Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If you need an accessible version of this item please contact JSTOR User Support

Estimating Species Richness: The Michaelis-Menten Model Revisited

Kim A. Keating and James F. Quinn
Oikos
Vol. 81, No. 2 (Mar., 1998), pp. 411-416
Published by: Wiley on behalf of Nordic Society Oikos
DOI: 10.2307/3547060
Stable URL: http://www.jstor.org/stable/3547060
Page Count: 6
  • Read Online (Free)
  • Cite this Item
If you need an accessible version of this item please contact JSTOR User Support
Estimating Species Richness: The Michaelis-Menten Model Revisited
Preview not available

Abstract

The Michaelis-Menten model has been widely used to estimate the richness (S) of species pools, but is largely untested. We tested whether (1) species accumulation curves follow the form predicted by the model, (2) the model gives unbiased estimates (Ŝ and B̂, respectively) of S and of the sample size, B, needed to detect S/2 species, and (3) performance is robust to community structure. Performance varied with community structure. For model communities with species-abundance distributions based on MacArthur's broken-stick model with 100 or 1000 species, deviations from predicted accumulation curves were slight, and Ŝ and B̂ were unbiased (P ≥ 0.18). For broken-stick communities with 10 species, Ŝ and B̂ overestimated S and B by an average of 17% and 63%, respectively (P < 0.001). For model communities with species-abundance distributions based on Tokeshi's (1990) random-fraction model with 10, 100, or 1000 species, deviations from predicted accumulation curves were large; on average, Ŝ underestimated S by 7-37% (P < 0.001), and (for S = 100 or 1000) B̂ underestimated B by 67-80% (P < 0.001). Vascular plant inventories (S = 42 to 99 species) also showed large deviations from predicted curves; on average, Ŝ underestimated S by 35% (P < 0.001) and B̂ underestimated B by 72% (P < 0.001). Because most natural communities are better described by the random-fraction than the broken-stick model, we suggest the Michaelis-Menten model will typically yield poor estimates of S. Moreover, we argue that accepted criteria for evaluating estimators of S are inadequate.

Page Thumbnails

  • Thumbnail: Page 
411
    411
  • Thumbnail: Page 
412
    412
  • Thumbnail: Page 
413
    413
  • Thumbnail: Page 
414
    414
  • Thumbnail: Page 
415
    415
  • Thumbnail: Page 
416
    416