Pregnant Females as Historical Individuals: An Insight From the Philosophy of Evo-Devo

Abstract

Criticisms of the “container” model of pregnancy picturing female and embryo as separate entities multiply in various philosophical and scientific contexts during the last decades. In this paper, we examine how this model underlies received views of pregnancy in evolutionary biology, in the characterization of the transition from oviparity to viviparity in mammals and in the selectionist explanations of pregnancy as an evolutionary strategy. In contrast, recent evo-devo studies on eutherian reproduction, including the role of inflammation and new maternal cell types, gather evidence in favor of considering pregnancy as an evolved relational novelty. Our thesis is that from this perspective we can identify the emergence of a new historical individual in evolution. In evo-devo, historical units are conceptualized as evolved entities which fulfill two main criteria, their continuous persistence and their non-exchangeability. As pregnancy can be individuated in this way, we contend that pregnant females are historical individuals. We argue that historical individuality differs from, and coexists with, other views of biological individuality as applied to pregnancy (the physiological, the evolutionary and the ecological one), but brings forward an important new insight which might help dissolve misguided conceptions.

Methodology for the metaphysics of pregnancy

“…Howes, 2008) and from the perspective of biological individuality and organismality (e.g. Grose, 2020& Nuño de la Rosa et al, 2021. All these endeavours are affected by the same kinds of methodological issues that I address here, namely how our philosophical theories relate to the empirical facts as delivered by current sciences.…”

“…and that a pluralist approach may be appropriate whereby there is more than one correct answer to the question of a foetal-gestator relationship (see e.g. Nuño de laRosa et al, 2021).…”

One or two? A Process View of pregnancy

“…In contrast, Grose ( 2020 : 1050) argues that an evolutionary account of pregnancy “yields the clear verdict that there are two organisms”. Nuño de la Rosa et al ( 2021 ) approach the question of biological individuality in pregnancy from a different perspective that draws on evo-devo studies of eutherian reproduction, and conceptualise pregnant females as so-called historical individuals.…”

“… 46 See Howes ( 2007 , 2008 ) for a scientifically informed discussion of the immunological relationship between gravida and foster that reveals the generally cooperative character of their interaction and emphasises the active and constructive contributions the gravida makes towards pregnancy, in contrast to the predominant immunological ‘foreign-foetus model’, according to which the gravida is antagonistically inclined towards the foster and prevented from expelling it only through a separating immunological barrier. Nuño de la Rosa et al ( 2021 ) offer a compelling critique of common accompanying hypotheses on the evolution of pregnancy such as ‘invasive placentation’ and ‘parent–offspring conflict’ due to conflicting genetic interests. …”

“… 51 In emphasising asymmetry, my processual analysis of the relation between gravida and foster differs from Martinez Quintero and De Jaegher’s ( 2020 : 7) portrayal of pregnancy as an ‘emergent relational organisation’ which entails that both— “maternal body and embryo”, qua “processes of individuation”,—“depend on this relation for their existence as long as the relation holds”. Note that asymmetry does not hinder conceiving of the foster-gravida relation as constituting a new metastable state (Martinez Quintero & De Jaegher, 2020 : 2, 7n9) or “a novel homeostatic state defined at the relational level” (Nuño de la Rosa et al, 2021 : 7). Interactions in which one of the interaction partners takes the lead can be perfectly stable—‘stable’ in the processual sense of being the result of continuous stabilisation through interaction.…”