TY - JOUR

T1 - Scale-dependence in geographical variation in a freshwater gastropod across Palearctic

AU - Vinarski, Maxim V.

AU - Kramarenko, Sergei S.

PY - 2019/4/3

Y1 - 2019/4/3

N2 - The reality of spatial clinal variation in morphological traits of freshwater pulmonate snails (Gastropoda: Pulmonata) has repeatedly been questioned or totally discounted. There is a lack of sound statistical evidence in the articles hitherto published on this subject supporting these claims. Here, by means of different analytical methods (analysis of spatial autocorrelation, linear regression analysis, canonical correlation analysis and others), we demonstrate that shell variation in the dwarf pond snail, Galba truncatula, is patterned in space throughout the northern and central Palearctic, with latitudinally-oriented clines in body size and in some shell proportions. Shell size in G. truncatula decreases with latitude and temperature, representing a special case of converse Bergmann cline. However, the temperature itself is hardly the main driver of shell size variation. It is argued that the shorter growing seasons at high latitudes may represent a better explanation for the observed trend. Shell proportions in the dwarf pond snails vary weakly at the macrogeographic scale, being spatially patterned at lower (mesogeographic) scales around 1200–1500 km. In general, spatial variation in G. truncatula shell size is decoupled from variation in shell shape, demonstrating clear scale-dependence similar to that found in different species of terrestrial (non-aquatic) pulmonate snails.

AB - The reality of spatial clinal variation in morphological traits of freshwater pulmonate snails (Gastropoda: Pulmonata) has repeatedly been questioned or totally discounted. There is a lack of sound statistical evidence in the articles hitherto published on this subject supporting these claims. Here, by means of different analytical methods (analysis of spatial autocorrelation, linear regression analysis, canonical correlation analysis and others), we demonstrate that shell variation in the dwarf pond snail, Galba truncatula, is patterned in space throughout the northern and central Palearctic, with latitudinally-oriented clines in body size and in some shell proportions. Shell size in G. truncatula decreases with latitude and temperature, representing a special case of converse Bergmann cline. However, the temperature itself is hardly the main driver of shell size variation. It is argued that the shorter growing seasons at high latitudes may represent a better explanation for the observed trend. Shell proportions in the dwarf pond snails vary weakly at the macrogeographic scale, being spatially patterned at lower (mesogeographic) scales around 1200–1500 km. In general, spatial variation in G. truncatula shell size is decoupled from variation in shell shape, demonstrating clear scale-dependence similar to that found in different species of terrestrial (non-aquatic) pulmonate snails.

KW - Body size

KW - clinal variation

KW - multi-scale approach

KW - pulmonate snails

KW - spatial autocorrelation

KW - BODY-SIZE

KW - PATTERNS

KW - PULMONATA

KW - SPATIAL-ANALYSIS

KW - HOSTS

KW - MOLLUSCA

KW - TEMPERATURE

KW - GALBA

KW - LAND SNAILS

KW - DIFFERENTIATION

UR - http://www.scopus.com/inward/record.url?scp=85052070722&partnerID=8YFLogxK

UR - http://www.mendeley.com/research/scaledependence-geographic-variation-freshwater-gastropod-across-palearctic

U2 - 10.1080/13235818.2018.1497570

DO - 10.1080/13235818.2018.1497570

M3 - Article

VL - 39

SP - 159

EP - 170

JO - Molluscan Research

JF - Molluscan Research

SN - 1323-5818

IS - 2

ER -