A series of dates of unfolding of the first leaves and duration of the season of vegetation in the silverbirch (Betula pendula Roth. (B. verrucosa Ehrh.)), as well as the duration of flowering of the bird cherry (PaFdus avium), mountain ash (Sorbus aucuparia), andsmall-leaved lime (Tilia cordata Mill.) for the period1970–2010 in the central part of European Russia were studied in order to assess the trends. Differences in phenological responses to homogeneous climate changes in the trees of the same species from the northernand southern parts of the range were revealed. If spring events occur 3–7 days earlierin the northern part, nosuch effect is observed in the south. This fact can be interpreted as a manifestation of the different mechanisms of homeostasis in different populations determined by their biological characteristics (in particular, by the need to pass successfully the periods of organic rest and vegetation).
The study of the indices of developmental homeostasis in natural populations leads to the definition of the fundamentals of population developmental biology, which is associated with the assessment of the nature of phenotypic diversity and the mechanisms of population dynamics and microevolutionary changes. Characterization of environmental quality based on the assessment of population status by developmental homeostasis determines the fundamentals of the health of environment concept. The use of the ideas of developmental homeostasis and the health of environment in the studies of homeostatic mechanisms of biological systems of different levels (from the organism and population to the community and ecosystem) is promising. This gives new opportunities for understanding the mechanisms that provide sustainability and their ratio at different levels as well as for the characterization of ontogenetic stability significance. The notion of developmental homeostasis, or homeorhesis, is promising for the elaboration of the ecological and biological basics of sustainable development.
In the majority of angiosperms, the floral organs are initiated acropetally – the first organs to be initiated are the perianth members and the last organs are the carpels. The relatively rare examples of non-acropetal patterns of organ initiation can be found in oligomerous as well as in polymerous flowers. Taxa sharing the same non-acropetal developmental patterns are not necessarily closely related to each other and thus similarities in their floral structure and development should be regarded as convergences. And vice versa, representatives of the same family often show different patterns of initiation of floral organs. Flowers with the same groundplan can demonstrate either typical acropetal or non-acropetal developmental pattern. In other words, the floral developmental patterns are rather homoplastic. Non-acropetal patterns (and reversals to the acropetal condition) appeared many times in angiosperm evolution. Such labile and apparently saltational transitions are probably due to special features of floral meristems and modular organisation of angiosperm flowers.