Data from: Spatial sorting caused by downstream dispersal: Implication for morphological evolution in isolated populations of fat minnow inhabiting small streams flowing through terraced rice paddies

Yamada, Hiroyuki1

Published Aug 30, 2024; Updated Sep 02, 2024 on Dryad. https://doi.org/10.5061/dryad.h70rxwdtd

Abstract

The evolutionary forces arising from differential dispersal are known as “spatial sorting,” distinguishing them from natural selection arising from differential survival or differential reproductive success. Spatial sorting is often considered to be transient, because it is offset by the return of dispersers in many cases. However, in riverine systems, spatial sorting by downstream dispersal can be cumulative in habitats upstream of migration barriers such as weirs or falls, which can block the return of the dispersers. Terraced rice paddies are often found on steep mountain slopes in Japan and often incorporate small streams with numerous migration barriers. This study investigated the morphological features of fat minnow, Rhynchocypris oxycephalus jouyi (Cyprinidae), inhabiting above-barrier habitats of the small streams flowing through flood-prone terraced rice paddies and examined their function via a mark–recapture experiment. Although this study did not reveal a consistent pattern across all local populations, some above-barrier populations were characterised by individuals with a thinner caudal peduncle, thinner body, and longer ventral caudal fin lobes than those in neighbouring mainstream populations. A mark–recapture experiment during flooding showed that a thinner caudal peduncle and deeper body helped fat minnow avoid downstream dispersal and ascend a small step, and suggested that a longer ventral caudal fin lobe was important for ascending. These results suggest that the caudal morphologies of some above-barrier populations avoid or reduce the risk of downstream dispersal, supporting the idea that spatial sorting shapes functional traits, enhancing the spatial persistence of individuals in upstream habitats.

README: Spatial sorting caused by downstream dispersal: implication for morphological evolution in isolated populations of fat minnow inhabiting small streams flowing through terraced rice paddies

https://doi.org/10.5061/dryad.h70rxwdtd

Description of the data and file structure

Files and variables

File: EnvironmentalDataForInterpopulationComparison(Yamada_2024).csv

Description:

Variables

Station: Name of the survey station.
StreamWidth(m): Stream width measured at 5 m intervals from the lowest point of each station.
MeanStreamWidth(m): Mean of the "StreamWidth(m)".
SD(StreamWidth): Standard deviation of the "StreamWidth(m)".
Elevation(m): Mean elevation of the lowest and highest points at each station.
StationLength(m): The length of the station along the stream.
DeltaElevation(m): The difference in elevation between the lowest and highest points of the station.
Slope(%): Slope of the station.

Note: There is only a single value for each station in the columns other than "StreamWidth(m)". Therefore, those empty cells are filled with the symbol "-".

File: InterpopulationComparison(Yamada_2024).csv

Description:

Variables

PictureID: The ID of the measured fish image.
ForkLength(mm): Measured values of the Fork Length (mm).
DorsalCaudalFinLobeLength(mm): Measured values of the Dorsal Caudal Fin Lobe Length (mm).
VentralCaudalFinLobeLength(mm): Measured values of the Ventral Caudal Fin Lobe Length (mm).
CaudalPeduncleDepth(mm): Measured values of the Caudal Peduncle Depth (mm).
BodyDepth(mm): Measured values of the Body Depth (mm).
Habitat: Habitat category of the station.
Station: Name of the survey station.

File: MarkRecaptureExperiment(Yamada_2024).csv

Description:

Variables

PictureID: The ID of the measured fish image.
ForkLength(mm): Measured values of the Fork Length (mm).
DorsalCaudalFinLobeLength(mm): Measured values of the Dorsal Caudal Fin Lobe Length (mm).
VentralCaudalFinLobeLength(mm): Measured values of the Ventral Caudal Fin Lobe Length (mm).
CaudalPeduncleDepth(mm): Measured values of the Caudal Peduncle Depth (mm).
BodyDepth(mm): Measured values of the Body Depth (mm).
Section: Name of the section from which the fish were recaptured.
RetentionStatus: Retention status (0 = dispersed individuals; 1 = remaining individuals)
AscentStatus: Ascent status (0 = individuals that did not ascend; 1 = individuals that ascended)

Note: To avoid data bias, individuals recaptured as mortal were also photographed and measured.

Raw data (TIFF files)

The name of the TIFF files matches the information in the "PictureID" column of the CSV files (i.e., "InterpopulationComparison(Yamada_2024).csv" and "MarkRecaptureExperiment(Yamada_2024).csv").

Data from: Spatial sorting caused by downstream dispersal: Implication for morphological evolution in isolated populations of fat minnow inhabiting small streams flowing through terraced rice paddies

Data files

Abstract

README: Spatial sorting caused by downstream dispersal: implication for morphological evolution in isolated populations of fat minnow inhabiting small streams flowing through terraced rice paddies

Description of the data and file structure

Files and variables

File: EnvironmentalDataForInterpopulationComparison(Yamada_2024).csv

Variables

File: InterpopulationComparison(Yamada_2024).csv

Variables

File: MarkRecaptureExperiment(Yamada_2024).csv

Variables

Raw data (TIFF files)

Works referencing this dataset