Tierra

Astronomy

Computing and games

Film

Music

See also

Tierra (computer simulation)

Tierra is a computer simulation developed by ecologist Thomas S. Ray in the early 1990s in which computer programs compete for time (central processing unit (CPU) time) and space (access to main memory). In this context, the computer programs in Tierra are considered to be evolvable and can mutate, self-replicate and recombine. Tierra's virtual machine is written in C. It operates on a custom instruction set designed to facilitate code changes and reordering, including features such as jump to template (as opposed to the relative or absolute jumps common to most instruction sets).

Simulations

The basic Tierra model has been used to experimentally explore in silico the basic processes of evolutionary and ecological dynamics. Processes such as the dynamics of punctuated equilibrium, host-parasite co-evolution and density-dependent natural selection are amenable to investigation within the Tierra framework. A notable difference between Tierra and more conventional models of evolutionary computation, such as genetic algorithms, is that there is no explicit, or exogenous fitness function built into the model. Often in such models there is the notion of a function being "optimized"; in the case of Tierra, the fitness function is endogenous: there is simply survival and death.

Tierra (band)

Tierra is a Latin R&B band, originally from Los Angeles, California, that was first established in the 1970s by former El Chicano members Steve Salas (vocals) and his brother Rudy Salas (guitar). The other original members were Bobby Navarrete (reeds), Joey Guerra (keyboards), Steve Falomir (bass guitar), and Philip Madayag (drums) and Andre Baeza (percussion). Their biggest hit was the 1980 remake of The Intruders' 1967 hit "Together", written by Gamble & Huff, which reached #18 on the Billboard Hot 100, and #9 on the US Billboard R&B chart.

Background

Tierra has the distinction of being the first Latino band to have four songs on the national chart with two of them in the Top 100 at the same time.

Around 1973, Rudy and Steve Salas formed Tierra and their self-titled debut album was recorded. By the mid-1970s the band consisted of the Salas brothers, Rudy Villa on reeds, Kenny Romain on drums and latin-percussion, Conrad Lazano on bass, Aaron Ballesteros on drums and vocals, Alfred Rubaclava on bass and Leon Bisquera on keyboards. Around that time they recorded the album Stranded for the Salsoul records label.