Replicated ecological landscapes and the evolution of morphological diversity among Gasterosteus populations from an archipelago on the west coast of Canada

2006 ◽  
Vol 84 (5) ◽  
pp. 643-654 ◽  
Author(s):  
T.E. Reimchen ◽  
P. Nosil
Keyword(s):  
Gasterosteus Aculeatus ◽  
Morphological Variability ◽  
Principal Component ◽  
Morphological Diversity ◽  
Sexually Dimorphic ◽  
Haida Gwaii ◽  
Body Depth ◽  
Eye Diameter ◽  
Freshwater Stickleback ◽  
Gill Raker

We investigated defence and trophic morphology of 40 freshwater stickleback (Gasterosteus aculeatus L., 1758) populations from the Banks–Estevan archipelago for comparison with the isolated stickleback populations from the nearby Haida Gwaii archipelago. Using 14 size-standardized metric traits and 11 meristic or categorical traits from 1706 individuals (14–54/site), we found that the first principal component (PC1) defined a defence apparatus characterized by high loadings for pelvic spine length, number of forks on the ascending process, number of lateral plates, and overlap between lateral and basal plates. The second component (PC2) defined a trophic apparatus characterized by high loadings for gape length, eye diameter, and body depth. Populations with loss of spines, loss of plates, increased gape, increased body depth, and low gill raker number were most prevalent in ponds and shallow lakes with low conductivity. Most traits were sexually dimorphic, with males exhibiting greater armature and increased benthic trophic adaptations. We observed substantially less morphological variability among Banks–Estevan stickleback populations than among the Haida Gwaii populations and one instance of common ancestry or convergence to the giant black stickleback of Haida Gwaii.

Postglacial evolution in lateral plate morphs in Norwegian freshwater populations of the threespine stickleback (Gasterosteus aculeatus)

1995 ◽  
Vol 73 (5) ◽  
pp. 898-906 ◽  
Author(s):  
Tom Klepaker
Keyword(s):  
Gasterosteus Aculeatus ◽  
Alternative Hypothesis ◽  
Morphological Variability ◽  
Threespine Stickleback ◽  
Evolutionary Stage ◽  
Lateral Plate ◽  
Land Uplift ◽  
Founding Population ◽  
Freshwater Stickleback ◽  
Age Range

Norwegian freshwater stickleback populations were founded after the last glacial period, and the progressive uplift of the land has produced an age range (1000 – 13 000 years) of the stickleback habitats. Most of the freshwater populations of today have probably been formed by isolation of marine sticklebacks in the process of land uplift. The freshwater threespine stickleback is known for its great morphological variability. Three distinct morphs ("low," "partial," and "complete") are recognized on the basis of variation in the lateral row of plates. Among the Norwegian populations, all three morphs were found, but the low morph was by far the most common and occurred mostly in monomorphic populations. The presence of the complete and partial morphs was mostly restricted to young lakes near the sea. It is likely that the plate polymorphism in this region is a transitionary evolutionary stage from a founding population dominated by complete to a monomorphic low population. The hypothesis of a polytypic origin of the low morph is discussed, and an alternative hypothesis is proposed. Within each plate morph, the number of plates also varied, and populations with exceptionally low plate numbers were mostly confined to three different areas. Within these areas, populations with plateless specimens also occurred. These plateless specimens tended to inhabit old lakes. The low plate number and plateless populations were found in parts of Norway that were deglaciated early. The advanced plate reduction can therefore be a result of a longer period of isolation and freshwater evolution. Other populations may be on their way towards extreme plate reduction, but have not yet reached the level of platelessness.

Spatial, sexual, and rapid temporal differentiation in neuromast expression on lateral plates of Haida Gwaii threespine stickleback (Gasterosteus aculeatus)

2019 ◽  
Vol 97 (11) ◽  
pp. 988-996 ◽  
Author(s):  
N.P. Planidin ◽  
T.E. Reimchen
Keyword(s):  
Gasterosteus Aculeatus ◽  
Sensory Modality ◽  
Threespine Stickleback ◽  
Predatory Fish ◽  
Limited Attention ◽  
Sexually Dimorphic ◽  
Haida Gwaii ◽  
Temporal Differentiation ◽  
Lateral Lines ◽  
Lateral Plates

Lateral lines, a major sensory modality in fishes, are diverse among taxa, but their intraspecific variation has received limited attention. We examined numbers of superficial neuromasts on the buttressing lateral plates (LP) of 1910 threespine stickleback (Gasterosteus aculeatus Linnaeus, 1758) from 26 ecologically and morphologically diverse populations on the Haida Gwaii archipelago, western Canada. Extending from previous studies, we predicted that (i) highly stained dystrophic localities would have threespine stickleback with elevated numbers of neuromasts per plate due to a greater reliance on non-visual sensory modalities and (ii) that LP count and neuromast numbers per plate would functionally covary with predatory assemblage. We found that there were no differences in neuromast count across major habitats (marine, lake, stream), but clear-water populations and those with predatory fish had significantly more neuromasts per plate than most populations in highly stained dystrophic lakes, the effects being accentuated on the first buttressing plate (LP4). We also report the first evidence that neuromast counts per plate are sexually dimorphic, with males having a greater density of neuromasts in most populations. Two transplant experiments between ecologically opposite habitats indicate that within 12 generations, neuromast counts per plate can rapidly shift in response to a change in habitat.

Silurichthys ligneolus, a new catfish (Teleostei: Siluridae) from southern Borneo, Indonesia

Zootaxa ◽  
2011 ◽  
Vol 2793 (1) ◽  
pp. 56
Author(s):  
HEOK HEE NG ◽  
HEOK HUI TAN
Keyword(s):  
New Species ◽  
Lower Lobe ◽  
Branchial Arch ◽  
Caudal Peduncle ◽  
Body Depth ◽  
Caudal Fin ◽  
Fin Rays ◽  
Eye Diameter ◽  
Gill Raker ◽  
A New Species

Silurichthys ligneolus, a new species of silurid catfish, is described from blackwater habitats in southern Borneo. The new species can be distinguished from congeners in having a combination of: body depth at anus 9.1–11.0% SL, caudal peduncle depth 4.7–5.5% SL, eye diameter 6.7–9.8% HL, pelvic fins present, 44–45 anal-fin rays, 3–4 principal rays on the lower caudal-fin lobe, lower lobe of caudal fin indistinct, 46–48 vertebrae, one gill raker on the first branchial arch, and body uniformly brown. Based on the morphology of its caudal fin, S. ligneolus is hypothesized to be the sister taxon of S. sanguineus.

scholarly journals Morphological variation of wild peppers (Capsicum spp.) from the state of Tabasco, Mexico

2018 ◽  
pp. 115 ◽  
Author(s):  
Julio C. V.-Ventura, Efrain de la Cruz-Lazaro ◽  
Rodolfo Osorio- Osorio ◽  
Pablo Preciado- Rangel
Keyword(s):  
Morphological Variability ◽  
Principal Component ◽  
Morphological Diversity ◽  
Fruit Shape ◽  
Field Trips ◽  
Leaf Length ◽  
The State ◽  
Mean Values ◽  
Capsicum Spp ◽  
Branch Density

The pepper (Capsicum spp.) is one of the most important vegetables in Mexico. The aim of this study was to collect wild peppers and characterize in situ their morphological diversity. From January to November 2015, field trips were made to 54 locations in 15 municipalities in the state of Tabasco, Mexico; 131 collections were obtained in which a total of 23 plant, flower and fruit variables were evaluated. With the mean values of the variables, principal component (PC) and cluster analyses were performed. The first three PCs explained 65.2% of total morphological variability, with the variables fruit length, fruit shape, fruit width, leaf width, leaf length, plant height and branch density providing a greater explanation for the diversity. Cluster analysis grouped the 131 collections into two groups, one formed by the morphotypes 'Amashito', 'Garbanzo' and 'Ojo de cangrejo', with characteristics of C. annuum var. Glabriusculum, and the second group with the morphotype 'Pico de paloma' with characteristics of the species C. frutescens L. It is concluded that the wild peppers of the State of Tabasco have morphological diversity, which must be preserved as a genetic resource of interest.

scholarly journals Rapid and objective characterization of channel morphology in a small, forested stream

2020 ◽  
Author(s):  
Carina Helm ◽  
Marwan A. Hassan ◽  
David Reid
Keyword(s):  
Spatial Scale ◽  
Forest Canopy ◽  
Morphological Variability ◽  
Principal Component ◽  
Morphological Diversity ◽  
Channel Morphology ◽  
Classification Rate ◽  
Cross Sectional ◽  
Small Width ◽  
Gravel Bed Streams

Abstract. Forested, gravel bed streams possess complex channel morphologies which are difficult to objectively characterise. The spatial scale necessary to adequately capture variability in these streams is often unclear, as channels are governed by irregularly spaced features and episodic processes. This issue is compounded by the high cost and time-consuming nature of field surveys in this type of environment. In larger stream systems, remotely piloted aircraft (RPAs) have proven to be effective tools for characterizing channels at high resolutions over large spatial extents, but to date their use in small, forested streams with closed forest canopies has been limited. This paper seeks to demonstrate an objective method for characterizing channel attributes over large areas, using easily extractable data from RPA imagery collected under the forest canopy in a small (width = 10 to 15 m) stream, and to provide information on the spatial scale necessary to capture the dominant spatial morphological variability of these channels. First, the accuracy and coverage of RPAs for extracting channel data was investigated through a sub-canopy survey. From this survey data, relevant cross-sectional variables were extracted and used to characterize channel unit morphology using a principal component analysis-clustering (PCA-clustering) technique. Finally, the length scale required to capture dominant morphological variability was investigated from analysis of morphological diversity along nearly 3 km of channel. The results demonstrate that sub-canopy RPA surveys provide a viable alternative to traditional survey approaches for characterizing these systems, with 87 % coverage of the main channel stream bed. The PCA-clustering analysis provided a more objective means of classifying channel morphology with a correct classification rate of 85 %. Analysis of morphological diversity suggests that reaches of at least 15 bankfull width equivalents are required to capture the channel's dominant heterogeneity. Altogether, the results provide a precedent for using RPAs to characterize the morphology and diversity of forested streams under dense canopies.

scholarly journals Morphological Diversity and Bioactive Compounds in Wall Rocket (Diplotaxis erucoides (L.) DC.)

Agronomy ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 306 ◽  
Author(s):  
Carla Guijarro-Real ◽  
Jaime Prohens ◽  
Adrián Rodríguez-Burruezo ◽  
Ana Fita
Keyword(s):  
Growth Habit ◽  
Total Phenolics ◽  
Morphological Variability ◽  
Principal Component ◽  
Morphological Diversity ◽  
Breeding Programs ◽  
New Information ◽  
Diplotaxis Erucoides ◽  
Positive Correlations ◽  
Selection Of

Wall rocket is a wild vegetable with interest to become a crop. However, the information regarding morphological variability in the species is scarce, despite the interest it has received for breeding programs. In addition, evaluating the phytochemical composition can also be useful for developing materials of a high quality. In this study, forty-four populations were evaluated for selected morphoagronomic traits and contents in ascorbic acid (AA), total phenolics (TP), and nitrates (NO3−). Wall rocket plants had, on average, an intermediate growth habit and a good response to transplant. Moderate variability, mainly for size-related traits, was found, with low to moderate heritability estimates (H2 < 0.35). A Principal Component Analysis revealed that some materials may be selected for differenced traits. On the other hand, wall rocket materials had, on average, high contents in AA (53 mg 100 g−1) and TP (116 mg CAE 100 g−1) but also accumulated high levels of NO3− (891 mg 100 g−1). Significant positive correlations were found for AA and TP, which could be exploited for increasing the antioxidant activity and properties of the final product. We provide new information on the variation of wall rocket for traits of morphological and phytochemical interest, which together with other traits, such as the profile of glucosinolates, can be useful for the selection of materials in future breeding programs.

The evolution of freshwater diversity in the threespine stickleback (Gasterosteus aculeatus): site-specific differentiation of trophic morphology

1985 ◽  
Vol 63 (11) ◽  
pp. 2632-2638 ◽  
Author(s):  
P. A. Lavin ◽  
J. D. Mcphail
Keyword(s):  
Gasterosteus Aculeatus ◽  
Morphological Variability ◽  
River System ◽  
Predatory Fish ◽  
Lateral Plate ◽  
Piscivorous Fish ◽  
Trophic Morphology ◽  
Interpopulation Variability ◽  
Gill Raker ◽  
Lateral Plates

To assess interpopulation levels of morphological variability populations of Gasterosteus aculeatus were sampled from lakes within the upper Cowichan River system (Vancouver Island, British Columbia). Phenotypic divergence between populations is assumed to be a postglacial event. Nine characters were scored; eight were related to feeding and the ninth character was lateral plate number. All populations were the low plate morph; however, populations of Gasterosteus in lakes lacking piscivorous fish had significantly fewer lateral plates than populations in lakes with predatory fish species. Two distinct trophic "morphotypes" were identified, each one associated with a specific lake environment. Populations inhabiting benthic-dominated environments were found to possess reduced gill raker number and reduced gill raker length but increased upper jaw length relative to populations from limnetic environments. We propose that the interpopulation variability in trophic morphology is a response to trophic resource differences between lakes.

Loon abundance and behaviour over four decades at a remote ecological reserve on Haida Gwaii, British Columbia, Canada

2021 ◽  
Vol 135 (1) ◽  
pp. 28-38
Author(s):  
Thomas Reimchen ◽  
Sheila Douglas
Keyword(s):  
British Columbia ◽  
Gasterosteus Aculeatus ◽  
Evolutionary Ecology ◽  
Inverse Correlation ◽  
Gavia Immer ◽  
Haida Gwaii ◽  
Average Wind Speed ◽  
The North ◽  
Common Loons ◽  
Ecological Reserve

Early studies (1976–1982) of the Drizzle Lake Ecological Reserve on Haida Gwaii, British Columbia focussed on the endemic Giant Threespine Stickleback (Gasterosteus aculeatus) and their predators. These surveys showed daily visits to the small lake (110 ha) by up to 59 adult non-breeding Common Loon (Gavia immer), an important stickleback predator and up to 19 breeding and non-breeding adult Red-throated Loon (Gavia stellata), which leave daily to forage in nearby marine waters. We continued loon surveys for 17 additional years (1983–1989, 2011–2020) and found that aggregations of non-breeding Common Loons occurred annually on the lake during July with maximum daily numbers of 78–83 individuals in 1987, 2018, and 2020 and a large increase from 2011 to 2020. We did not detect any relationship of these differences with the Pacific Decadal Oscillation but a significant inverse correlation with average wind speed. Average yearly numbers of Red-throated Loons declined by 50% from 1976 to 1989 and have remained low, with lowest numbers (<2) occurring in 2017. Two Red-throated Loon nesting territories on the lake were occupied from 1976 to 1995, with chicks occurring in 24 of 36 nests, but no successful nesting was observed on the lake over the last decade. The relative decline of Red-throated Loon in this reserve is similar to that reported in Arctic and Subarctic surveys of the species in the north Pacific and northern Europe. We discuss the implications for the evolutionary ecology of the sticklebacks and the conservation of the ecological reserve.

Species delimitation and population structure in three Onosma (Boraginaceae) species

Biologia ◽  
2015 ◽  
Vol 70 (10) ◽  
Author(s):  
Masoud Sheidai ◽  
Samira Sadeghi ◽  
Mahnaz-Arab Ameri ◽  
Ahmad-Reza Mehrabeian
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Species Delimitation ◽  
Genetic Difference ◽  
Morphological Variability ◽  
Morphological Diversity ◽  
Mantel Test ◽  
Geographical Distance ◽  
Nj Tree ◽  
Issr Molecular Markers

AbstractThe present study aimed to reveal genetic diversity and population structure in three Onosma species i.e., Onosma bulbotrichum DC., O. elwendicum Wettst. and O. sericeum Willd. (Boraginaceae) growing in Iran. This study was performed to check if the ISSR molecular markers could be used in the Onosma species delimitation. We also investigated the infra-specific morphological variability and if we can identify infra-species taxonomic forms. The present study revealed within species genetic and morphological diversity. ISSR data could delimit the studied species as they were separated from each other in NJ tree, maximum parsimony and STRUCTURE analysis. AMOVA and Hickory tests produced significant genetic difference among the studied species. The Mantel test showed no correlation between genetic distance and geographical distance of the populations for all three species. Reticulation analysis and Nm estimation showed gene flow among these populations. We could identify a few ISSR loci that are adaptive. Data obtained can be used in conservation of these medicinal plants in Iran.

scholarly journals Principal component analysis for evaluating a ranking method used in the performance testing in sheep of Morada Nova breed

2015 ◽  
Vol 36 (6) ◽  
pp. 3909
Author(s):  
Michelle Santos da Silva ◽  
Luciana Shiotsuki ◽  
Raimundo Nonato Braga Lôbo ◽  
Olivardo Facó
Keyword(s):  
Principal Component Analysis ◽  
Principal Components ◽  
Correlation Coefficients ◽  
Performance Testing ◽  
Principal Component ◽  
Component Analysis ◽  
Ranking Method ◽  
Daily Weight Gain ◽  
Meat Production ◽  
Body Depth

A multivariate approach was adopted to evaluate the relationship among traits measured in the performance testing of Morada Nova sheep, verify the efficiency of a ranking method used in these tests and identify the most significant traits for use in future analyses. Data from 150 young rams participating in five versions of the performance tests for the Morada Nova breed were used. Twenty traits were measured in each animal: initial weight (IW), final weight (FW), average daily weight gain (ADG), loin eye area (LEA), scrotal circumference (SC), fat thickness (FT), conformation (C), precocity (Pc), muscularity (M), breed features (BF), legs (L), withers height (WH), chest width (CW), rump height (RH), rump width (RW), rump length (RL), body length (BL), body depth (BD), heart girth (HG) and body condition scoring (BCS). The Pearson’s correlation coefficients ranged from –0.10 to 0.93, with the highest correlations were between body weight variables and morphometric measurements. The three first principal components explained 72.28% of the total variability among all traits. The variables related to animal size defined the first principal component, whereas those related to visual appraisal and suitability for meat production defined the second and third principal components, respectively. The combination of traits from the principal component analysis showed that the ranking method currently used in the performance testing of Morada Nova sheep is efficient for selecting larger rams with better breed features and higher degrees of specialization for meat production.

Sign in / Sign up

Export Citation Format

Share Document