Cline (biology) - Gradient Analysis

Gradient Analysis

In ecology, spatial clines have led to gradient analysis where the abundance and distribution of organisms is rendered by sinusoidal curves on the plane. From these curves can be extracted that populations occupy zones of maximum and minimum presence, according to their special needs and tolerances imposed by their environment.

Typically, a well-marked cline does not allow for a delineation of subspecies, as it is then impossible, by definition, to draw any further clear dividing lines between populations. In population genetics, a cline could include a spectrum of subspecies, as allele and haplotype frequencies tend to vary over a larger space; moreover, in evolution, genetic lineage sorting usually lags behind the establishment of locally-differentiated phenotypes. Regardless, in neither case will such a variation yield different species, as long as the populations, though geographically spread, can interbreed one with another.