Biology subjects

Scott, R. J.

Publications and source records attributed to Scott, R. J..

4 recordsLinked to original sources

bioRxiv2022

Population variation in lipid depletion during parental care in male threespine sticklebacks (Gasterosteus aculeatus).

I examined changes in stored lipid over the parental care interval in several populations of threespine stickleback (Gasterosteus aculeatus). Males from the limnetic populations and the marine population decreased in stored lipids over the progression of the nesting interval. Of the two benthic populations, one (Hotel Lake) did not decrease stored lipids over the parental care interval, as predicted, whereas the other (Crystal Lake) showed declining stored lipids over the parental care interval. Though food resources are likely high in the nesting area of Crystal Lake, the high density of conspecific cannibal groups in the littoral zone likely contributes to reduced foraging and elevated guarding/diversionary display behaviour and dependency on stored lipids to fuel those behaviours in the Crystal Lake (benthic) population. This study demonstrates the value of considering different ecological conditions on behavioural and energetic constraints among populations of threespine stickleback.

ecology↗

bioRxiv2022

Armor reduction and pelvic girdle loss in a population of threespine stickleback (Gasterosteus aculeatus) from western Newfoundland, Canada.

We describe the antipredator armor of a unique population of threespine stickleback (Gasterosteus aculeatus) from Narrows Pond in western Newfoundland and compare traits for this population to nearby populations from marine and freshwater systems. After standardizing for length, Narrows Pond stickleback are shallower bodied and have shorter dorsal spines than stickleback from the other populations. Also, though the number of armor plates for Narrows Pond stickleback is greater than for typical low-plate morphs, the size of the lateral plates for Narrows Pond stickleback is much smaller. Finally, most (nearly 75% of sampled individuals) Narrows Pond stickleback do not have a pelvic structure (bilateral pelvic plate, ascending process, and ventral spine) and the remaining individuals have greatly reduced pelvic girdle whereas all individuals from the other populations possessed complete pelvic structures.

evolutionary biology↗

bioRxiv2022

Variation in morphology among populations of threespine stickleback (Gasterosteus aculeatus) from western Newfoundland, Canada.

Freshwater populations of threespine stickleback (Gasterosteus aculeatus) have diverged from their marine ancestor and show extensive variation among populations throughout most of their range. However, phenotypes of freshwater populations from the east coast of North America does not appear to demonstrate extensive variability observed throughout the rest of the species range. The relative young age of east coast North American populations may explain the apparent lack of freshwater variability. On the other hand, populations in this part of the species range have not received the level of attention as have populations throughout the rest of its range and the low level of variability observed may simply reflect lack of data for this region. We examined morphological traits (including linear measurements of body armor and body shape) of stickleback from 52 locations representing marine and freshwater populations along the west coast of Newfoundland, Canada. We found that variability in morphological traits among freshwater populations was much more extensive than previously assumed and similar to patterns observed throughout the rest of the species range.

evolutionary biology↗

bioRxiv2022

Plasticity of threespine stickleback nuptial signals: laboratory manipulation of ambient light causes a shift in male reflectance patterns.

I caught courting male threespine stickleback (Gasterosteus aculeatus) in Hotel Lake, BC, Canada, and transferred them to one of three experimental lighting environments. Male signal reflectance was measured upon capture from the lake, at one-day post transfer to the experimental light, and at onset of courtship behaviour under artificial light. Male signals responded rapidly to the change in lighting environment following transfer from the wild to the artificial lighting environments and in different ways dependent upon the artificial light composition. Males under red-shifted light had higher signal reflectance in the short wavelength range of the spectrum and less reflectance in the medium and long wavelength range of the spectrum relative to the males in blue-green shifted and full-spectrum lighting. Given the relative prominence of the male stickleback nuptial signal in the behavioural ecology literature, the increasing evidence for the signals ambient light dependent expression, and the large body of literature based on experiments conducted under artificial light, it would be prudent to repeat some of the classic mate choice experiments under more realistic lighting conditions.

animal behavior and cognition↗