IAS-Research Seminars by Juli Peretó (University of Valencia) “Transmetabolism: Pushing the Limits of Biological Autonomy”

On Thursday, Dec 2nd, 2021 at 11:30

To participate, please contact: alejandra.mtz.quintero@gmail.com

Abstract: 

Living beings are the result of a cocktail made with unknown doses of chance and necessity. Consider a thought experiment, in which we could rewind the ‘tape of life’ starting from the same initial conditions, what biochemical traits and cellular features would finally be the same as those we observe today? It is clear that what is real in biology is a subset of what is possible, and this issue has been discussed at different scales. Thus, structural and dynamic developmental constraints limit the space of solutions for animal bodies (Alberch, 1989), whereas physicochemical restrictions and historical contingencies shape the possible at the molecular level (Jacob, 1981). Meteorite analysis and many organic syntheses performed under prebiotic conditions indicate that the primitive Earth was home of a moderately complicated chemodiversity, including the most common biological building blocks – sugars, fatty acids, amino acids, nucleobases, etc. (Lazcano, 2018). In this period of chemical evolution, physicochemical constraints (i.e. thermodynamics and kinetics in a given environment) determined the origin and maintenance of the abiotic chemical landscape. The chemically possible was the scenario for the organization of the most simple and primitive biochemical systems: autocatalytic cycles for self-maintenance of a set of building blocks, self-reproduction of lipid vesicles, and self-replication of genetic templates (Peretó, 2012). Presumably, all these cycles kicked off in the absence of catalysts or with the involvement of very simple and unspecific facilitators (e.g. mineral surfaces). The emergence of optimizable catalysts through natural selection (e.g. ribozymes) was a phase transition to a period of a more efficient and creative functional screening of the possible (de Duve, 2005). Diverse lines of evidence indicate that metabolic surveys of alternative sources of matter and energy were rapid and explosive, performed by the first microbial communities. Biogeochemical closing of the recycling of bioelements was a vital step for a sustainable and long-term continuity of terrestrial life (Falkowski et al., 2008). Thus, the boundaries of the metabolically possible were expanding in parallel to the coevolution of life and the planet. For instance, after the emergence in some cyanobacterial ancestors of the enzymatic machinery able to extract electrons from water to feed the photoelectronic chain, molecular oxygen accumulated in oceans and afterwards in the atmosphere. Those microorganisms able to cope with this new-to-life compound took advantage of its reactivity and dramatically expanded the world of the metabolically possible: many new metabolites, including steroids, and processes (e.g. oxygen respiration) became available to life. Thus, recurrent patterns in actual cell metabolisms are the result of a long evolutionary exploration within the chemically constrained space of the possible solutions under specific yet changing conditions (de Lorenzo et al., 2014).

Full text: https://sfamjournals.onlinelibrary.wiley.com/doi/10.1111/1751-7915.13691

“The Autonomies of Bioethics” – IAS-Research Seminar by Ion Arrieta

Date and time: 25th June 2013, at 11.00
Location: Carlos Santamaria Building, Room B14.
Speaker: Ion Arrieta
Title: The Autonomies of Bioethics
Abstract: This presentation begins with a set of distinctions between differents concepts (or families of concepts) of autonomy that are present in the theory and practice of bioethics. My porpuse is to examine how the principle of autonomy works in two different branches of bioethics, health care ethics on the one hand, characterized by the dependence of patients and users of health services, and research ethics on the other, marked by the vulnerability of the subjects. Although differents fields (health care is not a science but a practice or art, while biomedical research does aspire to be scientific), I transfer some intuitions from the first to the second field, especially those emphasizing the interactive and relational nature of autonomy. The fact that autonomy is always relational is more easily seen in healthcare ethics, but not so much in research ethics. Despite that autonomy in research ethics is more formal and less personal, I defend that it needs integrate certain aspects of healtcare, which mainly affect how we understand the autonomy of the patient or research subject in relation to the clinicians or researchers who are treating them.

“Habits as sensorimotor life-forms” – IAS-Research seminar by Matthew Egbert and Xabier E. Barandiaran

Date and Time: 11am, Tuesday 18th June, Carlos Santamaría Building, B14
Title: Habits as sensorimotor life-forms: modelling self-maintaining behaviour with an iterant deformable sensorimotor medium
Abstract: Artificial Life has not yet explored in depth the analogy between life and mind that is hidden in the nature of habits: their self-sustaining dissipative structure as ecological sensorimotor entities. We present a new dynamical model for habits implementing what we call a node-based “iterant deformable sensorimotor medium” (IDSM). The IDSM has properties designed such that trajectories taken through state space increase the likelihood that in the future, similar trajectories will be taken. We couple the IDSM to sensors and motors of a simulated body in a simulated environment and show that under certain conditions, the IDSM resonates with the other parts of the simulation, forming self-maintaining patterns of activity operating over the IDSM, the body, and the environment. These patterns of activity are similar in many respects to habits, patterns of activity that are self-reinforced. We present various environments and the resulting ‘habits’ that form in them, studying the sensorimotor coordination patterns that stabilize in the process. We discuss how this model and extensions of it can help us understand and model self-sustaining patterns of behaviour as building blocks for a theory of cognition that does no rely on representations

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