The composition of organic matter and fluctuations of thermodynamic parameters were investigated in the hydrothermal systems of the Kamchatka peninsula in the context of the origin of life. Organics were analyzed by gas-chromatography/mass spectrometry, and 111 organic compounds belonging to 14 homologous series (aromatic hydrocarbons, alkanes and isoalkanes, halogenated aromatic hydrocarbons, carboxylic acids, esters, etc.) were found in hot springs inhabited by Archaeal and Bacterial thermophiles. The organics detected in the sterile condensate of water-steam mixture taken from deep boreholes (temperature 108-175 °C) consisted of 69 compounds of 11 homologous series, with aromatic hydrocarbons and alkanes being prevalent. The organic material included important prebiotic components such as nitrogen-containing compounds and lipid precursors. A separate organic phase (oil) was discovered in the Uzon Caldera. A biogenic origin is supported by the presence of sterane and hopane biomarkers and the δ(13)C value of the bulk oil; its age determined by (14)C measurements was 1030 ± 40 years. Multilevel fluctuations of thermodynamic parameters proposed to be required for the origin of life were determined in the Mutnovsky and Pauzhetsky hydrothermal systems. The low-frequency component of the hydrothermal fluid pressure varied by up to 2 bars over periods of hours to days, while mid-frequency variations had regular micro-oscillations with periods of about 20 min; the high-frequency component displayed sharp changes of pressure and microfluctuations with periods less than 5 min. The correlation coefficient between pressure and temperature ranges from 0.89 to 0.99 (average 0.96). The natural regimes of pressure and temperature fluctuations in Kamchatka hydrothermal systems can guide future experiments on prebiotic chemistry under oscillating conditions.
The paper investigates the phase multistability of dynamical modes of the Ricker model with 2-year periodic Malthusian parameter. It is shown that both the variable perturbation
and the phase shift of the Malthusian parameter can lead to a phase shift or a change in the dynamic mode observed. The possibility of switches between different dynamic modes
is due to multistability, since the model has two different stable 2-cycles. The first stable 2-cycle is the result of transcritical bifurcation and is synchronous to the oscillations
of the Malthusian parameter. The second stable 2-cycle arises as a result of the tangent bifurcation and is asynchronous to the oscillations of the Malthusian parameter.
This indicates that two-year fluctuations in the population size can be both synchronous and asynchronous to the fluctuations in the environment. The phase shift of the Malthusian parameter
causes a phase shift in the stable 4-cycle of the first bifurcation series to one or even three elements of the 4-cycle. The phase shift to two elements of this 4-cycle is possible due
to a change in the half-amplitude of the Malthusian parameter oscillation or the variable perturbation. At the same time, the longer period of the cycle, the more phases with
their attraction basins it has, and the smaller the threshold values above which shift from the attraction basin to another one occur. As a result, in the case of cycles
with long period (for example, 8-cycle) perturbations, that stable cycles with short period are able to "absorb", can cause different phase transitions, which significantly complicates
the dynamics of the model trajectory and, as a consequence, the identification of the dynamic mode observed.
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