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SO ENDS this small collection of observations on spider webs. The focused human mind, armed with specific testable hypotheses and open curiosity, has the capacity to pierce the veil of nature. The craft of deep and careful systematic observation was exemplified by Darwin, who collected facts on a wholesale basis, both great and small, as a pointalistic collage of the nature of nature. Here, the humble spider is a Solomon among insects, an example of the remarkable depth of our natural world. https://lnkd.in/dnpWmev View in LinkedIn

ENERGY BOOST. "By transferring most genes other than those needed for rapidly responsive respiration to the nucleus and amplifying those few many times over (many mitochondrial genomes per organelle and many organelles per cell), eukaryotes have vastly increased the average energy available per gene expressed, protein synthesis being the cell’s greatest expense." http://www.pnas.org/content/112/33/10278.full View in LinkedIn

ALTERNATIVE SPLICING "is widely held to be an answer to the riddle of how humans can be (supposedly) more evolutionarily “advanced” than nematodes or fruit flies, say, while boasting hardly any more genes." Chew on that one. http://www.pnas.org/content/112/33/10278.full View in LinkedIn

INTRONS REFRESH. "By permitting the reassortment of exonic information, they facilitate both the production of multiple and possibly differently functional proteins from a single gene (“alternative splicing”) and the evolution of novel genes by recombination of exons from different genes (“exon shuffling”)." http://www.pnas.org/content/112/33/10278.full View in LinkedIn

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