April 9, 2003 - The mat-ministromatolite bioherms from the Proterozoic Wumishan Formation exhibit three orders of cyclic growth patterns. The growth cycle can be interpreted in terms of daily, monthly and seasonal periodicities. Mat-ministromatolite bioherms used as palaeontological clocks are limited to a short (daily and monthly) growth cycle.

The attainment of a critical size triggers the periodic events of the cycle such as the S period and mitosis. This control acts as a homeostatic effector that maintains a constant "average" cell size at division through successive cycles in a growing culture. It is a vital link coordinating cell growth with periodic events of the cycle.

However, with a sufficient source of energy, once established the cycle would begin to grow; as a result, those processes that are part of the cycle will gradually come to dominate their environment.6 At the same time, informational entropy production associated with growth will substantially increase the complexity (indeterminate information capacity) of the system, potentiating the emergence of new processes that increase the system's development capacity and degrees of freedom (Figure 1).

March 17, 2025 - This graph shows the 10-year cyclical fluctuations in the populations (measured by counting the hides offered for sale at the Hudson Bay trading posts in Canada) of the varying hare ("snowshoe rabbit") and its chief predator, the lynx, from 1850 to 1910. The size of the lynx population was closely dependent on the size of its prey (hare) population.

September 15, 2021 - Summary: Dermal components of feather follicles undergo large scale remodeling involving stem cells, transient amplifying cells and differentiated cells. The control of this homeostasis in physiological and plucked-induced cycling is analyzed.

Reed H. S. The Dynamics of a Fluctuating Growth Rate. Proc Natl Acad Sci U S A. 1920 Jul;6(7):397–410. doi: 10.1073/pnas.6.7.397.

Growth induction in resting fibroblast cultures by serum or growth factors induces a fast, transient cGMP peak which may constitute the intracellular signal for growth. A similar cGMP peak occurs when 3T3 cells arrested at the restriction point ...

To characterize cyclic dynamics, long-term data can be subjected to autocorrelation analysis and continuous wavelet analysis. The autocorrelation function, or ACF, is estimated by calculating the correlation between pairs of log-transformed population densities and the autocoefficients are then plotted against lag intervals, usually generations or years (Berryman and Turchin, 2001). Berryman and Turchin recommend that for biological ...

January 1, 1978 - Edward M. Johnson, Growth and Cyclic Nucleotides, BioScience, Volume 28, Issue 1, January 1978, Page 50, https://doi.org/10.2307/1307490

January 26, 2026 - In other words, species life history ... cyclically under the influence of surrounding species. These periodic shifts in life history properties produce observable changes in community composition. In the system Watt observed, phasic development was specifically responsible for changes in growth and mortality ...

Nature - Growth Patterns in Neurospora: Genetic Control of a Cyclic Growth Pattern in Neurospora

March 21, 2018 - Population cycles are one of nature's great mysteries. For almost a hundred years, innumerable studies have probed the causes of cyclic dynamics in snowshoe hares, voles and lemmings, forest Lepidoptera and grouse. Even though cyclic species have ...

April 13, 2026 - The most well known example of creatures which have a population cycle is the lemming. The biologist Charles Sutherland Elton first identified in 1924 that the lemming had regular cycles of population growth and decline.

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March 1, 2018 - Thus much basic population ecology has been done with cyclic species. The dynamics of lynx, Lynx canadensis, and snowshoe hares, Lepus americanus [1] (figure 1), was the first empirical demonstration of the predator–prey cycles described in the classic models that Lotka and Volterra developed during the 1920s. In 1931, the Matamek Conference on Biological Cycles considered the potential roles of predators, parasites and food on population cycles, as well as extrinsic factors such as temperature, rain and sunspot cycles [2].

Welcome to the fascinating subject of ecology! From population dynamics to biodiversity, this unit explores the complex web of interactions that make up our natural world.

June 1, 2000 - Here we show that a reduction in the length of the cell-cycle G1 phase and faster cell cycling occur when the rate of cell division in transgenic tobacco plants is increased by the plant D-type cyclin CycD2 (ref. 8). The plants have normal cell and meristem sizes, but elevated overall growth rates, an increased rate of leaf initiation and accelerated development in all stages from seedling to maturity.

April 16, 2018 - In this paper, we explore the potential for density-dependent, cyclic population dynamics and intransitivity in a model for annual plants. We then examine how these density-dependent cycles impact mutual invasibility and ultimately stable coexistence between plant species pairs. We do this using data collected from four co-occurring annual plant species living in natural wildflower communities in SW Western Australia. To maximise the number of biologically plausible pathways by which coexistence mediated by density-dependent cyclic intransitivity can occur, we use an annual plant model that allows for competitive direct interactions, facilitative direct interactions and higher-order interactions between species.

The addition of serum to nongrowing cells decreases cyclic guanosine monophosphate and cyclic adenosine monophosphate levels and promotes cell growth.

NON-TRANSFORMED fibroblastic cells in tissue culture exist in one of two reversible growth states, a state of rapid proliferation (growing) and a state of relative quiescence (resting)1,2. Transition from a resting to a growing state can be accomplished by a variety of mitogenic agents including growth substances in animal sera, insulin and proteases. 3′, 5′-cyclic adenosine monophosphate (cyclic AMP) was implicated in this transition3,4 in that the intracellular concentrations of cyclic AMP in resting cell cultures fall after brief exposure to mitogenic agents3,4 and exogenous additions of high concentrations (10−4 to 10−3M) of dibutyryl cyclic AMP to the culture medium cause a partial reversal of the mitogenic response5.