Geography Reference
In-Depth Information
3. Third criterion (
fig. 4.15c
)
: It is not required that all the grid cells of the set
have identical species composition, but only species occurring in each one
of the cells contribute to the score.
4. Fourth criterion (
fig. 4.15d
)
: A species may be absent from a given cell but
still contribute to the score. Only a species that is evenly distributed in the
area satisfies this criterion.
Szumik and Goloboff (2004) developed an endemicity value that gives
weight to each species, considering its adjustment to the evaluated area.
The degree of adjustment between the distributional area of each species
and the area of endemism under evaluation depends on the relationship
between the number of grid cells where it is found and the total number of
grid cells. Additionally, the endemicity value increases with the number of
grid cells where the presence of the species is assumed or inferred and de-
creases with the number of grid cells outside the area of endemism where
the species is observed or assumed to be present (Szumik and Goloboff
2004).
