User:Hmc442/Vacuum Activity

= Vacuum Activity = Vacuum activities (or vacuum behaviours) are innate, fixed action patterns (FAPs) that are produced in the absence of a sign stimulus (or releaser) that normally elicits them. These types of behaviours normally take place when an animal is placed in captivity and/or no longer perceives a particular stimulus, so it carries out the corresponding behaviour unprompted.

Lorenz's Hydraulic Model of Motivation
Animals that were raised without releasing instinctual behaviours, due to being in captivity or being taken as a pet, will produce these vacuum behaviours in seemingly random moments due to a build-up of energy reserves. This theory is based on Lorenz's Hydraulic Model of Motivation, which attempts to explain the mechanism of FAPs by equating energy input to water adding up in a container, leading to a valve which, under normal circumstances, is opened upon addition of a releaser or sign stimulus, to produce a FAP. When a sign stimulus or releaser is not present, this leads to an energy (water) build-up, forcing the valve open and producing the fixed action pattern in the absence of the correct stimulus.

Evolution and Genetics
Over time as animals have evolved, natural selection has favoured some behaviours over others because they have ensured the survival and reproduction of the animal. These potentially long-lasting, innate behaviours have a genetic origin that propagates through evolutionary time, becoming slightly altered due to environmental changes and mutations. The study of Epigenetics explains how certain mutations (e.g., histone modification and DNA methylation) affect how genes are expressed without altering the genetic code, suggesting learning from the environment can change gene expression, and thus neural pathways, to modify the animals behaviour within its lifetime. These FAPs, or instinctual, stereotyped behaviours lead to the production of vacuum activities when the environment is lacking the necessary stimuli, revealing a deeply intwined relationship between an external stimulus in the environment, genes, and learning. This is illustrated in the act of primates shaking branches in their natural environment to cause a distraction from predators and the inclination for captive primates in zoos to shake roof beams even though they cannot know if a predator is outside. The animals physiology is attempting to produce an instinctual behaviour that is common for that particular species but the necessary external stimulus is not present.