Can a species change into an entirely new species?

Define species. If you mean separation in ability to mate and produce offspring, this has been observed in cases of protracted adaptation, sometimes referred to as micro evolution. But grass evolves to grass, fish to fish. The definition conundrum continues with speciation. read more

An important characteristic of a community and the ecosystem to which it belongs is --- the number of different species it contains (species richness) combined with the relative abundance of individuals within each of those species (species evenness). read more