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Biological Systems

0400: Feedback loops

Niall Palfreyman
This is a collection of models which illustrate the idea of feedback loops, which form the basis of all living systems.

1. The first is an open-loop model - that is, it contains no feedback. The process of gravitational acceleration g changes the speed of a falling ball, but this speed has no feedback effect on gravity.

2. The second model contains a positive feedback loop. A greater number of Bacteria causes the number of cell divisions to increase, and the process of cell division itself also increases the number of Bacteria. The process 'division' and the state variable 'Bacteria' both have a positive effect on each other, generating unconstrained growth.

3. The third model contains a negative feedback loop. A greater number of TumourCells causes the number of cell deaths to increase, but the process of cell death itself decreases the number of TumourCells. The process 'death' negatively influences the state variable 'TumourCells', while 'TumourCells' positively influences 'death', causing the TumourCells to decay to zero.

HSWT BPI Biological Systems

  • 2 years 6 months ago

Daisyworld

France Caron
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.
Based on 0409-DaisyworldInsight Original Author: Niall Palfreyman

HSWT BPI Biological Systems

  • 8 months 1 day ago

Daisyworld modificado - mamenac

María Alejandra Mena Castro
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.

HSWT BPI Biological Systems

  • 1 year 1 month ago

Clone of Clone of 0409: Daisyworld

Tobias Meier
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.

HSWT BPI Biological Systems

  • 2 years 5 months ago

Clone of 0409: Daisyworld

Adrian Marcus
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.

HSWT BPI Biological Systems

  • 2 years 7 months ago

Clone of 0409: Daisyworld

Tobias Meier
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.

HSWT BPI Biological Systems

  • 2 years 7 months ago

Clone of Clone of 0409: Daisyworld

Alexander
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.

HSWT BPI Biological Systems

  • 2 years 7 months ago

Clone of 0409: Daisyworld

Anna Blümel
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.

HSWT BPI Biological Systems

  • 2 years 6 months ago

Clone of Clone of The Best Daisyworld 3.0

HelloWorld
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.

HSWT BPI Biological Systems

  • 1 year 8 months ago

Clone of Clone of Clone of 0409: Daisyworld

Anna Blümel
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.

HSWT BPI Biological Systems

  • 2 years 6 months ago

Clone of 0409: Daisyworld

Heinzel
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.

HSWT BPI Biological Systems

  • 2 years 7 months ago

Clone of Clone of 0409: Daisyworld

Heinzel
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.

HSWT BPI Biological Systems

  • 2 years 6 months ago

Clone of Influence of Sympatric Speciation on Regulation

RS Brückl
We extended Daisyworld to evaluate the effects of sympatric speciation on regulation. Sympatric speciation occurs when organisms are segregated from each other by functional, rather than spatial, constraints. The dynamical model contains five potential species: gray, light gray, dark gray, black and white daisies, whose phenotypes differ only in their albedo.

Initially the model contains only gray daisies. Mutation of gray daisies leads to new daisy types. These new types can interbreed with their genetic neighbors or mutate even further. These mutations ultimately lead to black or white daisies.  When two types are functionally different enough they cannot interbreed and we consider them separate species.

Instructions:

You can change the 'Spread' of albedo between the different daisy types centered at the albedo of the gray daisies and in symmetric shades.

'gamma' is the general death rate for all daisies.

The 'Flow' defines the percentage of the actual population which mutates.

'q' defines the spatial distribution of thermal energy between the dasies.

'Base' is the optimal temperature of the general daisy.

'mu' is the probability of a mutation event.

Our model contains two possible luminosity scenarios. One relates to the increasing luminosity of the original Daisyworld. There is a second scenario implemented, which simulates different pertubations over a normally constant luminosity. To change between the scenarios simply reconnect the 'Absorbed Luminosity' variable with one of the container 'L'. Both scenarios are depicted in the diagram, so no changes are neccessary.

HSWT BPI Biological Systems

  • 2 years 5 months ago

Clone of 0409: Daisyworld

RS Brückl
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.

HSWT BPI Biological Systems

  • 2 years 7 months ago

Clone of 0409: Daisyworld

Heinzel
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.

HSWT BPI Biological Systems

  • 2 years 6 months ago

Clone of 0409: Daisyworld

RS Brückl
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.

HSWT BPI Biological Systems

  • 2 years 7 months ago

Clone of 0409: Daisyworld

Jan Naahs
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.

HSWT BPI Biological Systems

  • 2 years 7 months ago

Clone of 0409: Daisyworld

Hoepfl
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.

HSWT BPI Biological Systems

  • 2 years 5 months ago

Clone of Clone of 0409: Daisyworld

Cuong Quang
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.

HSWT BPI Biological Systems

  • 2 years 6 months ago

Clone of 0409: Daisyworld

Leidy Muñoz Garcia
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.

HSWT BPI Biological Systems

  • 1 year 1 month ago

Clone of 0409: Daisyworld

Tobias Meier
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.

HSWT BPI Biological Systems

  • 2 years 6 months ago

Clone of 0409: Daisyworld

María José Andrade Tafur
Darwinian Daisyworld model from and Watson & Lovelock (1983), Robertson & Robinson (1998) and Lenton & Lovelock (2001).

Units of time are 40 Myr, giving R&R's span of 10 Gyr.

This model offers many opportunities for modification. Maybe the Black and White populations can mutate into each other? The role of q as a measure of segregation of the B and W populations is interesting, and while this model uses purely stigmergic communication between species, direct interaction would also be possible.

HSWT BPI Biological Systems

  • 1 year 1 month ago

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