:**  year of sampling

**Date:** date of samling; DD_MM_YY

**date_ID:** number of the day in the year (1 - 365); integer

**date_ID_comp:** number of the day in the year with correction for Southern Hemisphere (applies only for New Zealand and South African localities); date_ID + 183; after exceeding 365 starts from 1)

**Tree**: number of the tree on locali...

人类有意或无意地将植物物种迁移至其自然分布范围之外的历史由来已久。在全新的环境中，诸多此类外来植物种群会呈现爆发式增长与扩散，部分原因在于其缺乏协同进化的天敌（如植食性昆虫）。然而随着时间推移，这类天敌会“追及”其宿主并重新建立宿主-植食者的共生关系。尽管该现象已在多个研究系统中被记录，但目前鲜有证据表明这类天敌的重新组装会如何提升植食水平。本研究聚焦于刺槐（*Robinia pseudoacacia*）这一物种：在其自然分布局限的美国东部原生栖息地中，它是一种种群稀疏的乔木；而在全球多数温带区域，它却成为极具入侵性的物种，尤其在受干扰环境中表现突出。我们对五大洲的入侵种群开展了食叶昆虫危害调查，涵盖原生境与入侵境……
# 专食性食叶昆虫（specialist folivore）入侵定殖消解入侵乔木的天敌释放（enemy release）效应

## 数据与文件结构说明
- **"Ecography_script.zip"**：搭载对应CSV（逗号分隔值）文件的统计分析R脚本。
- **"Medzihorsky_eal_2024_Raw_data.xlsx"**：包含所有采样点位叶片危害程度评估数据的Microsoft Excel（MS Excel）文件。

### 变量说明：
**CountryII**：国家代码，其中CA代表加拿大；CZ代表捷克共和国；JP代表日本；US代表刺槐（*Robinia pseudoacacia*）的美国入侵分布区；US*代表刺槐的美国原生分布区；NZ代表新西兰；SA代表南非。
**Locality**：采样点位附近最近的城市/城镇名称。
**Year**：采样年份。
**Date**：采样日期；格式为DD_MM_YY（日_月_年）。
**date_ID**：采样日在当年的天数（取值范围1~365），为整数型变量。
**date_ID_comp**：针对南半球采样点（仅适用于新西兰与南非点位）的校正后当年天数：即date_ID + 183，若计算结果超过365则从1重新计数。
**Tree**：采样点位上的树木编号……