干旱区生态环境知识资源中心(Arid): Dining intertidally: diet, energetics, and osmotic relations of two shoreline-foraging tropidurid lizard species

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DOI	10.2994/SAJH-D-19-00098.1
	Dining intertidally: diet, energetics, and osmotic relations of two shoreline-foraging tropidurid lizard species
	Nagy, Kenneth A.; Guerra-Correa, Carlos; Shoemaker, Vaughan H.
通讯作者	Nagy, KA (corresponding author), Univ Calif Los Angeles, Dept Ecol & Evolutionary Biol, 621 CE Young Dr South, Los Angeles, CA 90095 USA.
来源期刊	SOUTH AMERICAN JOURNAL OF HERPETOLOGY
ISSN	1808-9798
出版年	2021
卷号	20 期号:1 页码:8-16
英文摘要	Because marine environments present potentially stressful hyperosmotic and hypersaline situations for reptiles, those species that live in or near seawater are of special interest regarding their feeding and drinking behavior and their osmotic and ionic regulatory physiology. We determined diets, field metabolic rates (FMRs), rates of water influx and efflux, and aspects of osmoregulation in intertidally foraging populations of two congeneric species of tropidurid lizards: Microlophus albemarlensis in the Galapagos Islands and M. atacamensis in the Atacama Desert of northern Chile. Male M. albemarlensis ate only crabs, specializing on the legs of small Sally Lightfoot crabs, while the much smaller females favored insects but ate whole small crabs as well. In contrast, M. atacamensis males and (the also smaller) females both ate mainly seaweed, along with some crabs and insects. Adults of both species were maintaining constant body masses on these hyperosmotic diets, although subadult M. atacamensis lost mass during our study. FMRs of both species, which were hypothesized to be high due to presumed extra energy costs of osmoregulation, were actually comparatively low, averaging 65% (M. albemarlensis) and 78% (M. atacamensis) of expected FMRs for lizards of their body mass. However, water flux rates were typical of free-living reptiles, averaging 79 and 116%, respectively, of predicted rates. Osmotic concentrations in blood plasma and urine of M. albemarlensis were typical of lizards in general, but plasma of M. atacamensis was about 50% higher (498 +/- 42 mOsm), perhaps reflecting an unavoidable consequence of, or even an adaptation to, their higher dietary osmolyte content (1,680 mOsm in sap of dietary seaweed). Other possible adaptations that facilitate exploitation of unusual diet items and ingestion of seawater are discussed. In particular, the roles of nasal salt glands and urinary precipitates in osmoregulation and ion homeostasis of both species are likely important but are currently unknown and should be studied.
英文关键词	Atacama Desert Energy conservation Galapagos Hyperosmotic stress Microlophus Seaweed consumption
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000692603900002
WOS关键词	GALAPAGOS MARINE IGUANA ; MICROLOPHUS-ATACAMENSIS ; POTENTIAL ERRORS ; WATER ; OSMOREGULATION ; COSTS ; ANIMALS ; CONSUMPTION ; SECRETION ; EXCRETION
WOS类目	Zoology
WOS研究方向	Zoology
来源机构	University of California, Los Angeles
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/364725
作者单位	[Nagy, Kenneth A.] Univ Calif Los Angeles, Dept Ecol & Evolutionary Biol, 621 CE Young Dr South, Los Angeles, CA 90095 USA; [Guerra-Correa, Carlos] Univ Antofagasta, Ctr Reg Estudios & Educ Ambiental, Antofagasta, Chile; [Shoemaker, Vaughan H.] Univ Calif Riverside, Dept Biol, Riverside, CA 92502 USA
推荐引用方式 GB/T 7714	Nagy, Kenneth A.,Guerra-Correa, Carlos,Shoemaker, Vaughan H.. Dining intertidally: diet, energetics, and osmotic relations of two shoreline-foraging tropidurid lizard species[J]. University of California, Los Angeles,2021,20(1):8-16.
APA	Nagy, Kenneth A.,Guerra-Correa, Carlos,&Shoemaker, Vaughan H..(2021).Dining intertidally: diet, energetics, and osmotic relations of two shoreline-foraging tropidurid lizard species.SOUTH AMERICAN JOURNAL OF HERPETOLOGY,20(1),8-16.
MLA	Nagy, Kenneth A.,et al."Dining intertidally: diet, energetics, and osmotic relations of two shoreline-foraging tropidurid lizard species".SOUTH AMERICAN JOURNAL OF HERPETOLOGY 20.1(2021):8-16.