Darwin, por que procurar por design se o design na natureza é ilusão?

terça-feira, março 25, 2025

Towards negative carbon footprint: carbon sequestration enabled manufacturing of coral-inspired tough structural composites

Haoxiang Deng, Haixu Du, Ketian Li, Yanchu Zhang, Kyung Hoon Lee, Botong Zheng & Qiming Wang 

npj Advanced Manufacturing


Abstract

The increasing impacts of global warming necessitate effective mitigation strategies, with carbon sequestration emerging as a viable mid-term solution. Traditional methods focus on storing CO2 or converting it into liquid substances. However, natural processes like those found in corals demonstrate superior capabilities by transforming CO2 into robust, load-bearing solids with exceptional mechanical properties. Inspired by coral’s biomineralization, this study introduces an electrochemical manufacturing method that converts CO2 into calcium carbonate minerals around 3D-printed polymer scaffolds. This approach results in mineral-polymer composites characterized by extraordinary mechanical strength and fracture toughness, fire resistance, and crack repairability. These composites also offer structure-programmability and composition-reversibility. The scalable modular assembly of these composites supports the creation of larger-scale, load-bearing meso-structures. This manufacturing paradigm promotes negative carbon footprint practices, paving the way for sustainable engineering solutions and a more environmentally friendly future.

FREE PDF GRATIS: npj Advanced Manufacturing Sup. Info.

Darwin, o neodarwinismo é suficiente? Noble e Wilson dialogam sobre a evolução

Is Neo-Darwinism Enough?: The Noble-Wilson Dialogue on Evolution Kindle Edition

by Denis Noble (Author), David Sloan Wilson (Author), James Barham (Editor)  Format: Kindle Edition - Amazon



Is Neo-Darwinism Enough? The Noble-Wilson Dialogue on Evolution

David Sloan Wilson and Denis Noble participate in a dialogue centering around the sufficiency of a neo-Darwinian framework of biology. Does neo-Darwinism provide a reasonably complete and adequate explanation of biological phenomena? Are there any new theoretical breakthroughs that are necessary to support the framework? The point of this dialogue is for both parties to advance the best case for their position, as well as to refute the case of their Interlocutor.

Advanced Praise for Is Neo-Darwinism Enough?

Denis Noble and David Sloan Wilson agree on much of what is wrong with the Neo-Darwinian synthesis — and they agree that a lot of things are wrong — yet they part ways on whether these problems amount to an outright falsification of Darwinism (Noble's view) or a call for radically reorienting Darwinism (Wilson's view). Wherever one stands on this issue, their exchange provides an accessible and reliable guide to the unsettled state of contemporary evolutionary theory.

Steve Fuller, Professor of Social Epistemology, University of Warwick UK

Evolution might be as settled a question as any in science. For several decades, how evolution works was similarly portrayed as settled science: Darwinism was the sole credible mechanism, and there was no alternative. The Darwinian idea no longer sits on that throne. But, what is the alternative? In a fascinating dialogue, Is NeoDarwinism Enough? brings together two prominent scientists, David Sloan Wilson, and Denis Noble, to debate the Yea or Nay of the question. Anyone looking for a respectful and balanced exploration of this often contentious question will come away refreshed, better informed, and more fully equipped to decide for themselves.

J. Scott Turner, Emeritus Professor of Biology, SUNY ESF, Syracuse

Public debate over the adequacy and conceptual foundations of the neo-Darwinian synthesis, when it occurs at all, is too often marred by ideology and politics, and more generative of heat than of light. We need dialogue that is not only frank but also civil, reasonable, and well-informed. To that end, Wilson and Noble have made an important contribution.

Edward Feser, Professor of Philosophy, Pasadena City College

David Sloan Wilson is SUNY Distinguished Professor in the departments of Biology and Anthropology at Binghamton University. His research interests focus on multilevel selection theory, human evolution, and differentiation within species, populations, and individuals. Wilson received his PhD from Michigan State University. He is the author of many books, including Evolution for Everyone: How Darwin’s Theory Can Change the Way We Think About Our Lives (Delta, 2007), Does Altruism Exist?: Culture, Genes, and the Welfare of Others (Yale UP, 2015), and This View of Life: Completing the Darwinian Revolution (Pantheon, 2019).

Denis Noble is Emeritus Professor of Cardiovascular Physiology in the Department of Physiology, Anatomy, and Genetics of the Medical Sciences Division of the University of Oxford, where he held the Burdon Sanderson Chair of Cardiovascular Physiology, 1984–2004. A pioneer in computer modeling of biological organs and systems, Noble received his PhD from University College London. He is the author of several books, including The Music of Life: Biology Beyond Genes (Oxford UP, 2008), Dance to the Tune of Life: Biological Relativity (Cambridge UP, 2017), and Understanding Living Systems, with Raymond Noble (Cambridge UP, 2023).

Qual é o papel do desenvolvimento na evolução?

A development-centric perspective on pace-of-life syndromes 
Isabel M Smallegange, Anja Guenther
Evolution Letters, qrae069, https://doi.org/10.1093/evlett/qrae069
Published: 26 December 2024


Abstract

Organism responses to environmental change require coordinated changes across correlated traits, so-called syndromes. For example, animals differ in their “pace-of-life syndrome” (POLS); suites of correlated life-history, behavioral and physiological traits. But standard “gene-centric” evolutionary theory cannot explain why POLSs exist because it assumes that the expression of phenotypic traits of animals is determined by genotype-specified reaction norms; it ignores that developmental processes can bias the direction of evolution so that phenotypes no longer match genotype-by-environment interactions. Here we apply a development-centric perspective to derive new POLS hypotheses that can resolve the conflict that current POLS predictions fail to explain which species/populations are resilient to environmental change.

Keywords energy allocation, energy acquisition, trade-offs, life-history theory, density-dependence

FREE PDF: Evolution Letters 

Origem da vida: os micróbios estabeleceram a base para células complexas?

sábado, março 22, 2025

Microtubules in Asgard archaea

Florian Wollweber1,3 ∙ Jingwei Xu (许靖蔚)1,3 ∙ Rafael I. Ponce-Toledo2,4∙ … ∙ Michal Wieczorek1 ∙ Christa Schleper2 ∙ Martin Pilhofer1,5



Highlights

• Asgard archaea express tubulins related to eukaryotic α/β-tubulin and bacterial BtubA/B

• Asgard tubulins (AtubA/B/B2) assemble into canonical and non-canonical heterodimers

• Asgard tubulin heterodimers polymerize into 5 or 7 protofilament microtubules

• AtubA/B form cytoskeletal structures in Ca. Lokiarchaeum ossiferum

Summary

Microtubules are a hallmark of eukaryotes. Archaeal and bacterial homologs of tubulins typically form homopolymers and non-tubular superstructures. The origin of heterodimeric tubulins assembling into microtubules remains unclear.

Here, we report the discovery of microtubule-forming tubulins in Asgard archaea, the closest known relatives of eukaryotes. These Asgard tubulins (AtubA/B) are closely related to eukaryotic α/β-tubulins and the enigmatic bacterial tubulins BtubA/B. Proteomics of Candidatus Lokiarchaeum ossiferum showed that AtubA/B were highly expressed. Cryoelectron microscopy structures demonstrate that AtubA/B form eukaryote-like heterodimers, which assembled into 5-protofilament bona fide microtubules in vitro. The additional paralog AtubB2 lacks a nucleotide-binding site and competitively displaced AtubB. These AtubA/B2 heterodimers polymerized into 7-protofilament non-canonical microtubules. In a sub-population of Ca. Lokiarchaeum ossiferum cells, cryo-tomography revealed tubular structures, while expansion microscopy identified AtubA/B cytoskeletal assemblies.

Our findings suggest a pre-eukaryotic origin of microtubules and provide a framework for understanding the fundamental principles of microtubule assembly. 

FREE PDF GRATIS: Cell

Darwin, nós temos um grave problema epistemológico: sua teoria da evolução não pode ser matematizada!

sábado, março 08, 2025

The Reasonable Ineffectiveness of Mathematics in the Biological Sciences

by Seymour Garte 1,* Perry Marshall 2 and Stuart Kauffman 3

1 Department Pharmacology and Toxicology, School of Pharmacy, Rutgers University, Piscataway, NJ 08854, USA

2 Evolution 2.0, Oak Park, IL 60301, USA

3 The Institute for Systems Biology, Seattle, WA 98109-5263, USA

* Author to whom correspondence should be addressed.

Entropy 2025, 27(3), 280; https://doi.org/10.3390/e27030280

Submission received: 24 December 2024 / Revised: 26 February 2025 / Accepted: 5 March 2025 / Published: 7 March 2025





Abstract

The known laws of nature in the physical sciences are well expressed in the language of mathematics, a fact that caused Eugene Wigner to wonder at the “unreasonable effectiveness” of mathematical concepts to explain physical phenomena. The biological sciences, in contrast, have resisted the formulation of precise mathematical laws that model the complexity of the living world. The limits of mathematics in biology are discussed as stemming from the impossibility of constructing a deterministic “Laplacian” model and the failure of set theory to capture the creative nature of evolutionary processes in the biosphere. Indeed, biology transcends the limits of computation. This leads to a necessity of finding new formalisms to describe biological reality, with or without strictly mathematical approaches. In the former case, mathematical expressions that do not demand numerical equivalence (equations) provide useful information without exact predictions. Examples of approximations without equal signs are given. The ineffectiveness of mathematics in biology is an invitation to expand the limits of science and to see that the creativity of nature transcends mathematical formalism.

Keywords: mathematical laws; set theory; third transition

FREE PDF GRATIS: Entropy



Darwin, a ilusão de design na natureza inspira novo material no esqueleto de vidro de uma esponja do mar

quinta-feira, março 06, 2025

Auxetic behavior and energy absorption characteristics of a lattice structure inspired by deep-sea sponge

Jiaming Ma, Hongru Zhang, Ting-Uei Lee, Hongjia Lu, Yi Min Xie, Ngoc San Ha

Centre for Innovative Structures and Materials, School of Engineering, RMIT University, Melbourne 3001, Australia

Received 16 September 2024, Revised 23 December 2024, Accepted 27 December 2024, Available online 27 December 2024, Version of Record 2 January 2025.

https://doi.org/10.1016/j.compstruct.2024.118835 

Image/Imagem:

The silica skeleton of a Venus’ flower basket sea sponge (Euplectella aspergillum). Credit: RMIT University

Abstract

Auxetic metamaterials, characterized by their lateral contraction under compression, have seen notable progress in recent years, largely due to advancements in 3D printing technologies. However, their practical application remains constrained by limited design versatility, moderate improvements in negative Poisson’s ratio (NPR), and relatively low structural stiffness. To address these challenges, a bio-inspired lattice structure (BLS) has been developed, drawing inspiration from the skeletal system of deep-sea hexactinellid sponges, renowned for their exceptional energy absorption capabilities, stiffness, and mechanical properties. Although this structure exhibits auxetic behavior, a comprehensive understanding of its mechanical performance, including its auxetic properties, remains incomplete. In this study, we systematically explore the auxetic behavior, stiffness, and energy absorption properties of the BLS through a combination of quasi-static compression experiments and detailed numerical simulations using finite element analysis. The experimental results reveal that the BLS outperforms conventional auxetic structures, such as re-entrant hexagonal honeycombs, in terms of NPR, stiffness, and energy absorption capacity. Furthermore, a parametric study is conducted to evaluate the influence of geometric variations, such as member thickness and spacing, on the mechanical performance of the BLS. These findings demonstrate that the BLS has the potential to pioneer a new class of auxetic materials, offering superior mechanical properties and broad applicability in engineering fields that require enhanced energy absorption and structural stiffness under compressive loading.

Keywords

Metamaterial Negative Poisson’s ratio Bio-inspired structure Auxetic 3D printing

FREE PDF GRATIS: Composite Structures