scholarly journals A toothless dwarf dolphin (Odontoceti: Xenorophidae) points to explosive feeding diversification of modern whales (Neoceti)

2017 ◽  
Vol 284 (1861) ◽  
pp. 20170531 ◽  
Author(s):  
Robert W. Boessenecker ◽  
Danielle Fraser ◽  
Morgan Churchill ◽  
Jonathan H. Geisler
Keyword(s):  
Phylogenetic Analysis ◽  
South Carolina ◽  
Feeding Behaviour ◽  
Stabilizing Selection ◽  
Suction Feeding ◽  
Feeding Mode ◽  
Milk Teeth ◽  
Feeding Morphology ◽  
Tooth Count

Toothed whales (Odontoceti) are adapted for catching prey underwater and possess some of the most derived feeding specializations of all mammals, including the loss of milk teeth (monophyodonty), high tooth count (polydonty), and the loss of discrete tooth classes (homodonty). Many extant odontocetes possess some combination of short, broad rostra, reduced tooth counts, fleshy lips, and enlarged hyoid bones—all adaptations for suction feeding upon fishes and squid. We report a new fossil odontocete from the Oligocene (approx. 30 Ma) of South Carolina ( Inermorostrum xenops , gen. et sp. nov.) that possesses adaptations for suction feeding: toothlessness and a shortened rostrum (brevirostry). Enlarged foramina on the rostrum suggest the presence of enlarged lips or perhaps vibrissae. Phylogenetic analysis firmly places Inermorostrum within the Xenorophidae, an early diverging odontocete clade typified by long-snouted, heterodont dolphins. Inermorostrum is the earliest obligate suction feeder within the Odontoceti, a feeding mode that independently evolved several times within the clade. Analysis of macroevolutionary trends in rostral shape indicate stabilizing selection around an optimum rostral shape over the course of odontocete evolution, and a post-Eocene explosion in feeding morphology, heralding the diversity of feeding behaviour among modern Odontoceti.

scholarly journals A toothless dwarf dolphin (Odontoceti: Xenorophidae) points to explosive feeding diversification of modern whales (Neoceti)

2017 ◽  
Author(s):  
Robert Boessenecker ◽  
Danielle Fraser ◽  
Morgan Churchill ◽  
Jonathan Geisler
Keyword(s):  
Phylogenetic Analysis ◽  
South Carolina ◽  
Feeding Behaviour ◽  
Stabilizing Selection ◽  
Suction Feeding ◽  
Feeding Mode ◽  
Milk Teeth ◽  
Feeding Morphology ◽  
Tooth Count

Toothed whales (Odontoceti) are adapted for catching prey underwater and possess some of the most derived feeding specializations of all mammals, including the loss of milk teeth (monophyodonty), high tooth count (polydonty), and the loss of discrete tooth classes (homodonty). Many extant odontocetes possess some combination of short, broad rostra, reduced tooth counts, fleshy lips, and enlarged hyoid bones - all adaptations for suction feeding upon fish and squid. We report a new fossil odontocete from the Oligocene (~30 Ma) of South Carolina (Inermorostrum xenops, gen. et sp. nov.) that possesses adaptations for suction feeding: toothlessness and a shortened rostrum (brevirostry). Enlarged foramina on the rostrum suggest the presence of enlarged lips or perhaps vibrissae. Phylogenetic analysis firmly places Inermorostrum within the Xenorophidae, an early diverging odontocete clade typified by long-snouted, heterodont dolphins. Inermorostrum is the earliest obligate suction feeder within the Odontoceti, a feeding mode that independently evolved several times within the clade. Analysis of macroevolutionary trends in rostral shape indicate stabilizing selection around an optimum rostral shape over the course of odontocete evolution, and a post-Eocene explosion in feeding morphology, heralding the diversity of feeding behaviour amongst modern Odontoceti.

scholarly journals Ontogeny of feeding morphology and kinematics in juvenile fishes: a case study of the cottid fish Clinocottus analis

1996 ◽  
Vol 199 (9) ◽  
pp. 1961-1971
Author(s):  
A Cook
Keyword(s):  
High Speed ◽  
Prey Capture ◽  
Least Squares Regression ◽  
Suction Feeding ◽  
Juvenile Period ◽  
Feeding Mode ◽  
Feeding Morphology ◽  
Suction Index ◽  
And Behavior

The development of feeding morphology, kinematics and behavior was examined in the juveniles of the cottid fish Clinocottus analis. The attacks of 18 juvenile C. analis, between 17.59 mm and 42.15 mm in standard length (SL), feeding on brown worms were filmed using high-speed video. Feeding mode, ram- or suction-dominated, kinematic variables and morphology were quantified and compared over the juvenile period. The analysis of these three factors was based on the following questions: (1) do they change over ontogeny; (2) how do their values compare with those of larvae, juveniles and adults of other species; and (3) what is the level of stereotypy, as measured by the variance in these factors, at this stage in ontogeny and does it change? Small C. analis juveniles have the small gape and large buccal cavity of a suction feeder, and this morphology becomes more pronounced as they become larger. The kinematic variables of C. analis juveniles are similar to those of adult suction-feeding cottids and least-squares regression analysis showed significant changes in only two variables (time to prey capture and absolute attack predator­prey distance) over the juvenile period. Feeding mode, as measured by the ram-suction index, shows an increase in the suction component of the strike with increasing size. This study demonstrates that, in C. analis, suction feeding behavior develops during the juvenile period. Within the juvenile stage, morphology, prey-capture kinematics and feeding mode are not tightly linked ontogenetically such that suction-feeder kinematics (short predator­prey distance and low attack velocity) and basic morphology (small gape, large buccal volume) develop much earlier than the employment of a large suction component during the strike.

scholarly journals More than Meets the Eye: Functionally Salient Changes in Internal Bone Architecture Accompany Divergence in Cichlid Feeding Mode

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
R. Craig Albertson ◽  
W. James Cooper ◽  
Kenneth A. Mann
Keyword(s):  
Genetic Basis ◽  
Dominant Mode ◽  
Bone Architecture ◽  
Foraging Strategies ◽  
Craniofacial Skeleton ◽  
Suction Feeding ◽  
Foraging Mode ◽  
Feeding Mode ◽  
Adaptive Radiations ◽  
African Cichlids

African cichlids have undergone extensive and repeated adaptive radiations in foraging habitat. While the external morphology of the cichlid craniofacial skeleton has been studied extensively, biomechanically relevant changes to internal bone architecture have been largely overlooked. Here we explore two fundamental questions: (1) Do changes in the internal architecture of bone accompany shifts in foraging mode? (2) What is the genetic basis for this trait? We focus on the maxilla, which is an integral part of the feeding apparatus and an element that should be subjected to significant bending forces during biting. Analyses of μCT scans revealed clear differences between the maxilla of two species that employ alternative foraging strategies (i.e., biting versus suction feeding). Hybrids between the two species exhibit maxillary geometries that closely resemble those of the suction feeding species, consistent with a dominant mode of inheritance. This was supported by the results of a genetic mapping experiment, where suction feeding alleles were dominant to biting alleles at two loci that affect bone architecture. Overall, these data suggest that the internal structure of the cichlid maxilla has a tractable genetic basis and that discrete shifts in this trait have accompanied the evolution of alternate feeding modes.

scholarly journals Cytokinin-mediated leaf manipulation by a leafminer caterpillar

2007 ◽  
Vol 3 (3) ◽  
pp. 340-343 ◽  
Author(s):  
David Giron ◽  
Wilfried Kaiser ◽  
Nadine Imbault ◽  
Jérôme Casas
Keyword(s):  
Plant Physiology ◽  
Feeding Behaviour ◽  
Adaptive Significance ◽  
Plant Defences ◽  
Selective Feeding ◽  
Feeding Mode ◽  
Leaf Mining ◽  
Galling Insects ◽  
Nutritional Benefits

A large number of hypotheses have been proposed to explain the adaptive significance and evolution of the endophagous-feeding mode, nutritional benefits being considered to be one of the main advantages. Leaf-mining insects should feed on most nutritional tissues and avoid tissues with high structural and/or biochemical plant defences. This selective feeding behaviour could furthermore be reinforced by manipulating the plant physiology, as suggested by the autumnal formation of ‘green islands’ around mining caterpillars in yellow leaves. The question we address here is how such metabolic manipulation occurs and what the nutritional consequences for the insect are. We report a large accumulation of cytokinins in the mined tissues which is responsible for the preservation of functional nutrient-rich green tissues at a time when leaves are otherwise turning yellow. The analogy with other plant manipulating organisms, in particular galling insects, is striking.

scholarly journals A complex performance landscape for suction-feeding reveals constraints and adaptations in a population of reef damselfish

2017 ◽  
Author(s):  
Tal Keren ◽  
Moshe Kiflawi ◽  
Christopher H Martin ◽  
Victor China ◽  
Ofri Mann ◽  
...  
Keyword(s):  
Morphological Traits ◽  
Prey Capture ◽  
Mechanistic Model ◽  
Adaptive Landscape ◽  
Phenotypic Traits ◽  
Stabilizing Selection ◽  
Suction Feeding ◽  
Feeding Performance ◽  
Genetic Constraints ◽  
A Performance

AbstractThe ability to predict how multiple traits interact in determining performance is key to understanding the evolution of complex functional systems. Similar to Simpson’s adaptive landscape, which describes the fitness consequences of varying morphological traits, performance landscapes depict the performance consequences of varying morphological traits. Mapping the population’s location with respect to the topographic features of the landscape could inform us on the selective forces operating on the traits that underlie performance. Here, we used a mechanistic model derived from first principles of hydrodynamics to construct a hypothetical performance landscape for zooplankton prey capture using suction feeding. We then used the landscape to test whether a population of Chromis viridis, a coral reef zooplanktivore, is located on a performance peak or ridge based on measurements of kinematic variables recorded in-situ during undisturbed foraging. Observed trait combinations in the wild population closely matched regions of high feeding performance in the landscape, however the population was not located on a local performance peak. This sub-optimal performance was not due to constraints stemming from the observed trait correlations. The predominant directions of variation of the phenotypic traits was tangent to the ‘path of steepest ascent’ that points towards the local peak, indicating that the population does not reside on a “performance ridge”. Rather, our analysis suggests that feeding performance is constrained by stabilizing selection, possibly reflecting a balance between selection on feeding performance and mechanical or genetic constraints.

scholarly journals Feeding behaviour in a ‘basal’ tortoise provides insights on the transitional feeding mode at the dawn of modern land turtle evolution

2015 ◽  
Author(s):  
Nikolay Natchev ◽  
Nikolay Tzankov ◽  
Ingmar Werneburg ◽  
Egon Heiss
Keyword(s):  
Feeding Behaviour ◽  
Phylogenetic Position ◽  
Feeding Mode ◽  
Evolutionary Transitions ◽  
Food Items ◽  
Terrestrial Habitats ◽  
Terrestrial Environments ◽  
Food Transport ◽  
Almost All ◽  
Feeding Systems

Almost all extant land turtles are highly associated with terrestrial habitats and the few tortoises with high affinity to aquatic environment are found within the genus Manouria. Manouria belongs to a clade which forms the sister taxon to all remaining tortoises and is suitable to be used as a model for studying evolutionary transitions from water to land within modern turtles. We analysed the feeding behaviour of M. emys and due to its phylogenetic position, we hypothesise that the species might have retained some ancestral characteristics associated to aquatic lifestyle. We tested whether M. emys is able to feed both in aquatic and terrestrial environments as mud turtles do. In fact, M. emys repetitively tried to reach submerged food items in water, but always failed to grasp them and no suction feeding mechanism was applied. When feeding on land, M. emys showed another peculiar behaviour; it grasped food items by its jaws – a behaviour typical for aquatic or semiaquatic turtles – and not by the tongue as in the typical feeding mode in all tortoises studied so far. In M. emys, the hyolingual complex remained retracted during all food uptake sequences, but the food transport was entirely lingual based. The kinematical profile significantly differed from those described for other tortoises and from those proposed from the general models on the function of the feeding systems in lower tetrapods. We conclude that the feeding behaviour of M. emys might reflect a remnant of the primordial condition expected in the aquatic ancestor of tortoises.

scholarly journals Feeding behaviour in a ‘basal’ tortoise provides insights on the transitional feeding mode at the dawn of modern land turtle evolution

2015 ◽  
Author(s):  
Nikolay Natchev ◽  
Nikolay Tzankov ◽  
Ingmar Werneburg ◽  
Egon Heiss
Keyword(s):  
Feeding Behaviour ◽  
Phylogenetic Position ◽  
Feeding Mode ◽  
Evolutionary Transitions ◽  
Food Items ◽  
Terrestrial Habitats ◽  
Terrestrial Environments ◽  
Food Transport ◽  
Almost All ◽  
Feeding Systems

Almost all extant land turtles are highly associated with terrestrial habitats and the few tortoises with high affinity to aquatic environment are found within the genus Manouria. Manouria belongs to a clade which forms the sister taxon to all remaining tortoises and is suitable to be used as a model for studying evolutionary transitions from water to land within modern turtles. We analysed the feeding behaviour of M. emys and due to its phylogenetic position, we hypothesise that the species might have retained some ancestral characteristics associated to aquatic lifestyle. We tested whether M. emys is able to feed both in aquatic and terrestrial environments as mud turtles do. In fact, M. emys repetitively tried to reach submerged food items in water, but always failed to grasp them and no suction feeding mechanism was applied. When feeding on land, M. emys showed another peculiar behaviour; it grasped food items by its jaws – a behaviour typical for aquatic or semiaquatic turtles – and not by the tongue as in the typical feeding mode in all tortoises studied so far. In M. emys, the hyolingual complex remained retracted during all food uptake sequences, but the food transport was entirely lingual based. The kinematical profile significantly differed from those described for other tortoises and from those proposed from the general models on the function of the feeding systems in lower tetrapods. We conclude that the feeding behaviour of M. emys might reflect a remnant of the primordial condition expected in the aquatic ancestor of tortoises.

scholarly journals Suction Flows Generated by the Carnivorous Bladderwort Utricularia—Comparing Experiments with Mechanical and Mathematical Models

Fluids ◽  
2020 ◽  
Vol 5 (1) ◽  
pp. 33 ◽  
Author(s):  
Krizma Singh ◽  
Roberto C. Reyes ◽  
Gabriel Campa ◽  
Matthew D. Brown ◽  
Fatima Hidalgo ◽  
...  
Keyword(s):  
Solid Mechanics ◽  
Larval Fish ◽  
Fish Larvae ◽  
Experimental Studies ◽  
Axial Flow ◽  
Aquatic Organisms ◽  
Suction Feeding ◽  
Scaled Model ◽  
Feeding Mode ◽  
Biological Studies

Suction feeding is a well-understood feeding mode among macroscopic aquatic organisms. The little we know about small suction feeders from larval fish suggests that small suction feeders are not effective. Yet bladderworts, an aquatic carnivorous plant with microscopic underwater traps, have strong suction performances despite having the same mouth size as that of fish larvae. Previous experimental studies of bladderwort suction feeding have focused on the solid mechanics of the trap door’s opening mechanism rather than the mechanics of fluid flow. As flows are difficult to study in small suction feeders due to their small size and brief event durations, we combine flow visualization on bladderwort traps with measurements on a mechanical, dynamically scaled model of a suction feeder. We find that bladderwort traps generate flows that are more similar to the inertia-dominated flows of adult fish than the viscosity-dominated flows of larval fish. Our data further suggest that axial flow transects through suction flow fields, often used in biological studies to characterize suction flows, are less diagnostic of the relative contribution of inertia versus viscosity than transverse transects.

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