Avida is an

artificial life Artificial life (often abbreviated ALife or A-Life) is a field of study wherein researchers examine systems related to natural life, its processes, and its evolution, through the use of simulations with computer models, robotics, and biochemistry ...

software platform to study the

evolutionary biology Evolutionary biology is the subfield of biology that studies the evolutionary processes (natural selection, common descent, speciation) that produced the diversity of life on Earth. It is also defined as the study of the history of life fo ...

self-replicating Self-replication is any behavior of a dynamical system that yields construction of an identical or similar copy of itself. Biological cells, given suitable environments, reproduce by cell division. During cell division, DNA is replicated and ca ...

and

evolving Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation t ...

computer program A computer program is a sequence or set of instructions in a programming language for a computer to execute. Computer programs are one component of software, which also includes documentation and other intangible components. A computer program ...

s (

digital organism A digital organism is a self-replicating computer program that mutates and evolves. Digital organisms are used as a tool to study the dynamics of Darwinian evolution, and to test or verify specific hypotheses or mathematical models of evolut ...

s). Avida is under active development by

Charles Ofria Dr. Charles A. Ofria is a Professor in the Department of Computer Science and Engineering at Michigan State University, the director of the Digital Evolution (DEvo) Lab there, and Director of the BEACON Center for the Study of Evolution in Actio ...

's Digital Evolution Lab at

Michigan State University Michigan State University (Michigan State, MSU) is a public university, public Land-grant university, land-grant research university in East Lansing, Michigan. It was founded in 1855 as the Agricultural College of the State of Michigan, the fi ...

; the first version of Avida was designed in 1993 by Ofria,

Chris Adami Christoph Carl Herbert "Chris" Adami (born August 30, 1962) is a professor of Microbiology and Molecular Genetics, as well as professor of Physics and Astronomy, at Michigan State University. Education Adami was born in Brussels, Belgium, and gra ...

and C. Titus Brown at

Caltech The California Institute of Technology (branded as Caltech or CIT)The university itself only spells its short form as "Caltech"; the institution considers other spellings such a"Cal Tech" and "CalTech" incorrect. The institute is also occasional ...

, and has been fully reengineered by Ofria on multiple occasions since then. The software was originally inspired by the

Tierra Tierra may refer to: Astronomy *Earth in the Spanish and Asturian language Computing and games * Tierra (computer simulation), a computer simulation of life by the ecologist Thomas S. Ray * Tierra Entertainment, now known as AGD Interactive, a ...

system.

Design principles

simulated an evolutionary system by introducing computer programs that competed for computer resources, specifically processor (CPU) time and access to main memory. In this respect it was similar to Core Wars, but differed in that the programs being run in the simulation were able to modify themselves, and thereby evolve. Tierra's programs were artificial life organisms. Unlike Tierra, Avida assigns every digital organism its own protected region of memory, and executes it with a separate virtual

CPU A central processing unit (CPU), also called a central processor, main processor or just processor, is the electronic circuitry that executes instructions comprising a computer program. The CPU performs basic arithmetic, logic, controlling, and ...

. By default, other digital organisms cannot access this memory space, neither for reading nor for writing, and cannot execute code that is not in their own memory space. A second major difference is that the virtual CPUs of different organisms can run at different speeds, such that one organism executes, for example, twice as many instructions in the same time interval as another organism. The speed at which a virtual CPU runs is determined by a number of factors, but most importantly, by the ''tasks'' that the organism performs: logical computations that the organisms can carry out to reap extra CPU speed as bonus.

Use in research

Adami and Ofria, in collaboration with others, have used Avida to conduct research in digital evolution, and the scientific journals ''

Nature Nature, in the broadest sense, is the physics, physical world or universe. "Nature" can refer to the phenomenon, phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. ...

'' and ''

Science Science is a systematic endeavor that builds and organizes knowledge in the form of testable explanations and predictions about the universe. Science may be as old as the human species, and some of the earliest archeological evidence for ...

'' have published four of their papers. The 2003 paper "The Evolutionary Origin of Complex Features" describes the evolution of a mathematical

equal Equal(s) may refer to: Mathematics * Equality (mathematics). * Equals sign (=), a mathematical symbol used to indicate equality. Arts and entertainment * ''Equals'' (film), a 2015 American science fiction film * ''Equals'' (game), a board game ...

operation Operation or Operations may refer to: Arts, entertainment and media * ''Operation'' (game), a battery-operated board game that challenges dexterity * Operation (music), a term used in musical set theory * ''Operations'' (magazine), Multi-Ma ...

from simpler bitwise operations.

Use in education

The Avida-ED project
Avida-ED
uses the Avida software platform within a simplified graphical user interface suitable for use in evolution education instruction at the high school and undergraduate college level, and provides freely available software, documentation, tutorials
lesson plans
and other course materials. The Avida-ED software runs as a web application in the browser, with the user interface implemented in JavaScript and Avida compiled to JavaScript using Emscripten, making the software broadly compatible with devices commonly used in classrooms. This approach has been shown to be effective in improving students' understanding of evolution. The Avida-ED project was the winner of the 2017 International Society for Artificial Life Education and Outreach Award.

References

"Testing Darwin"

Discover Magazine ''Discover'' is an American general audience science magazine launched in October 1980 by Time Inc. It has been owned by Kalmbach Publishing since 2010. History Founding ''Discover'' was created primarily through the efforts of ''Time'' mag ...

, February 2005.

External links

Avida Software - GitHubAvida-ED Project - Robert T. PennockAn Avida Developer's SiteMSU Devolab website

Scientific publications featuring Avida

* C. Adami and C.T. Brown (1994), Evolutionary Learning in the 2D Artificial Life Systems Avida, in: R. Brooks, P. Maes (Eds.), Proc. Artificial Life IV, MIT Press, Cambridge, MA, p. 377-381. * R. E. Lenski, C. Ofria, T. C. Collier, C. Adami (1999). Genome Complexity, Robustness, and Genetic Interactions in Digital Organisms. ''Nature'' 400:661-664. * C.O. Wilke, J.L. Wang, C. Ofria, R.E. Lenski, and C. Adami (2001). Evolution of Digital Organisms at High Mutation Rate Leads To Survival of the Flattest. ''Nature'' 412:331-333. * R.E. Lenski, C. Ofria, R.T. Pennock, and C. Adami (2003). The Evolutionary Origin of Complex Features. ''Nature'' 423:139-145. * S.S. Chow, C.O. Wilke, C. Ofria, R.E. Lenski, and C. Adami (2004). Adaptive Radiation from Resource Competition in Digital Organisms. ''Science'' 305:84-86. * J. Clune, D. Misevic, C. Ofria, R.E. Lenski, S.F. Elena, and R. Sanjuán. Natural selection fails to optimize mutation rates for long-term adaptation on rugged fitness landscapes. PLoS Computational Biology 4(9): 2008. {{doi, 10.1371/journal.pcbi.1000187 * Clune J, Goldsby HJ, Ofria C, and Pennock RT (2011) Selective pressures for accurate altruism targeting: Evidence from digital evolution for difficult-to-test aspects of inclusive fitness theory. Proceedings of the Royal Society
pdfarchive
* Benjamin E. Beckmann, Philip K. McKinley, Charles Ofria (2007). Evolution of an adaptive sleep response in digital organisms. ''ECAL 2007'
pdf
Artificial life Artificial life models Digital organisms