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Flexibility is everything: prey capture throughout the seasonal habitat switches in the smooth newt Lissotriton vulgaris.

Heiss E, Aerts P, Van Wassenbergh S - Org. Divers. Evol. (2014)

Bottom Line: Due to the different biophysical demands on the whole organism in water and air, such transitions require major changes of many physiological functions, including feeding.Accordingly, the capability to modulate the pre-programmed chain of prey-capture movements might be essential to maintain performance in a new environment.Our results indicate that newts exhibit a high degree of seasonal flexibility of the prey-capture behavior.

View Article: PubMed Central - PubMed

Affiliation: Institute of Systematic Zoology and Evolutionary Biology, Friedrich-Schiller-University Jena, Erbertstr. 1, 07743 Jena, Germany ; Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium ; Department of Integrative Zoology, University of Vienna, Althanstr. 14, 1090 Vienna, Austria.

ABSTRACT

Transitions between aquatic and terrestrial habitats are significant steps in vertebrate evolution. Due to the different biophysical demands on the whole organism in water and air, such transitions require major changes of many physiological functions, including feeding. Accordingly, the capability to modulate the pre-programmed chain of prey-capture movements might be essential to maintain performance in a new environment. Newts are of special interest in this regard as they show a multiphasic lifestyle where adults change seasonally between an aquatic and a terrestrial stage. For instance, the Alpine newt is capable of using tongue prehension to feed on land only when in the terrestrial stage, but still manages to suction feed if immersed whilst in terrestrial stage. During the aquatic stage, terrestrial feeding always involved grasping prey by the jaws. Here, we show that this seasonal shift in feeding behavior is also present in a species with a shorter terrestrial stage, the smooth newt Lissotriton vulgaris. Behavioral variability increases when animals change from aquatic to terrestrial strikes in the aquatic stage, but prey-capture movements seem to be generally well-coordinated across the feeding modes. Only suction feeding in the terrestrial stage was seldom performed and appeared uncoordinated. Our results indicate that newts exhibit a high degree of seasonal flexibility of the prey-capture behavior. The similarity between movement patterns of suction feeding and terrestrial feeding suggests that only relatively subtle neuromotoric adjustments to the ancestral, suction-feeding motor program are required to successfully feed in the new environment.

No MeSH data available.


Related in: MedlinePlus

Scatter plot of the first two principal components. Principal component 1 (PC1) and principal component 2 (PC2) are derived from the 12 kinematic variables to illustrate the relationship among kinematic patterns for the four feeding modes coded by symbols and the ten individuals coded by color. Each data point represents one feeding event, and the ellipses indicate 95 % confidence interval in the four feeding modes. PC1 explains 57 % and PC2 explains 15.5 % of the total variance. See Table 3 for complete loadings of each principal component
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Fig4: Scatter plot of the first two principal components. Principal component 1 (PC1) and principal component 2 (PC2) are derived from the 12 kinematic variables to illustrate the relationship among kinematic patterns for the four feeding modes coded by symbols and the ten individuals coded by color. Each data point represents one feeding event, and the ellipses indicate 95 % confidence interval in the four feeding modes. PC1 explains 57 % and PC2 explains 15.5 % of the total variance. See Table 3 for complete loadings of each principal component

Mentions: Figure 4 shows the multivariate dispersion of kinematics among the four feeding modes and the ten individuals on the first two principal components, and the loadings of the variables on components 1–3 are given in Table 3. Suction feeding in the aquatic stage almost entirely overlaps in kinematic space with suction feeding in the terrestrial stage. Jaw prehension shows a distinct distribution pattern but overlaps with all other three behaviors to a certain degree. In fact, jaw prehension lies between suction feeding in both stages and tongue prehension. Tongue prehension shows no overlapping area with suction feeding in both stages but a small area of kinematic space is shared with jaw prehension. By contrast, the dispersion of individuals in kinematic space broadly overlaps and is clearly related to the feeding modes (Fig. 4: especially shown by the individual coded in red).Fig. 4


Flexibility is everything: prey capture throughout the seasonal habitat switches in the smooth newt Lissotriton vulgaris.

Heiss E, Aerts P, Van Wassenbergh S - Org. Divers. Evol. (2014)

Scatter plot of the first two principal components. Principal component 1 (PC1) and principal component 2 (PC2) are derived from the 12 kinematic variables to illustrate the relationship among kinematic patterns for the four feeding modes coded by symbols and the ten individuals coded by color. Each data point represents one feeding event, and the ellipses indicate 95 % confidence interval in the four feeding modes. PC1 explains 57 % and PC2 explains 15.5 % of the total variance. See Table 3 for complete loadings of each principal component
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4470538&req=5

Fig4: Scatter plot of the first two principal components. Principal component 1 (PC1) and principal component 2 (PC2) are derived from the 12 kinematic variables to illustrate the relationship among kinematic patterns for the four feeding modes coded by symbols and the ten individuals coded by color. Each data point represents one feeding event, and the ellipses indicate 95 % confidence interval in the four feeding modes. PC1 explains 57 % and PC2 explains 15.5 % of the total variance. See Table 3 for complete loadings of each principal component
Mentions: Figure 4 shows the multivariate dispersion of kinematics among the four feeding modes and the ten individuals on the first two principal components, and the loadings of the variables on components 1–3 are given in Table 3. Suction feeding in the aquatic stage almost entirely overlaps in kinematic space with suction feeding in the terrestrial stage. Jaw prehension shows a distinct distribution pattern but overlaps with all other three behaviors to a certain degree. In fact, jaw prehension lies between suction feeding in both stages and tongue prehension. Tongue prehension shows no overlapping area with suction feeding in both stages but a small area of kinematic space is shared with jaw prehension. By contrast, the dispersion of individuals in kinematic space broadly overlaps and is clearly related to the feeding modes (Fig. 4: especially shown by the individual coded in red).Fig. 4

Bottom Line: Due to the different biophysical demands on the whole organism in water and air, such transitions require major changes of many physiological functions, including feeding.Accordingly, the capability to modulate the pre-programmed chain of prey-capture movements might be essential to maintain performance in a new environment.Our results indicate that newts exhibit a high degree of seasonal flexibility of the prey-capture behavior.

View Article: PubMed Central - PubMed

Affiliation: Institute of Systematic Zoology and Evolutionary Biology, Friedrich-Schiller-University Jena, Erbertstr. 1, 07743 Jena, Germany ; Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium ; Department of Integrative Zoology, University of Vienna, Althanstr. 14, 1090 Vienna, Austria.

ABSTRACT

Transitions between aquatic and terrestrial habitats are significant steps in vertebrate evolution. Due to the different biophysical demands on the whole organism in water and air, such transitions require major changes of many physiological functions, including feeding. Accordingly, the capability to modulate the pre-programmed chain of prey-capture movements might be essential to maintain performance in a new environment. Newts are of special interest in this regard as they show a multiphasic lifestyle where adults change seasonally between an aquatic and a terrestrial stage. For instance, the Alpine newt is capable of using tongue prehension to feed on land only when in the terrestrial stage, but still manages to suction feed if immersed whilst in terrestrial stage. During the aquatic stage, terrestrial feeding always involved grasping prey by the jaws. Here, we show that this seasonal shift in feeding behavior is also present in a species with a shorter terrestrial stage, the smooth newt Lissotriton vulgaris. Behavioral variability increases when animals change from aquatic to terrestrial strikes in the aquatic stage, but prey-capture movements seem to be generally well-coordinated across the feeding modes. Only suction feeding in the terrestrial stage was seldom performed and appeared uncoordinated. Our results indicate that newts exhibit a high degree of seasonal flexibility of the prey-capture behavior. The similarity between movement patterns of suction feeding and terrestrial feeding suggests that only relatively subtle neuromotoric adjustments to the ancestral, suction-feeding motor program are required to successfully feed in the new environment.

No MeSH data available.


Related in: MedlinePlus