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KIN FITNESS. "Pea aphids (Acyrthosiphon pisum) that are parasitized by the Braconid wasp Aphidius ervi drop from the host plant, causing their own death. These insects live in groups of close kin, and their death prevents their body from producing parasites that would then attack their siblings. Death therefore increases the individual’s inclusive fitness, or equivalently, increases the fitness of the kin group." http://www.esciencecentral.org/journals/are-internal-death-promoting-mechanisms-ever-adaptive-2329-9002.1000113.pdf View in LinkedIn

PLANTS. "Plant cells, that have, in addition to mitochondria, another endosymbiotic organelle of cyanobacterial origin, the chloroplast. Do chloroplasts play a role in the regulation of plant programmed cell death? And since an AP-ATPase, a metacaspase and a TIR domain have been identified in cyanobacteria (as in some other bacterial lineages), did plants acquire their putative homologues of the apoptotic machinery through this endosymbiotic process?" http://www.nature.com/cdd/journal/v9/n4/full/4400950a.html View in LinkedIn

CLUSTERING VS ENCODING. "The mitochondria appear to be a locus of clustering of several of the main players in the execution and regulation of programmed cell death. Interestingly, all these players, whether located inside the mitochondria or on its outer surface, are encoded by nuclear genes, and none by mitochondrial genes." (Streamlining of endosymbiont ensured this when the engulfed bacteria transferred most of its genes to the host nucleus). http://www.nature.com/cdd/journal/v9/n4/full/4400950a.html View in LinkedIn

START OF THE STORY. "In favorable environmental conditions, Bacillus subtilis undergoes vegetative growth through symmetrical cell division. In adverse environmental conditions, such as nutrient shortage, Bacillus subtilis undergoes a complex developmental program whose initiation depends, as mentioned above, on cell density and on the concentration of released quorum factors. When initiated, this program begins with a process of asymmetric cell division." http://www.nature.com/cdd/journal/v9/n4/full/4400950a.html View in LinkedIn

KEY CAVEAT. "A cell suicide program will become counterselected unless it is regulated in such a way that the sacrifice of some individuals in a unicellular colony will benefit (or at least will not prevent) the survival of other members of the colony." http://www.nature.com/cdd/journal/v9/n4/full/4400950a.html View in LinkedIn

DRUNKARD'S WALK. "Gould argued that the average complexity of life forms has barely increased over the course of the history of life, even as the upper bound of complexity was being pushed upwards, perhaps for purely stochastic reasons, under a “drunkard's walk” model of evolution." http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn

0 https://www.thisiscolossal.com/2018/10/fruit-carving-by-takehiro-kishimoto/ View in LinkedIn

EPISODIC AMPLIFICATION. "Quantitatively, the evolution of genomes appears to be dominated by reduction and simplification, punctuated by episodes of complexification." http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn

UNHOLY ALLIANCE. "It is interesting to think that the genetic modules that are now involved in the regulation of what we call 'altruistic' regulated programmed cell death may have initially emerged and become selected as 'selfish genetic modules', for the sole reason that encoding an executioner and an inhibitor of the executioner just made them good at propagating themselves." http://www.nature.com/cdd/journal/v9/n4/full/4400950a.html View in LinkedIn

TWO PHASES OF EVOLUTION. "These and many other cases of reductive evolution are consistent with a general model composed of two distinct evolutionary phases: the short, explosive, innovation phase that leads to an abrupt increase in genome complexity, followed by a much longer reductive phase, which encompasses either a neutral ratchet of genetic material loss or adaptive genome streamlining." http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn