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INTRONS AND THE KEY TO EVOLUTION. "Spliceosomal introns might well be one of the genomic feature that eukaryotes must put up with because of small population sizes. When these genic interruptions (found in all eukaryotes but, as yet, not in prokaryotes) were first discovered, Gilbert ventured that their presence held the key to the enhanced evolutionary potential of eukaryotes." http://www.pnas.org/content/112/33/10278.full View in LinkedIn

THE SCENARIO, UNFOLDED. "Once on the scene, eukaryotes are imagined to have radically altered evolution’s tempo and mode. With cells structurally more complex—but at the same time, more self-similar at the cellular level—than their prokaryotic ancestors, eukaryotes radiated into a great diversity of organismal types, including complex multicellular forms with the transcendent potential to “bear embryos, respond to music, and reflect on their own nature” http://www.pnas.org/content/112/33/10278.full View in LinkedIn

NOT UNIQUE. "We suggest that there is no fundamental difference in kind between these various symbiotic alliances, just different evolutionary histories. Eukaryotes do not pose unique challenges to and do not require special treatment within evolutionary theory." http://www.pnas.org/content/112/33/10278.full View in LinkedIn

ON A SPECTRUM. "Eukaryogenesis is not necessarily different in kind from other symbiotic alliances that have occurred much more recently in evolutionary history, but it is a very ancient one, affected at a basic cellular level. Accordingly, it receives very high scores along each of the axes of integration. Some (but not all) of the other symbioses have lower scores along some axes." http://www.pnas.org/content/112/33/10278.full View in LinkedIn

HIGH LEVEL ALLIANCES. "Although there are some aspects of the eukaryotic condition that have not been documented in higher-level egalitarian alliances (e.g., gene transfer between partners), even these aspects are not unique to mitochondria and plastids, as both the Paulinella and “Chlorochromatium aggregatum” cases show." http://www.pnas.org/content/112/33/10278.full View in LinkedIn

MIXED COMMUNITIES. "Processes of evolution in which entities from different lineages can be bound together in the creation of new community-level reproductive individuals are not uncommon, and such symbiotic entities occur at hierarchical levels above that of the cell, sometimes among exclusively eukaryotic partners." A very fresh perspective on the old issue of the uniqueness of eukaryogenesis. http://www.pnas.org/content/112/33/10278.full View in LinkedIn

BOGUS RARITY CLAIMS. "Thus, claims about both the process and product of eukaryogenesis as being unique or as challenging contemporary evolutionary theory should at least be treated with skepticism." http://www.pnas.org/content/112/33/10278.full View in LinkedIn

PERFORMANCE DRIVERS. "Under distributed loads the stiff behaviour of silk under small deformation, before the yield point, is essential in maintaining the web’s structural integrity. The superior performance of silk in webs is therefore not due merely to its exceptional ultimate strength and strain, but arises from the nonlinear response of silk threads to strain and their geometrical arrangement in a web." https://lnkd.in/dYdY4x3 View in LinkedIn

BIASED METRICS. "However, cyanobacteria will also surely evolve differently from mycoplasmas or methanogens. What are our principled metrics for degrees of difference, and how are we sure that these are free of the sorts of eukaryocentric bias that we discuss in the next section? What is our metric for “richer evolutionary potential”." http://www.pnas.org/content/112/33/10278.full View in LinkedIn

FRAGMENT FROM NATURE continues the meditation on the flat twisted tessellations known as spider webs; between the geometric curiosities, the cunning molecular design, and the biological diversity of these structures and their inhabitants, resides a case study of the ingenious options explored by blind experimentation and natural selection for fitness. A case study that has been the illusive goal of engineers and biochemists alike. View in LinkedIn