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GIANT LIFESPANS AND EVEN IMMORTALITY are demonstrated by numerous examples from the natural world. This rather stunning, and generally unappreciated fact that lifespans are not all programmed to be short raises many interesting possibilities. I will highlight some interesting examples from nature in the following postings. View in LinkedIn

Radical Kenya's plastic bag ban: minor teething problems to be solved by cheap biodegradables. View in LinkedIn

Party leaders urge Theresa May to act on childhood obesity https://www.theguardian.com/society/2018/apr/25/party-leaders-urge-theresa-may-to-act-on-childhood-obesity?CMP=Share_iOSApp_Other View in LinkedIn

THE AND ENERGY COST. "Finding mates requires time and energy. Finally, recombination may break down existing genetic associations generated by natural selection, leading to “recombination load.” http://onlinelibrary.wiley.com/doi/10.1002/ece3.1516/full View in LinkedIn

CONTRARIAN VIEW. "Human life histories, as compared to those of other primates and mammals, have at least four distinctive characteristics: an exceptionally long lifespan, an extended period of juvenile dependence, support of reproduction by older post-reproductive individuals, and male support of reproduction through the provisioning of females and their offspring." A fascinating read. https://lnkd.in/dDxfUbh View in LinkedIn

NUTRIENT COMPETITION. "To grow faster, plants must allocate more resources, primarily nitrogen, to photosynthesis. Nitrogen is one of the most important limiting resources for plant growth in nature, and most leaf nitrogen is allocated to photosynthesis. Small changes in nitrogen allocation can greatly influence light-saturated photosynthetic rate (Pmax) and photosynthetic nitrogen-use efficiency (PNUE), and therefore plant performance. Leaf nitrogen that is not allocated to photosynthesis is generally used structurally in cell walls, a component of plant defense and chemical defenses." https://lnkd.in/dM3QBWR View in LinkedIn

SINKS TRUMP SOURCES. "A semelparous plant dies because its sink tissues kill its source organs by a kind of starvation, by induction of senescence in response to nutrient diversion or by export of a ‘death hormone'." (Semelparous organisms have only one reproductive episode before death). https://lnkd.in/dPac2Jv View in LinkedIn

NUTRIENT SOURCES. "Organs that supply the precursors for sink metabolism are sources. Sources and sinks communicate through the vascular system. During development of the endosperm of cereal grains and the parenchyma of potato tubers, large amounts of starch are accumulated. These organs are supplied via the phloem with assimilated C mostly fixed by current photosynthesis." (C = carbon), https://lnkd.in/dPac2Jv View in LinkedIn

NUTRIENT SINKS. "A sink is defined as a net importer of nutrients (nitrogen (N), phosphorus (P), potassium (K), sulfur (S) and other minerals) and assimilates carbon (C) derived directly or indirectly from photosynthesis. Developing seeds, bulbs, tubers and other structures that accumulate storage compounds are strong sinks, as are expanding leaves and branches during vigorous vegetative growth." https://lnkd.in/dPac2Jv View in LinkedIn

NUTRIENT ALLOCATION. "I see hardly any way of distinguishing between the effects, on the one hand, of a part being largely developed through natural selection and another and adjoining part being reduced by this same process. . .and, on the other hand, the actual withdrawal of nutriment from one part owing to the excess of growth in another and adjoining part." (Darwin). https://lnkd.in/d6g52rz View in LinkedIn