Stairway to Heaven: Evaluating Levels of Biological Organization Correlated with the Successful Ascent of Natural Waterfalls in the Hawaiian Stream Goby Sicyopterus stimpsoni

Selective pressures generated by locomotor challenges act at the level of the individual. However, phenotypic variation among individuals that might convey a selective advantage may occur across any of multiple levels ofbiological organization. In this study, we test for differences in external morphology, muscle mechanical advantage, muscle fiber type and protein expression among individuals of the waterfall climbing Hawaiian fish Sicyopterus stimpsoni collected from sequential pools increasing in elevation within a single freshwater stream. Despite predictions from previous laboratory studies of morphological selection, few directional morphometric changes inbody shape were observed at successively higher elevations. Similarly, lever arm ratios associated with the main pelvic sucker, central to climbing ability in this species, did not differ between elevations. However, among climbingmuscles, the adductor pelvicus complex (largely responsible for generating pelvic suction during climbing) contained a significantly greater red muscle fiber content at upstream sites. A proteomic analysis of the adductor pelvicusrevealed two-fold increases in expression levels for two respiratory chain proteins (NADH:ubiquinone reductase and cytochrome b) that are essential for aerobic respiration among individuals from successively higher elevations.Assessed collectively, these evaluations reveal phenotypic differences at some, but not all levels of biological organization that are likely the result of selective pressures experienced during climbing

Code and data files for Lambert et al., "Optimizing Invader Suppression to Restore Native Species: Leveraging Species Traits to Overcome Collateral Damage", Journal of Applied Ecology (2023)

Code and data associated with the manuscript: Lambert, T. D., McIntyre, P. B., Moody, K. N., and Ellner, S. P. (2023). "Optimizing Invader Suppression to Restore Native Species: Leveraging Species Traits to Overcome Collateral Damage", Journal of Applied Ecology.</p

Stairway to Heaven: Evaluating Levels of Biological Organization Correlated with the Successful Ascent of Natural Waterfalls in the Hawaiian Stream Goby <i>Sicyopterus stimpsoni</i>

<div><p>Selective pressures generated by locomotor challenges act at the level of the individual. However, phenotypic variation among individuals that might convey a selective advantage may occur across any of multiple levels of biological organization. In this study, we test for differences in external morphology, muscle mechanical advantage, muscle fiber type and protein expression among individuals of the waterfall climbing Hawaiian fish <i>Sicyopterus stimpsoni</i> collected from sequential pools increasing in elevation within a single freshwater stream. Despite predictions from previous laboratory studies of morphological selection, few directional morphometric changes in body shape were observed at successively higher elevations. Similarly, lever arm ratios associated with the main pelvic sucker, central to climbing ability in this species, did not differ between elevations. However, among climbing muscles, the adductor pelvicus complex (largely responsible for generating pelvic suction during climbing) contained a significantly greater red muscle fiber content at upstream sites. A proteomic analysis of the adductor pelvicus revealed two-fold increases in expression levels for two respiratory chain proteins (NADH:ubiquinone reductase and cytochrome b) that are essential for aerobic respiration among individuals from successively higher elevations. Assessed collectively, these evaluations reveal phenotypic differences at some, but not all levels of biological organization that are likely the result of selective pressures experienced during climbing.</p> </div

SicyopterusStimpsoniMorphologyData

Morphological data for each individua

SicyopterusStimpsoniMicrosatelliteData

Microsatellite allelic data for each individual

SicyopterusStimpsoniSamplingSiteInfo

SicyopterusStimpsoniSamplingSiteInf

JMPScriptsforMorphology

JMPScriptsforMorpholog

Muscles assessed for effects of climbing selection.

<p>(A) Schematic drawing of <i>Sicyopterus stimpsoni</i> (upper left) and the area of dissection (box and enlargement). Muscles and their respective in- and out-levers are indicated in the magnified drawings of the pelvic girdle (B, C). The relative position of the adductor pectoralis is indicated by the arrow near the top of the drawing. The position of the abductor pelvicus complex deep to the pelvis is indicated by the hashed line in C. Muscles for which red fiber content was established are in bold print. Drawing not to scale.</p