美国哈佛大学James Mallet和Neil Rosser共同合作，近期取得重要工作进展。他们研究提出，生态性状多点基因渗入能够驱动杂交物种的形成。相关研究成果2024年4月17日在线发表于《自然》杂志上。

据介绍，杂交允许谱系之间共享适应，并可能引发新物种的演化。然而，令人信服的同源杂交物种的例子仍然很少见，因为要证明杂交在产生生殖隔离方面起着关键作用是很困难的。

研究人员将种群基因组分析与物种特异性状的定量性状位点图谱相结合，研究了Heliconius 蝴蝶杂交物种的一个案例。结果表明， Heliconius elevatus是一个与双亲同域的杂交物种，作为一个独立演化的品系已经存在了至少18万年。尽管与其中一个亲本（Heliconius pardalinus）之间的基因流动普遍且持续，使它们基因组的 99% 都发生了同质化。剩下的 1%则是从另一个亲本（Heliconius melpomene）导入的，广泛散布在H. elevatus的基因组中，形成了一个个与H. pardalinus不同的岛屿。这些分化导包含多种处于破坏性选择下的性状，包括颜色模式、翅膀形状、寄主植物偏好、性信息素和配偶选择。

总之，这些性状使H. elevatu处于自身的适应高峰，并允许与双亲共存。这一研究结果表明，物种的形成是由生态性状的引入所驱动的，而基因流的物种形成是可以通过多位点遗传结构实现的。

附：英文原文

Title: Hybrid speciation driven by multilocus introgression of ecological traits

Author: Rosser, Neil, Seixas, Fernando, Queste, Lucie M., Cama, Bruna, Mori-Pezo, Ronald, Kryvokhyzha, Dmytro, Nelson, Michaela, Waite-Hudson, Rachel, Goringe, Matt, Costa, Mauro, Elias, Marianne, Mendes Eleres de Figueiredo, Clarisse, Freitas, Andr Victor Lucci, Joron, Mathieu, Kozak, Krzysztof, Lamas, Gerardo, Martins, Ananda R. P., McMillan, W. Owen, Ready, Jonathan, Rueda-Muoz, Nicol, Salazar, Camilo, Salazar, Patricio, Schulz, Stefan, Shirai, Leila T., Silva-Brando, Karina L., Mallet, James, Dasmahapatra, Kanchon K.

Issue&Volume: 2024-04-17

Abstract: Hybridization allows adaptations to be shared among lineages and may trigger the evolution of new species1,2. However, convincing examples of homoploid hybrid speciation remain rare because it is challenging to demonstrate that hybridization was crucial in generating reproductive isolation3. Here we combine population genomic analysis with quantitative trait locus mapping of species-specific traits to examine a case of hybrid speciation in Heliconius butterflies. We show that Heliconius elevatus is a hybrid species that is sympatric with both parents and has persisted as an independently evolving lineage for at least 180,000 years. This is despite pervasive and ongoing gene flow with one parent, Heliconius pardalinus, which homogenizes 99% of their genomes. The remaining 1% introgressed from the other parent, Heliconius melpomene, and is scattered widely across the H. elevatus genome in islands of divergence from H. pardalinus. These islands contain multiple traits that are under disruptive selection, including colour pattern, wing shape, host plant preference, sex pheromones and mate choice. Collectively, these traits place H. elevatus on its own adaptive peak and permit coexistence with both parents. Our results show that speciation was driven by introgression of ecological traits, and that speciation with gene flow is possible with a multilocus genetic architecture.

DOI: 10.1038/s41586-024-07263-w

Source: https://www.nature.com/articles/s41586-024-07263-w