Reproduction settings

These settings control how creatures are born and die in Avida.

BIRTH_METHOD	The birth method sets how the placement of a child organism is determined. Currently, there are six ways of doing this -- the first four (0-3) are all grid-based (offspring are only placed in the immediate neighborhood), and the last two (4-5) assume a well-stirred population. In all non-random methods, empty sites are preferred over replacing a living organism. See the avida.cfg file itself for details.
DEATH_METHOD AGE_LIMIT	By default, replacement is the only way for an organism to die in Avida. However, if a death method is set, organisms will die of old age. In method one, organisms will die when they reach the user-specified age limit. In method 2, the age limit is a multiple of their length, so larger organisms can live longer.
ALLOC_METHOD	During the replication process in the default virtual CPU, parent organisms must allocate memory space for their child-to-be. Before the child is copied into this new memory, it must have an initial value. Setting the alloc method to zero sets this memory to a default instruction (typical nop-A). Mode 1 leaves it uninitialized (and hence keeps the contents of the last organism that inhabited that space; if only a partial copy occurs, the child is a hybrid if the parent and the dead organism, hence the name necrophilia). Mode 2 just randomizes each instruction. This means that the organism will behave unpredictably if the uninitialized code is executed.
DIVIDE_METHOD	When a divide occurs, does the parent divide into two children, or else do we have a distinct parent and child? The latter method will allow more age structure in a population where an organism may behave differently when it produces its second or later offspring.
GENERATION_INC_METHOD	The generation of an organism is the number of organisms in the chain between it and the original ancestor. Thus, the generation of a population can be calculated as the average generation of the individual organisms. When a divide occurs, the child always receives a generation one higher than the parent, but what should happen to the generation of the parent itself? In general, this should be set the same as divide method.

See the avida.cfg file for further settings: DIVIDE_FAILURE_RESETS, PREFER_EMPTY, ALLOW_PARENT, DISPERSAL_RATE, DEATH_PROB, AGE_LIMIT, AGE_DEVIATION, EPIGENETIC_METHOD, RESET_INPUTS_ON_DIVIDE, INHERIT_MERIT, and INHERIT_MULTITHREAD.