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HIGH CUE VARIABILITY. "Deceptive orchids often show high variability in floral signals, which may be maintained by negative frequency-dependent selection, since pollinators can learn and subsequently avoid common deceptive morphs more quickly than rare ones. The evolution of obligate deception in orchids seems paradoxical in the light of the typically lower fruit set than in rewarding species." http://link.springer.com/article/10.1007/s00114-005-0636-y View in LinkedIn

CANCER CELLS ARE IMMORTAL. "What allows a cancer cell to keep diving endlessly, generation upon generation? Here’s an emerging answer: The human embryo and many of our adult organs possess a tiny population of stem cells that are capable of immortal regeneration. Stem cells are the body’s reservoir of renewal. The entirety of human blood, for instance, can arise from a single, highly potent blood-forming stem cell that typically lives buried inside the bone marrow." And many cancers arise from stem cells. https://lnkd.in/eNxs3pb View in LinkedIn

REFLECTED LIGHT CUES. "In some food deceptive orchids, similarities in the spectral reflectance visible to the pollinator in a model plant and its mimic, and increased reproductive success of the mimic in the presence of the model have been demonstrated." https://lnkd.in/dQxZZsA View in LinkedIn

NORMAL LIFESPAN. “We suggested that the finite capacity of normal cells to replicate was a reflection of ageing or longevity determination at the cell level, an idea that received substantial support in subsequent years.” https://lnkd.in/esfPTAR View in LinkedIn

MORTAL NORMAL CELLS. “By mid century the immortality of cancer cells was demonstrated in vitro, followed by the finding that, contrary to prevailing belief, cultured normal cells are mortal.” https://lnkd.in/esfPTAR View in LinkedIn

HOUSEHOLD NAME. “Leonard Hayflick (born 20 May 1928 in Philadelphia, Pennsylvania), Ph.D., is an American anatomist. He is the Professor of Anatomy at the University of California, San Francisco, School of Medicine, and was Professor of Medical Microbiology at Stanford University School of Medicine. He is a past president of the Gerontological Society of America and was a founding member of the council of the National Institute on Aging (NIA).” https://en.m.wikipedia.org/wiki/Leonard_Hayflick View in LinkedIn

LEONARD HAYFLICK "and his associates have vehemently condemned "anti-aging medicine" and criticized organizations such as the American Academy of Anti-Aging Medicine. Hayflick has written numerous articles criticizing both the feasibility and desirability of human life extension, which have provoked responses critical of his views.” https://lnkd.in/egWqSRn View in LinkedIn

THE HAYFLICK LIMIT. "Dr. Hayflick noticed that cells grown in cultures reproduce by dividing. They produce facsimiles of themselves (by a process known as mitosis) a finite number of times before the process stops for good and the cell dies. In addition, cells frozen during their lifetimes and later returned to an active state had a kind of cellular memory: The frozen cells picked up right where they left off. In other words, interrupting the cells' life span did nothing to lengthen it.” https://lnkd.in/eXXDjuG View in LinkedIn

PROFESSOR LEONARD HAYFLICK has probably done more for the biology of aging than anybody else. Excerpts from some of his papers will be quoted extensively in the coming sections. He is a contrarian with strong views. http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

TELOMERE HYPOTHESIS. "A current hypothesis gaining prominence proposes that activation of the enzyme telomerase is necessary for cells to become immortal, or capable of proliferating indefinitely. The theory suggests that almost all cancer cells must attain immortality for progression to malignant states and, hence, require activation of telomerase.” https://lnkd.in/efS2ct4 View in LinkedIn