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FITNESS EFFECTS. "Anatagonistic Pleiotropy (AP) hypothesis and the mutation accumulation hypotheses. These hypotheses are distinguished by the early effects of genes and mutations. AP refers to traits with early positive effects that trade for or against later negative effects while mutation accumulation refers specifically to costly mutations with no fitness effect early in life." View in LinkedIn

BYPRODUCT OF ADAPTION? "Most evolutionary explanations of organismal senescence are based on individual selection or selective neutrality, and interpret senescence as a byproduct rather than an adaptation selected for its own sake." View in LinkedIn

LEAN TIME EXTENSION. "The IGF-1 signaling pathway is involved in regulating life span in several model organisms, including...nematodes, and rodents. Several loci interact in what the authors term a “survival pathway”. The authors suggest that this pathway is activated to “survive unfavorable conditions in an effort to reproduce at a later time” View in LinkedIn

GENETIC DEATH. "In several model organisms, the specific genes influencing life span have been identified and there are now numerous examples where a molecular network promotes fitness early in life only to result in senescence and decreased fitness later. These are the genetic mechanisms for the Anatagonistic Pleiotropy (AP) hypothesis." View in LinkedIn

“A PRIORI, there is no privileged level of causation.” http://rsfs.royalsocietypublishing.org/content/2/1/55 View in LinkedIn

THE ISSUE OF DIRECTIONALITY. “Must higher level biological processes always be derivable from lower level data and mechanisms, as assumed by the idea that an organism is completely defined by its genome? Or are higher level properties necessarily also causes of lower level behaviour, involving actions and interactions both ways?” http://rsfs.royalsocietypublishing.org/content/2/1/55 View in LinkedIn

A BLUEPRINT FOR LIFE? “Are organisms encoded as molecular descriptions in their genes?’ And, second, ‘by analysing the genome, could we solve the forward problem of computing the behaviour of the system from this information, as was implied by the original idea of the “genetic program” and the more modern representation of the genome as the “book of life”?...The answer to both questions was ‘no’.” https://lnkd.in/dAdQzhV View in LinkedIn

FRAGMENT FROM NATURE features the thinking of Professor Denis Nobel, the brilliant polymath Oxford University academic, in his article entitled: “A theory of biological relativity: no privileged level of causation.” Denis Nobel is an exceptional and original thinker. Enjoy these philosophical ruminations. https://en.m.wikipedia.org/wiki/Denis_Noble View in LinkedIn

LIFE SPAN VS FECUNDITY. "AP has also been tested in a long-running experiment using artificial selection for increased life span in Drosophila flies. After two years of selection, life span increased, while early fecundity declined, which corroborates the AP hypothesis. After further selection however, life span continued to rise, while fecundity also rose at all ages, including early in life." (AP = antagonistic pleiotrophy hypothesis). View in LinkedIn

NEGATIVE CORRELATION. "Various methods of preventing reproduction can extend life span, and reproductive effort is negatively correlated with life span across species." View in LinkedIn