Quality of basic data and method used to identify shape affect the perception of species richness altitude relationship in arthopods.

WERENKRAUT, VICTORIA; ADRIANA, RUGGIERO

ECOLOGY

ECOLOGICAL SOC AMER

Año: 2011 vol. 92 p. 253 - 260

0012-9658

Abstract. We compiled 109 species richness–altitude (SRA) relationships in arthropods totest the hypothesis that identification of shape and robustness of pattern are contingent on theselection of studies included in meta-analysis. We used attributes of their sampling design todistinguish three subsets of data according to stringent, intermediate, and lax selection criteria.We tested (1) whether uncertainty over identification of shape increases as the criteria ofinclusion of studies relaxes and (2) whether studies that conform to stringent selection criteriashow robustness in SRA patterns to variation in method used to identify shape. We identifiedthe shape of each SRA relationship using statistical and visual methods; data sets thatsuggested several shapes as equally likely were sorted out by consensus. Arthropods suggestedmultiple forms in the SRA relationship, with predominance of hump-shaped patterns in thestringent subset. Uncertainty over identification of shape increased after application ofintermediate and lax selection criteria. The method of analysis interacted with the quality ofbasic data to influence the relative distribution of patterns. We concluded that the gathering oflarge quantities of data is insufficient and that critical evaluation of literature is crucial to inferwith confidence the general shape of ecological patterns in meta-analysis.