Obtain construction materials Manufacture new parts including its smallest parts and thinking apparatus Provide a consistent power source Program the new members error correct any mistakes in the offspring On a nano scale, assemblers might also be designed to self-replicate under their own power. This, in turn, has given rise to the "grey goo" version of Armageddon, as featured in the science fiction novels Bloom and Prey. The Foresight Institute has published guidelines for researchers in mechanical self-replication. The guidelines recommend that researchers use several specific techniques for preventing mechanical replicators from getting out of control, such as using a broadcast architecture. For a detailed article on mechanical reproduction as it relates to the industrial age see mass production. Fields Research has occurred in the following areas: Biology: studies of organismal and cellular natural replication and replicators, and their interaction, including sub-disciplines such as population dynamics, quorum sensing, autophagy pathways. These can be an important guide to avoid design difficulties in self-replicating machinery. Chemistry: self-replication studies are typically about how a specific set of molecules can act together to replicate each other within the set (often part of Systems chemistry field). Biochemistry: simple systems of in vitro ribosomal self replication have been attempted, but as of January 2021, indefinite in vitro ribosomal self replication has not been achieved in the lab. Nanotechnology or more precisely, molecular nanotechnology is concerned with making nano scale assemblers. Without self-replication, capital and assembly costs of molecular machines become impossibly large. Many bottom-up approaches to nanotechnology take advantage of biochemical or chemical self-assembly. Space resources: NASA has sponsored a number of design studies to develop self-replicating mechanisms to mine space resources. Most of these designs include computer-controlled machinery that copies itself. Memetics: The idea of a meme was coined by Richard Dawkins in his 1976 book The Selfish Gene where he proposed a cognitive equivalent of the gene; a unit of behavior which is copied from one host mind to another through observation. Memes can only propagate via animal behavior and are thus analogous to information viruses and are often described as viral. Computer security: Many computer security problems are caused by self-reproducing computer programs that infect computers — computer worms and computer viruses. Parallel computing: loading a new program on every node of a large computer cluster or distributed computing system is time consuming. Using a mobile agents to self-replicate code from node-to-node can