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EU member states to vote on near-total neonicotinoids ban http://www.bbc.co.uk/news/science-environment-43910536 View in LinkedIn

SELECTION OF THE FITTEST. "We argue that competition between genetically identical cells could improve the fitness of a multicellular organism by directing fitter cells to the germ line or by eliminating unfit cells, and that cell-competition mechanisms have been conserved in multicellular organisms. We propose that competition between genetically identical or highly similar units could have similar selective advantages at higher organizational levels, such as societies." https://lnkd.in/dXdwAzF 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

SYMBIOTIC COMPETITION. “Similar kinds of reproductive competition are predicted to occur in some other symbiotic relationships, and possible examples are presented for two of them: bacterial plasmids and endozoic algae." http://www.jstor.org/stable/2824738?seq=1#page_scan_tab_contents View in LinkedIn

COMPETITION WITHIN. "I propose that in certain circumstances natural selection favors intraorganismal reproductive competition between different varieties of organelle DNA, and in other circumstances selection favors competition between organelle and nuclear DNA. Evidence is marshalled to show that such competition occurs in nature. Situations which would lead to selection for both kinds of competition are described and are shown to be relatively common." (1980). http://www.jstor.org/stable/2824738?seq=1#page_scan_tab_contents View in LinkedIn

CELLULAR ECOSYSTEM. "A eukaryotic cell can be likened to a society composed of a nucleus and a crowd of subcellular organelles in which all members cooperate for the common good." https://lnkd.in/dSKRVqw View in LinkedIn