Suárez Javier
Logos - Barcelona Institute for Analytic Philosophy, University of Barcelona, Barcelona, Spain.
Egenis - The Centre for the Study of Life Sciences, University of Exeter, Exeter, UK.
Hist Philos Life Sci. 2020 Feb 26;42(1):11. doi: 10.1007/s40656-020-00305-2.
Bourrat and Griffiths (Hist Philos Life Sci 40(2):33, 2018) have recently argued that most of the evidence presented by holobiont defenders to support the thesis that holobionts are evolutionary individuals is not to the point and is not even adequate to discriminate multispecies evolutionary individuals from other multispecies assemblages that would not be considered evolutionary individuals by most holobiont defenders. They further argue that an adequate criterion to distinguish the two categories is fitness alignment, presenting the notion of fitness boundedness as a criterion that allows divorcing true multispecies evolutionary individuals from other multispecies assemblages and provides an adequate criterion to single out genuine evolutionary multispecies assemblages. A consequence of their criterion is that holobionts, as conventionally defined by hologenome defenders, are not evolutionary individuals except in very rare cases, and for very specific host-symbiont associations. This paper is a critical response to Bourrat and Griffiths' arguments and a defence of the arguments presented by holobiont defenders. Drawing upon the case of the hologenomic basis of the evolution of sanguivory in vampire bats (Nat Ecol Evol 2:659-668, 2018), I argue that Bourrat and Griffiths overlook some aspects of the biological nature of the microbiome that justifies the thesis that holobionts are evolutionarily different to other multispecies assemblages. I argue that the hologenome theory of evolution should not define the hologenome as a collection of genomes, but as the sum of the host genome plus some traits of the microbiome which together constitute an evolutionary individual, a conception I refer to as the stability of traits conception of the hologenome. Based on that conception I argue that the evidence presented by holobiont defenders is to the point, and supports the thesis that holobionts are evolutionary individuals. In this sense, the paper offers an account of the holobiont that aims to foster a dialogue between hologenome advocates and hologenome critics.
布拉和格里菲思（《生命科学史与哲学》，第40卷第2期，第33页，2018年）最近指出，全生物共生体支持者提出的大多数证据，用以支持全生物共生体是进化个体这一论点，都不得要领，甚至不足以将多物种进化个体与其他多物种组合区分开来，而大多数全生物共生体支持者并不认为其他多物种组合是进化个体。他们进一步指出，区分这两类的适当标准是适应性匹配，并提出适应性有界性概念作为一种标准，可将真正的多物种进化个体与其他多物种组合区分开来，并提供一个适当标准来挑选出真正的进化多物种组合。他们的标准带来的一个结果是，按照全基因组支持者的传统定义，全生物共生体并非进化个体，除非在极少数情况下，以及对于非常特殊的宿主 - 共生体关联而言。本文是对布拉和格里菲思论点的批判性回应，也是对全生物共生体支持者所提论点的辩护。借鉴吸血蝙蝠吸血进化的全基因组基础案例（《自然生态与进化》，第2卷，第659 - 668页，2018年），我认为布拉和格里菲思忽略了微生物组生物学本质的某些方面，这些方面证明了全生物共生体在进化上与其他多物种组合不同这一论点的合理性。我认为进化全基因组理论不应将全基因组定义为基因组的集合，而应定义为主基因组加上微生物组的一些特征之和，这些共同构成一个进化个体，我将这一概念称为全基因组的性状稳定性概念。基于这一概念，我认为全生物共生体支持者提出的证据是有针对性的，并支持全生物共生体是进化个体这一论点。从这个意义上说，本文对全生物共生体进行了阐述，旨在促进全基因组倡导者与全基因组批评者之间的对话。
