Problems with the claim of ecotype and taxon status of the wolf in the Great Lakes region

Authors

Matthew A. Cronin, University of Alaska, FairbanksFollow
L. David Mech, USGS Northern Prairie Wildlife Research CenterFollow

Date of this Version

2009

Citation

Molecular Ecology (2009) 18, pp. 4991–4993.

Comments

U.S. government work.

Abstract

Koblmuller et al. (2009) analyzed molecular genetic data of the wolf in the Great Lakes (GL) region of the USA and concluded that the animal was a unique ecotype of grey wolf and that genetic data supported the population as a discrete wolf taxon. However, some of the literature that the researchers used to support their position actually did not, and additional confusion arises from indefinite use of terminology. Herein, we discuss the problems with designation of a wolf population as a taxon or ecotype without proper definition and assessment of criteria.

Koblmuller et al. (2009) wrote ‘The GL wolf is morphologically distinct from both western grey wolves (Canis lupus) and coyotes (Canis latrans) (Nowak 2002)’. However, Nowak (2002) did not draw this conclusion nor did his plots of the first and second canonical variables show this (Nowak 2002: Figures 6 and 8). Nowak’s (2002: Figure 8) could be interpreted as indicating either overlap between western C. lupus and wolves from Michigan or a continuum between the two types. Furthermore, similar analyses by Nowak (2009: Figures 15.1 and 15.2) show complete overlap between Minnesota wolves and western wolves and partial overlap between Michigan wolves and Minnesota and western wolves. Regardless, skull morphology (size and dimensions) is influenced by genetics and environment. Morphological variation is not a definitive indicator of phylogenetic ancestry (and hence taxonomy) or local adaptation (and hence ecotype status) without controlled experimentation. Morphology may indicate ancestry (and be useful in taxonomy—e.g. domestic animal breeds differ in morphology because of ancestry) or environment (and reflect ecology—e.g. nutrition will influence body size), but these factors must be empirically assessed.