Particle shape affects selection by the appendicularian <i>Oikopleura dioica</i>.

<p>Selectivity coefficients (mean Chesson’s α-index ± SE) for different bead types in the houses and guts from each of three incubation experiments with <i>Oikopleura dioica</i>. * indicates selectivity values that were significantly different from non-selectivity (α = 0.33, dashed line) tested using t-tests with a Bonnferoni correction of alpha level (p ≤ 0.0028) (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0183105#pone.0183105.t003" target="_blank">Table 3</a>).</p

Jet wakes of W. cylindrica from Hydrodynamic advantages of swimming by salp chains

Jet wakes of a W. cylindrica aggregate visualized using fluorescein dye

Experimental conditions for three incubation experiments.

<p>Experimental conditions for three incubation experiments.</p

W. cylinidrca solitary from Hydrodynamic advantages of swimming by salp chains

In situ swimming of W. cylinidrca solitary showing unsteady locomotion

W. cylinidrca aggregate from Hydrodynamic advantages of swimming by salp chains

In situ swimming of W. cylinidrca aggregate showing steady locomotion

Experimental bead mixture for incubations.

<p>(A) Schematic of experimental bead mixture used in each of three incubation experiments with <i>Oikopleura dioica</i>. (B) Top: <i>O</i>. <i>dioica</i> in house filtering a mixture of <i>Rhinomonas reticulata</i> (red, ~17 μm diameter) and fluorescent 10 μm microspheres (green). PF: pharyngeal filter; FCF: food-concentrating filter. Scale bar 0.5 mm. Bottom: experimental bead mixture (3–10 μm) in the gut post-incubation. Scale bar 50 μm.</p

Fate of different shaped beads from three incubation experiments.

<p>Relative proportions (mean ± SD) of various bead mixes in the ambient water at the start of the incubation (T₀), gut, and house of the appendicularian <i>Oikopleura dioica</i>.</p

Morphologically diverse marine microbes.

<p>Length-to-width ratio versus surface-equivalent sphere diameter (ESD) [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0183105#pone.0183105.ref013" target="_blank">13</a>] of some abundant free-living microbes in the upper ocean (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0183105#pone.0183105.s001" target="_blank">S1 Table</a>). Surface area (<i>S</i>) of ESD () was calculated based on the assumption of a prolate spheroid [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0183105#pone.0183105.ref013" target="_blank">13</a>]. Color of points shows average abundances. Dashed black line represents the length: width ratio of a perfectly spherical cell.</p

Trajectories and orientation of spheroidal microbeads through the feeding-filter of <i>Oikopleura dioica</i>.

<p>(A) Frequency histograms show the angles for prolate spheroid microbeads (7.8 x 22 μm) suspended in the fluid of the food-concentrating filter and adhered to the filter mesh of <i>Oikopleura dioica</i>. Sectors correspond to number of beads observed, Ф is the grand mean direction for all beads, <i>N</i> is the number of independently measured beads, <i>n</i> is the instantaneous angles pooled for all beads. Angle measurements for beads adhered to the mesh represent independent measurements for <i>N</i> = 40 beads, whereas measurements for beads suspended in the fluid represent instantaneous angles pooled for all individuals, <i>n</i> = 192, from the trajectories of <i>N</i> = 10 beads. All angles are relative to the fluid flow. (B) Five sample trajectories of beads transported through the food-concentrating filter (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0183105#pone.0183105.s002" target="_blank">S1 Video</a>). Frames were colored-coded (red, yellow, green, cyan, blue, magenta) so that the color order shows direction and white indicates a particle has not moved. Arrows show directions of fluid flow. Montages show the bead orientations for the respective trajectory.</p

Statistical results for incubation experiments.

<p>Statistical results for incubation experiments.</p