干旱区生态环境知识资源中心(Arid): The Atacama toad (Rhinella atacamensis) exhibits an unusual clinal pattern of decreasing body size towards more arid environments

Arid

DOI	10.1186/s40850-021-00090-w
	The Atacama toad (Rhinella atacamensis) exhibits an unusual clinal pattern of decreasing body size towards more arid environments
	Duran, Felipe; Mendez, Marco A.; Correa, Claudio
通讯作者	Correa, C (corresponding author), Univ Concepcion, Fac Ciencias Nat & Oceanograf, Dept Zool, Lab Sistemat & Conservac Herpetozoos, Concepcion 1290, Chile.
来源期刊	BMC ZOOLOGY
EISSN	2056-3132
出版年	2021
卷号	6 期号:1
英文摘要	Background The causes of geographic variation of body size in ectotherms have generally been attributed to environmental variables. Research in amphibians has favored mechanisms that involve water availability as an explanation for the geographic variation of body size. However, there are few studies at intraspecific level on amphibians that inhabit desert or semi-desert environments, where hydric restrictions are stronger. Here, we describe and inquire as to the causes of the geographic variation of body size in the semi-desert toad Rhinella atacamensis, a terrestrial anuran that is distributed over 750 km along a latitudinal aridity gradient from the southern extreme of the Atacama Desert to the Mediterranean region of central Chile. We measured the snout-vent length of 315 adults from 11 representative localities of the entire distribution of the species. Then, using an information-theoretic approach, we evaluate whether the data support eight ecogeographic hypotheses proposed in literature. Results Rhinella atacamensis exhibits a gradual pattern of decrease in adult body size towards the north of its distribution, where the climate is more arid, which conforms to a Bergmann's cline. The best model showed that the data support the mean annual precipitation as predictor of body size, favoring the converse water availability hypothesis. Conclusions Most studies in amphibians show that adult size increases in arid environments, but we found a converse pattern to expected according to the hydric constraints imposed by this type of environment. The evidence in R. atacamensis favors the converse water availability hypothesis, whose mechanism proposes that the foraging activity determined by the precipitation gradient has produced the clinal pattern of body size variation. The variation of this trait could also be affected by the decreasing productivity that exists towards the north of the species distribution. In addition, we found evidence that both pattern and mechanism are independent of sex. Lastly, we suggest that behavioral traits, such as nocturnal habits, might also play an important role determining this differential response to aridity. Therefore, the support for the converse water availability hypothesis found in this study shows that amphibians can respond in different ways to water restrictions imposed by arid environments.
英文关键词	Bergmann's cline Ectotherm Atacama Desert Aridity gradient Information-theoretic approach Converse water availability hypothesis
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000694195100001
WOS关键词	BERGMANNS RULE ; GEOGRAPHIC-VARIATION ; ECOGEOGRAPHICAL RULES ; CONSERVATION BIOLOGY ; ARUNCO ANURA ; GRADIENTS ; FOLLOW ; AMPHIBIANS ; DIMORPHISM ; ECTOTHERMS
WOS类目	Zoology
WOS研究方向	Zoology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/362728
作者单位	[Duran, Felipe; Correa, Claudio] Univ Concepcion, Fac Ciencias Nat & Oceanograf, Dept Zool, Lab Sistemat & Conservac Herpetozoos, Concepcion 1290, Chile; [Mendez, Marco A.] Univ Chile, Fac Ciencias, Dept Ciencias Ecol, Lab Genet & Evoluc, Santiago, Chile
推荐引用方式 GB/T 7714	Duran, Felipe,Mendez, Marco A.,Correa, Claudio. The Atacama toad (Rhinella atacamensis) exhibits an unusual clinal pattern of decreasing body size towards more arid environments[J],2021,6(1).
APA	Duran, Felipe,Mendez, Marco A.,&Correa, Claudio.(2021).The Atacama toad (Rhinella atacamensis) exhibits an unusual clinal pattern of decreasing body size towards more arid environments.BMC ZOOLOGY,6(1).
MLA	Duran, Felipe,et al."The Atacama toad (Rhinella atacamensis) exhibits an unusual clinal pattern of decreasing body size towards more arid environments".BMC ZOOLOGY 6.1(2021).