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VAST RANGE. "Although mutations provide the ultimate material upon which natural selection depends, most mutations are deleterious, and in certain settings can lead to a substantial fitness load. We are attempting to understand the nearly 1000-fold range of variation in the mutation rate that exists across the Tree of Life, through the study of a diversity of invertebrates and unicellular eukaryotes and prokaryotes." http://www.bio.indiana.edu/faculty/directory/profile.php?person=milynch View in LinkedIn

DUBIOUS EQUIVALENT. "The utility of equating complexity with entropy is dubious at best as becomes particularly clear when one attempts to define genomic complexity. Indeed, using sequence entropy (Shannon information) as a measure of genomic complexity is obviously disingenuous given that under this approach the most complex sequence is a truly random one that, almost by definition is devoid of any biological information." http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn

UNWOUND THEORY. "It seems logical that organisms should acquire mechanisms that push the age of onset of ill effects from numerous minor defects associated with genetic load toward later ages. However, our analysis suggests that such mechanisms, if carried to extremes, have bad evolutionary repercussions." http://www.pnas.org/content/110/25/10141.full View in LinkedIn

EXEMPLARS OF STREAMLINING. "The mitochondria, the ubiquitous energy-transforming organelles of eukaryotes, and the chloroplasts, the organelles responsible for the eukaryotic photosynthesis, are the ultimate realizations of bacterial reductive evolution." http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn

DRIVEN TO EXTINCTION. "At a snapshot in time, hazards lie low for a stretch of ages, climb at ages where remaining net fertility is dropping off, and link up with the old-age segment. As time goes by, the climbing phase shifts down to younger and younger ages, until the hazard rate at every adult age comes to be marching toward infinity. Unbounded accumulation of mutations across the whole reproductive span drives any population to extinction." http://www.pnas.org/content/110/25/10141.full View in LinkedIn

“GENETIC OUTSOURCING is not to be confused with simplification in parasite downsizing. In many cases, access to the host genome, or simply parking of its own genetic burden can be seen as a type of genetic expansion strategy. Streamlining with greater efficiency and greater plasticitymay be a better term than simplification.” http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn

PART B. "A complementary picture emerges with respect to time. A steady influx of mutations affects the whole reproductive span. Hazards begin to increase linearly with time at all ages. At older ages, where selective pressure is always low, this linear increase continues unabated, whereas at younger ages it is slowed for a while by outflow due to natural selection." http://www.pnas.org/content/110/25/10141.full View in LinkedIn

PARASITIC SIMPLIFICATION. "It has been well known for decades that the evolution of numerous parasitic and symbiotic organisms entails simplification rather than complexification. In particular, bacteria that evolve from free-living forms to obligate intracellular parasites can lose up to 95% of their gene repertoires without compromising the ancestral set of highly conserved genes involved in core cellular functions." http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn

THE THEORY UNRAVELS. "However, if we try to construct an equilibrium with some specific wall of death, we find too little remaining net fertility very close to the wall to balance mutation there. Each wall of death implies an earlier one. The instability propagates down through the whole reproductive span, and our construction unravels." http://www.pnas.org/content/110/25/10141.full View in LinkedIn

THEORY CONTINUED. "At sufficiently advanced ages, remaining net fertility necessarily drops below any mutation rate that is bounded below. If the force of selection depends only on remaining net fertility, selection cannot balance mutation, and such ages must lie beyond a wall of death." http://www.pnas.org/content/110/25/10141.full View in LinkedIn