Reprint of "Pleistocene and Holocene glacier fluctuations upon the Kamchatka Peninsula"

Journal of Fish Biology

Бочарова

Mugue

et al. 2017

Six postglacial lakes were studied along both sides of the Kamchatka central mountain range, Russia. Pairs of local morphotypes of species of Arctic charrs, Salvelinus spp., have previously been described from the southernmost lakes while the fish fauna of the four northernmost lakes was studied here for the first time. Phenotypic data support the division of Kamchatkan lacustrine charrs into two groups according to the number of gill rakers and pyloric caeca, as well as snout-dorsal and snout-ventral distances (MANOVA, P < 0·001). These groups respectively correspond to phenotypes commonly referred to as Salvelinus malma and Salvelinus taranetzi. To clarify the identity of these groups, D-loop and cytochrome b (cytb) region sequences were analysed. Haplotype network analysis of mtDNA shows the salmonids inhabiting four lakes on the south and north are phylogenetically close to either Beringian S. malma or to S. taranetzi from the Chukotka and Kolyma River basins (the mean ± s.e. pairwise per cent sequence divergence is 0·006 ± 0·001). Phenotype-genotype discordance suggests that mitochondrial introgression between species has occurred in the two smallest lakes (<0·5 km ) in the central part of the peninsula. Identical haplotypes of D-loop and cytb regions were found for the populations of S. taranetzi from the most distant southern and northern lakes, indicating all lakes were colonized by both species simultaneously after the last glacial maximum. Salvelinus taranetzi may have colonized the Kamchatka peninsula from one or both of two different source regions: the Arctic Beringia and the northern coast of the Okhotsk Sea.

Section: Discussionmentioning

confidence: 94%

Occurrence of sympatric charr groups, Salvelinus, Salmonidae, in the lakes of Kamchatka: a legacy of the last glaciations

Journal of Fish Biology

Бочарова

Mugue

et al. 2017

“…Following the traditional view on adaptive radiation as the result of food resource partitioning (Bolnick & Fitzpatrick, 2007; Nosil, 2012; Robinson & Wilson, 1994; Via, 2009), we propose the following scenario of the Kamchatka River charr divergence. During the Pleistocene, when spruce forests began to occupy the broad areas of the Kamchatka River basin (Barr & Solomina, 2015; Klimaschewski et al., 2015), S. malma formed the non‐anadromous groups differing in the diet: benthos or fish food. Both groups underwent the pressure of conifer litter influence during the reproduction.…”

Section: Discussionmentioning

confidence: 99%

“…In order to ascertain external and internal factors driving riverine adaptive radiation, we studied the ‘flock’ of charrs (Salmonidae) dwelling in the Kamchatka River. This basin is one of the most ancient and largest water net of the North Pacific, which was not glaciated during the late Pleistocene (Barr & Solomina, 2015; Chereshnev, 1998; Elias & Brigham‐Grette, 2013). In the absence of glaciers, the Kamchatka River acted as a refugium providing for a diversity burst in the lineage of the charr Salvelinus malma (Brunner et al., 2001; Oleinik et al., 2015).…”

Section: Introductionmentioning

confidence: 99%

Natural toxic impact and thyroid signalling interplay orchestrates riverine adaptive divergence of salmonid fish

Journal of Animal Ecology

Маркевич

Melnik

et al. 2021

Adaptive radiation in fishes has been actively investigated over the last decades. Along with numerous well‐studied cases of lacustrine radiation, some examples of riverine sympatric divergence have been recently discovered. In contrast to the lakes, the riverine conditions do not provide evident stability in the ecological gradients. Consequently, external factors triggering the radiation, as well as developmental mechanisms underpinning it, remain unclear. Herein, we present the comprehensive study of external and internal drivers of the riverine adaptive divergence of the salmonid fish Salvelinus malma. In the Kamchatka River, north‐east Asia, this species splits in the reproductively isolated morphs that drastically differ in ecology and morphology: the benthivorous Dolly Varden (DV) and the piscivorous stone charr (SC). To understand why and how these morphs originated, we performed a series of field and experimental work, including common‐garden rearing, comparative ontogenetic, physiological and endocrinological analyses, hormonal ‘engineering’ of phenotypes and acute toxicological tests. We revealed that the type of spawning ground acts as the decisive factor driving the radiation of S. malma. In contrast to DV spawning in the leaf krummholz zone, SC reproduces in the zone of coniferous forest, which litter has a toxic impact on developing fishes. SC enhances resistance to the toxicants via metabolism acceleration provided by the elevated thyroid hormone expenditure. These physiological changes lead to the multiple heterochronies resulting in a specific morphology and ecology of SC. Salvelinus malma represents a notable example of how the thyroid axis contributes to the generation of diverse phenotypic outcomes underlying the riverine sympatric divergence. Our findings, along with the paleoecology data concerning spruce forest distribution during the Pleistocene, provide an opportunity to reconstruct a scenario of S. malma divergence. Taken together, obtained results with the data of the role of thyroid hormones in the ontogeny and diversification of fishes contribute a resource to consider the thyroid axis as a prime director orchestrating the phenotypic plasticity promoting evolutionary diversification under the changing environmental conditions.

“…In order to ascertain external and internal factors driving riverine adaptive radiation, we studied the 'flock' of charrs (Salmonidae) dwelling in the Kamchatka River. This basin is one of the most ancient and the largest water net of the North Pacific, which was not glaciated during the late Pleistocene (Chereshnev, 1998; Elias & Brigham-Grette, 2013; Barr & Solomina, 2015). In the absence of glaciers, the Kamchatka River acted as a refugium providing for a diversity burst in the lineage of the charr Salvelinus malma (Brunner et al, 2001;Oleinik et al, 2015).…”

Section: Introductionmentioning

confidence: 99%

“…During the Pleistocene, when spruce forests began to occupy the broad areas of the Kamchatka River basin(Barr & Solomina, 2015;Klimaschewski et al, 2015), S. malma -a species with an amazing level of developmental plasticity -underwent the pressure of conifer litter influence. The individuals characterized by the enhanced thyroid axis activity happened to obtain an advantageous position due to an enhanced resistance to the toxic environment.…”

mentioning

confidence: 99%

Natural toxic impact and thyroid signaling interplay orchestrates riverine adaptive divergence of Dolly Varden.

Маркевич²,

Melnik

et al. 2020

Preprint

Background Adaptive radiation in fishes has been actively investigated over the last decades. Along with numerous well-studied cases of lotic radiation, some examples of riverine sympatric divergence have been recently discovered. In contrast to the lakes, the riverine conditions do not provide evident stability in the ecological gradients. Consequently, external factors triggering the radiation, as well as developmental mechanisms underpinning it, remain unclear. Herein, we present the comprehensive study of external and internal drivers of the riverine adaptive divergence of the salmonid fish Salvelinus malma. In the Kamchatka River, this species splits in the reproductively isolated morphs that drastically differ in ecology and morphology: the benthivorous Dolly Varden (DV) and the piscivorous Stone charr (SC). To understand why and how these morphs originated, we performed a series of field and experimental work, including common-garden rearing, comparative ontogenetic, physiological and endocrinological analyses, hormonal "engineering" of phenotypes.Results We revealed that the type of spawning ground acts as the main external factor driving the radiation of S. malma . In contrast to DV spawning in the leaf krummholz zone, SC reproduces in the zone of coniferous forest, which litter has a toxic impact on developing fishes. SC enhances resistance to the toxicants via metabolism acceleration provided by the elevated thyroid hormone content. These physiological changes lead to the multiple heterochronies resulting in a specific morphology and SC's expansion into a piscivorous niche.Conclusions S. malma represents a notable example of how the thyroid axis contributes to the generation of diverse phenotypic outcomes underlying the riverine sympatric divergence. Our findings, along with the paleoecology data concerning spruce forest distribution during the Pleistocene, provide an opportunity to reconstruct a scenario of S. malma divergence. Taken together, obtained results with the data of the role of thyroid hormones in the ontogeny and diversification of fishes contribute a resource to consider the thyroid axis as a prime director orchestrating the phenotypic plasticity promoting evolutionary diversification under the changing environmental conditions.