Paper no. 2: Distribution of the species over the area
by O. Arrhenius
by Tanner Hawkins
Ethan P. White is a researcher at Utah State
University. His research interests are on “data-intensive questions in ecology,
using large ecological datasets, advanced statistical/machine learning methods,
and theoretical modeling to understand ecological patterns.”
Olof Arrhenius (1895-1977) was a Swedish biochemist
and botanist. His paper on the Species Area Relationship was highly influential
in the field of ecology.
The Species
Area Relationship (SAR) is one of the most prominent unexplained patterns in
ecology. This pattern is best described in Arrehenius’ 1921 paper, in which he
related species area as a power function of the number of species. Arrhenius
had no rationale for why this was the case, he just wanted to see if the data
fit. Not only did it fit his data, but it proved to be consistent throughout
various ecosystems, and no one's quite sure why.
Arrhenius, in
collaboration with Jaccard Novelles, surveyed five sites in Switzerland: a
local grass-meadow, a meadow in the Alps, and two Archipelagos near Stockholm,
and a leaf-meadow near Aland. In most the power function was for the most part
consistent across sites.
These results
suggested an emergent pattern, and later studies seem to corroborate this. This
relationship is foundational to island biogeography and conservation biology,
among other things, but there is still a lot that we don’t know. The lack of a
reason behind why this relationship is the way it is means that SAR research is
still very much alive.
Questions:
Is this SAR constant for nonplants such as
animals and microbes?
Are there
limits for land area or number of species where Arrhenius’ equation no longer
fits, such as microscopic ecosystems or ecosystems with very large areas?
