page_title: Relative species abundance
section_title: Distribution plots
hierarchical_section_title: Relative species abundance / Introduction / Distribution plots
caption_attribution_description: English: Rank-abundance diagram ("Whittaker plot") of beetles sampled from the river Thames showing a slight "s"-shape. (derived from data presented in Magurran (2004) and collected by Williams (1964))
context_page_description: Relative species abundance is a component of biodiversity and refers to how common or rare a species is relative to other species in a defined location or community. Relative abundance is the percent composition of an organism of a particular kind relative to the total number of organisms in the area. Relative species abundances tend to conform to specific patterns that are among the best-known and most-studied patterns in macroecology. Different populations in a community exist in relative proportions; this idea is known as relative abundance.
context_section_description: Relative species abundance distributions are usually graphed as frequency histograms ("Preston plots"; Figure 2) or rank-abundance diagrams ("Whittaker Plots"; Figure 3).
  Frequency histogram (Preston plot):
  x-axis: logarithm of abundance bins (historically log₂ as a rough approximation to the natural logarithm)
  y-axis: number of species at given abundance
  Rank-abundance diagram (Whittaker plot):
  x-axis: species list, ranked in order of descending abundance (i.e. from common to rare)
  y-axis: logarithm of % relative abundance
  When plotted in these ways, relative species abundances from wildly different data sets show similar patterns: frequency histograms tend to be right-skewed (e.g. Figure 2) and rank-abundance diagrams tend to conform to the curves illustrated in Figure 4.
caption: Figure 3. Whittaker plot of beetles sampled from the river Thames showing a slight "s"-shape.[2][3]
exif: {}