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FRAGMENT FROM NATURE concludes this weekend on the contemplation of biological complexification during evolution, with a focus on reductive evolution in genomes. It is generally thought that evolution always leads to greater complexity. But new evidence suggests that bursts of genetic complexification tend to be followed by long periods of genetic streamlining and loss of genes. This is not just true of parasites and symbiotic creatures, but surprisingly, also of eukaryotes. View in LinkedIn

"AGING evolved first to promote demographic stability." http://joshmitteldorf.scienceblog.com/2013/07/22/evolution-of-evolution-and-evolution-of-death/ View in LinkedIn

ACCELERATION OF EFFICIENCY. "Evolution has bootstrapped its own process, creating the conditions that lead to more efficient evolution. Some biologists find this surprising, but it has undoubtedly occurred. Among the traits that lead to more efficient evolution is aging." http://joshmitteldorf.scienceblog.com/2013/07/22/evolution-of-evolution-and-evolution-of-death/ View in LinkedIn

LIFE AS A CURVE. "This biological observation, that the empirically determined specific growth rate appears to decay proportionally with time, yields a simple model of growth, according to which the organism grows by some fundamentally exponential process, which undergoes the observed decay over its whole range." https://muse.jhu.edu/chapter/275818 View in LinkedIn

INNOVATIVE BURSTS. "Substantial increase in protein complexity appears to be associated only with the onset of the evolution of the two kingdoms of multicellular eukaryotic organisms, plants, and animals." http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn

SIGMOID CURVE. "In fact, all cells can do is divide, produce products of differentiation, migrate or remain in place, and die, but the combination of these activities over the course of time are described by a curve. Remarkably, for the years between puberty and senescence, this curve for human beings parallels the Gompertzian exponential." https://muse.jhu.edu/chapter/275818 View in LinkedIn

EUKARYOTE LOSSES. "Even more striking conclusions were reached by the reconstruction of the evolution of the eukaryotic protein domain repertoire that involved comparison of 114 genomes. The results of this reconstruction indicate that most of the major eukaryotic lineages have experienced a net loss of domains that have been traced to the LECA." (LECA = last eukaryotic common ancestor). http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn

NORMATIVE LITTLE DEATHS. "One can now list the number of times particular tissues are replaced in one year: lining of the small intestine; lining of the stomach; epidermal covering of the lips; hepatocytes of the liver; lining of the trachea; and lining of the bladder. And all this replacement is perfectly normal and not a consequence of trauma. Ultimately, biologists recognized the role of cells in death as well as life: a living thing dies when its cells no longer develop or maintain it." https://lnkd.in/dTkk9-R View in LinkedIn

WIDESPREAD LOSS. "Even animals and plants, the eukaryotic kingdoms that seem to be the least prone to gene loss, have lost about 20% of the putative ancestral genes identified in the unicellular Naegleria. Collectively, these findings imply that the genome of the LECA was at least as complex as the genomes of typical extant free-living unicellular eukaryotes." (LECA = last eukaryotic common ancestor). http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn

PATHWAY? "Death is not the waste of life it sometimes seems, but the pathway through which energy flows through virtual life and through its fractals." (Whatever that means). https://muse.jhu.edu/chapter/275813 View in LinkedIn