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The article presents the discussion on parenting babies and small children having many similarities. Topics include sharing a proclivity to sap energy, disrupting sleep, dysregulating circadian rhythms involving noisy, often tearful chaos and getting covered in others' bodily fluids; and accessing to regular breaks as well as a private area in expressing and safely storing breastmilk.

Abstract Remnants of native riparian vegetation on the floodplain of the Hawkesbury–Nepean River near Sydney, have significant conservation value, but contain a large component of weeds (i.e. exotic species that have become naturalized). A proposal for the introduction of environmental flows required an assessment of potential impacts on 242 native and 128 exotic species recorded along 215 km of the river. The likely effects of frequency, season, depth and duration of inundation were considered in relation to habitat, dispersal season and tolerance to waterlogging. Overseas studies provided only limited information applicable to the study area; however, comparisons with similarly highly modified riparian habitats in New Zealand were instructive. Depth and season of inundation appear to be the variables with the greatest potential for differential effects on weeds and native plants. Because of likely spread of propagules and enhancement of growth under the present nutrient-enriched conditions, environmental flows that would cause more frequent flooding to higher levels of the riparian zone were judged to be of more benefit to weed species than native species, unless supported by bushland management including weeding. Predictions were limited by incomplete data on Hawkesbury–Nepean species, but two types of environmental flow were judged to be potentially beneficial for native water-edge plants, and worth testing and monitoring: first, flows that maintain continuous low-level flow in the river, and second, higher level environmental flows restricted to the river-edge habitat in autumn (the season in which a greater proportion of native species than weed species are known to disperse propagules). In summary, the presence of environmental weeds in riparian vegetation constrain the potential for environmental flows to improve river health. However, with ongoing monitoring, careful choice of water level and season of flow may lead to environmental flows... [ABSTRACT FROM AUTHOR]

(1) The self-thinning rule describes an outer boundary on the trajectories which even-aged stands of plants can follow in a space of log biomass υ log density. An important variant to the rule occurs in dense shade, but the exact nature of the variant remains unclear. We describe three alternative models of the effect of dense shade on the rule. (2) To test these models, we grew some stands of Trifolium subterraneum in a glasshouse m full daylight and others shaded at 30% of full daylight after a period, some full-light stands were moved to the shade, and some shaded stands to full daylight (3) The results showed that the slope of the trajectory of a stand growing in shade is determined not only by the light climate but also by its position with respect to the relevant thinning line. This observation excludes one of the three models We discuss the evidence bearing on the correctness of the other two models. [ABSTRACT FROM AUTHOR]

(1) The self thinning rule describes the mortality of plants undergoing competitive thinning in a crowded even-aged stand as a function of accumulation of biomass or weight without reference to the passage of time. It has been thought that an important exception to the rule occurs at low light flux, with the slope of the thinning line changing from -½ (biomass basis) to 0. (2) Silverbeet populations were grown m a glasshouse in full light and under various shade treatments Some plants were grown during summer and others during winter. (3) Full daylight in winter was about 55% of that in summer. The winter treatments self throned as if they were summer treatments subjected to that amount of extra shade. (4) The effect of shading down to 18% of summer daylight was progressively to decrease the intercept of the throning line on the biomass axis, without changing its slope. At 9% of summer daylight mortality was high while biomass decreased, i.e. the slope was positive, presumably this light flux was below the compensation point. The results suggested that a zero slope could only be obtained as a transitional phenomenon, at a light flux immediately above the compensation point. (5) The difference between full-daylight treatments in summer and in winter suggests that some of the reported variation between stands in the level of the thinning line may be a function of the different light climates in which the stands were grown. [ABSTRACT FROM AUTHOR]