Rapoport's Rule: Do climatic variability gradients shape range extent?

Abstract

The trend of increasing latitudinal range sizes of species towards higher latitudes, known as Rapoport's Rule, has been highly controversial in the literature since it was first proposed by Stevens in 1989. We contend that the question of interest is not whether general global patterns occur, nor whether they support or refute Rapoport's Rule, but whether the mechanism thought to underlie such patterns, the Climatic Variability Hypothesis, is supported. The Climatic Variability Hypothesis suggests that taxa originating from environmentally variable habitats, such as those at high latitudes and altitudes, should evolve wider environmental tolerances, and consequently establish wider distributions along climate gradients than taxa originating from relatively stable habitats. We applied a novel approach, incorporating measures of temperature variability across habitats within species' ranges into models of range size distributions, to determine whether the Climatic Variability Hypothesis applied to three clades of medium-sized ectotherms (lizards) distributed over Australia. Our results show that the Climatic Variability Hypothesis is supported, even in taxa that do not exhibit a traditional Rapoport Effect, due to complex, non-unidirectional climatic gradients in our study area. The results highlight the strong impact of climatic variability on species' physiological tolerances and their associated geographic distributions.

Knitting patterns of biodiversity, range size and body size in aquatic beetle faunas: significant relationships but slightly divergent drivers

“…For example, it is possible that the model of Stevens ' (1989) works only when larger range sizes would covary with reduced range overlap, and Šizling et al (2009) indeed showed that Rapoport's pattern will not generate the LDG if this assumption is not met. Support for the generality of Rapoport's rule has been quite variable (Gaston et al, 1998;Pintor et al, 2015;Tomašových et al, 2016): both findings for (Rohde et al, 1993) and against (Rohde, 1992) the existence of the rule have emerged. Support for the generality of Rapoport's rule has been quite variable (Gaston et al, 1998;Pintor et al, 2015;Tomašových et al, 2016): both findings for (Rohde et al, 1993) and against (Rohde, 1992) the existence of the rule have emerged.…”

Plant geographical range size and climate stability in China: Growth form matters

“…Additionally, species with smaller range sizes have higher extinction risk (Payne & Finnegan, 2007) and are likely to have lower ability to track current and future climate change (Sunday et al, 2015). However, the mechanisms underlying patterns of range size are still controversial, despite many studies on the geographical variation of range size (Gaston, 2003;Pintor, Schwarzkopf, & Krockenberger, 2015). However, the mechanisms underlying patterns of range size are still controversial, despite many studies on the geographical variation of range size (Gaston, 2003;Pintor, Schwarzkopf, & Krockenberger, 2015).…”

Empirical evidence for fast temperature-dependent body size evolution in rotifers

“…The phenomenon of achieving smaller size at maturity at higher temperature through phenotypic plasticity in ectotherms is known as the temperature-size rule (Atkinson, 1994), while the same pattern at a larger geographic scale through genetic adaptation was termed Bergmann's rule (Bergmann, 1847), now extended from its original focus on vertebrates to all organisms (Blanckenhorn & Demont, 2004). Several other rules describing a similar pattern from different points of view were proposed (Blackburn et al, 1999;McNab, 2010;Alho et al, 2011;Pintor et al, 2015), but the most important is that despite these different points of view, the observation of growing larger at colder temperatures is so common in nature.…”