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

Comparative Methods at the Species Level: Geographic Variation in Morphology and Group Size in Grey-Crowned Babblers (Pomatostomus temporalis)

Scott V. Edwards and Mark Kot
Evolution
Vol. 49, No. 6 (Dec., 1995), pp. 1134-1146
DOI: 10.2307/2410438
Stable URL: http://www.jstor.org/stable/2410438
Page Count: 13
  • Get Access
  • Read Online (Free)
  • Download ($4.00)
  • Cite this Item
If you need an accessible version of this item please contact JSTOR User Support
Comparative Methods at the Species Level: Geographic Variation in Morphology and Group Size in Grey-Crowned Babblers (Pomatostomus temporalis)
Preview not available

Abstract

We show that a new comparative method that sheds light on evolutionary trends among species may also illuminate trends within species. This finding comes from a phylogenetic autocorrelation analysis of morphological traits among individuals sampled from ten populations of a cooperatively breeding songbird, the Grey-crowned Babbler (Pomatostomus temporalis). Highly variable mitochondrial DNA (mtDNA) sequences from both the eastern (Pomatostomus temporalis temporalis) and western (Pomatostomus temporalis rubeculus) lineages were used to define genetic distances among 120 individuals and to estimate correlations among individuals in wing length, tarsus length, and body weight via an intraspecific weighting matrix. The autoregressive model effectively removed intraspecific correlations for all three morphological variables, and the proportion of the total phenotypic variance due to genealogical relationships varied from 0.68 (weight) to 0.23 (tarsus). The analysis revealed correlations among the specific components of traits, in which none were previously detected (type-I error) and diminished correlations that appeared strong when phylogeny was ignored. Group size was the only trait for which the autoregressive model failed to remove intraspecific correlations, a result likely due to the plasticity, convergence, and clinal variation in this trait in both the eastern and western lineages. The autocorrelation analysis weakened significant negative correlations between group size and total values for wing length and body weight, but the interpretation of this result depends on the adaptive significance ascribed to the "phylogenetic component" of trait values removed by the analysis. Comparative methods employing distance matrices are one useful way of summarizing the pattern of nonhierarchical relationships among conspecific individuals ("tokogenetic" relationships, sensu Hennig).

Page Thumbnails

  • Thumbnail: Page 
1134
    1134
  • Thumbnail: Page 
1135
    1135
  • Thumbnail: Page 
1136
    1136
  • Thumbnail: Page 
1137
    1137
  • Thumbnail: Page 
1138
    1138
  • Thumbnail: Page 
1139
    1139
  • Thumbnail: Page 
1140
    1140
  • Thumbnail: Page 
1141
    1141
  • Thumbnail: Page 
1142
    1142
  • Thumbnail: Page 
1143
    1143
  • Thumbnail: Page 
1144
    1144
  • Thumbnail: Page 
1145
    1145
  • Thumbnail: Page 
1146
    1146