Hi. What is the kind of question you would like to answer using SPLATCHE3 ? Do you want to simulate only demography or also genetics ? How much do you know about your biological model ? Those are some of the questions you want to ask yourself before going into more technical issues.

You can find file examples on the splatche3 dedicated website, as well as a very detailed manual. However, i know by experience that because there is a lot of information to provide to numerous files, it can be tricky to use.

I would first suggest you to try one of the examples from the website to be sure it runs well on your machine/server (try both the graphical and the bash versions). As a second point i would suggest you to modify some of the parameters to see how each one can affect the demography of your population(s). For example, change the location of the population from the "dens_init" file, the numbers of the "veg2K" files, add lines to the "dynamic2K" and the first line should fit the number of lines. Those are some examples that could help you to better understand how splatche works. Once you are more familiar with the parameters, you will want to adapt those to your data and your research question. The map on which your population will evolve has to fit your biological model: each deme is supposed to represent a sub-population that exchange genes as in panmixia. But, each deme will exchange genes with neighbouring demes through the migration rate at each generation. This means your simulation would not be helpful if you want it to represent how your population evolve during less than a generation, unless you are only interested in demography.

Lets suppose you want to answer a question that involves the evolution of your population and genes during tens, hundreds or even thousands of generations, then you would like to know which kind of genetic data you would like to simulate : read the manual to know more about the format of each kind of genetic data because each has its own and we do not want to read here what is already well written in the manual.

SPLATCHE3 supports the simulation of two layers of populations that can interact by exchanging genes at a certain rate. It is also possible to make a proportion of each sub-subpopulation migrate at long distance instead of neighbouring demes only : check the ability of your biological model to see if it fits or not. Finally, if you simulate two layers of populations, are they in competition ? What kind of competition ? If you arrive at this stage, and you have another question, let me know.