Abstract
The neutral theory of S. P. Hubbell postulates a two-scale hierarchical
framework consisting of a metacommunity following the speciation¿drift equilibrium
characterized by the ``biodiversity number¿¿ h, and local communities following the
migration¿drift equilibrium characterized by the ``migration rate¿¿ m (or the ``fundamental
dispersal number¿¿ I). While Etienne¿s sampling formula allows simultaneous estimation of h
and m from a single sample of a local community, its applicability to a network of (rather
small) samples is questionable. We define here an alternative two-stage approach estimating h
from an adequate subset of the individuals sampled in the field (using Ewens¿ sampling
formula) and m from community samples (using Etienne¿s sampling formula). We compare its
results with the simultaneous estimation of h and m (one-stage estimation), for simulated
neutral samples and for 50 1-ha plots of evergreen forest in South India. The one-stage
approach exhibits problems of bias and of poor differentiability between high-h, low-m and
low-h, high-m solution domains. Conversely, the two-stage approach yielded reasonable
estimates and is to be preferred when several small, scattered plots are available instead of a
single large one.
Original language | English |
---|---|
Pages (from-to) | 2482-2488 |
Journal | Ecology |
Volume | 88 |
Issue number | 10 |
DOIs | |
Publication status | Published - 2007 |
Keywords
- biodiversity
- populations
- alleles
- evolution
- formula