Pub Date : 2018-05-04DOI: 10.1163/18759866-08701004
Denis Audo, M. Hyžný, S. Charbonnier
Polychelidan lobsters, as the sister group of Eureptantia (other lobsters and crabs), have a key-position within decapod crustaceans. Their evolutionary history is still poorly understood, although it has been proposed that their Mesozoic representatives largely inhabited shallow-marine environment and only later sought refuge in deep water. This view has recently been challenged, so the evolutionary history of polychelidans is in a need of re-appraisal. The earliest representatives, such as Tetrachela from the Late Triassic of Austria and Italy, are of great importance because of their potential in investigation of life habits of early polychelidans. Tetrachela lived in a relatively deep water, however, its well-developed eyes suggest an environment where light was still present. With its massive dorsoventrally flattened body plan, Tetrachela was probably benthic; the shape of its mandible and stocky first pereiopods suggest it was a scavenger and/or fed on slowly moving or sedentary animals. The carapace of Tetrachela has a peculiar groove pattern, which leads us to redefine some elements of the nomenclature of grooves used for polychelidans. Based on the present revision we propose that the second incision and its associated groove correspond to the hepatic groove, not the postcervical or the branchiocardiac grooves as interpreted previously. This revision allows us to review the homologies of cephalothoracic groove between polychelidans and other notable groups of decapod crustaceans.
{"title":"The early polychelidan lobster Tetrachela raiblana and its impact on the homology of carapace grooves in decapod crustaceans","authors":"Denis Audo, M. Hyžný, S. Charbonnier","doi":"10.1163/18759866-08701004","DOIUrl":"https://doi.org/10.1163/18759866-08701004","url":null,"abstract":"Polychelidan lobsters, as the sister group of Eureptantia (other lobsters and crabs), have a key-position within decapod crustaceans. Their evolutionary history is still poorly understood, although it has been proposed that their Mesozoic representatives largely inhabited shallow-marine environment and only later sought refuge in deep water. This view has recently been challenged, so the evolutionary history of polychelidans is in a need of re-appraisal. The earliest representatives, such as Tetrachela from the Late Triassic of Austria and Italy, are of great importance because of their potential in investigation of life habits of early polychelidans. Tetrachela lived in a relatively deep water, however, its well-developed eyes suggest an environment where light was still present. With its massive dorsoventrally flattened body plan, Tetrachela was probably benthic; the shape of its mandible and stocky first pereiopods suggest it was a scavenger and/or fed on slowly moving or sedentary animals. The carapace of Tetrachela has a peculiar groove pattern, which leads us to redefine some elements of the nomenclature of grooves used for polychelidans. Based on the present revision we propose that the second incision and its associated groove correspond to the hepatic groove, not the postcervical or the branchiocardiac grooves as interpreted previously. This revision allows us to review the homologies of cephalothoracic groove between polychelidans and other notable groups of decapod crustaceans.","PeriodicalId":55210,"journal":{"name":"Contributions to Zoology","volume":"87 1","pages":"41-57"},"PeriodicalIF":2.2,"publicationDate":"2018-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1163/18759866-08701004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45752383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-04-13DOI: 10.1163/18759866-08701003
Valentin Rineau, R. Z. Bagils, M. Laurin
Simulation-based and experimental studies are crucial to produce factual arguments to solve theoretical and methodological debates in phylogenetics. However, despite the large number of works that tested the relative efficiency of phylogenetic methods with various evolutionary models, the capacity of methods to manage various sources of error and homoplasy has almost never been studied. By applying ordered and unordered methods to datasets with iterative addition of errors in the ordering scheme, we show that unordered coding in parsimony is not a more cautious option. A second debate concerns how to handle reversals, especially when they are regarded as possible synapomorphies. By comparing analyses of reversible and irreversible characters, we show empirically that three-taxon analysis (3ta) manages reversals better than parsimony. For Brownian motion data, we highlight that 3ta is also more efficient than parsimony in managing random errors, which might result from taphonomic problems or any homoplasy generating events that do not follow the dichotomy reversal/ convergence, such as lateral gene transfer. We show parsimony to be more efficient with numerous character states (more than four), and 3ta to be more efficient with binary characters, both methods being equally efficient with four states per character. We finally compare methods using two empirical cases of known evolution.
{"title":"Impact of errors on cladistic inference: simulation-based comparison between parsimony and three-taxon analysis","authors":"Valentin Rineau, R. Z. Bagils, M. Laurin","doi":"10.1163/18759866-08701003","DOIUrl":"https://doi.org/10.1163/18759866-08701003","url":null,"abstract":"Simulation-based and experimental studies are crucial to produce factual arguments to solve theoretical and methodological debates in phylogenetics. However, despite the large number of works that tested the relative efficiency of phylogenetic methods with various evolutionary models, the capacity of methods to manage various sources of error and homoplasy has almost never been studied. By applying ordered and unordered methods to datasets with iterative addition of errors in the ordering scheme, we show that unordered coding in parsimony is not a more cautious option. A second debate concerns how to handle reversals, especially when they are regarded as possible synapomorphies. By comparing analyses of reversible and irreversible characters, we show empirically that three-taxon analysis (3ta) manages reversals better than parsimony. For Brownian motion data, we highlight that 3ta is also more efficient than parsimony in managing random errors, which might result from taphonomic problems or any homoplasy generating events that do not follow the dichotomy reversal/ convergence, such as lateral gene transfer. We show parsimony to be more efficient with numerous character states (more than four), and 3ta to be more efficient with binary characters, both methods being equally efficient with four states per character. We finally compare methods using two empirical cases of known evolution.","PeriodicalId":55210,"journal":{"name":"Contributions to Zoology","volume":"87 1","pages":"25-40"},"PeriodicalIF":2.2,"publicationDate":"2018-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1163/18759866-08701003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47754769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-03-12DOI: 10.1163/18759866-08701001
R. Croitor, T. Obada
This article reports antler remains from the Late Paleolithic site of Climăuți II (Republic of Moldova) confirming the presence of wapiti Cervus canadensis in the Late Pleistocene of Western Eurasia. The occurrence of wapiti in the East Carpathian area by 20 ky BP coincides with the local extinction of Megaloceros giganteus , Crocuta spelaea , and Ursus spelaeus , and substitution of local forest reindeer with grazing tundra-steppe Rangifer tarandus constantini . We here provide an overview of paleontological data and opinions on the presence of Cervus canadensis in Europe, a discussion on the taxonomic status and systematic position of the extinct deer Cervus elaphus palmidactyloceros , and propose a dispersal model for wapiti in Europe during the Late Pleistocene.
{"title":"On the presence of Late Pleistocene wapiti, Cervus canadensis Erxleben, 1777 (Cervidae, Mammalia) in the Palaeolithic site Climăuți II (Moldova)","authors":"R. Croitor, T. Obada","doi":"10.1163/18759866-08701001","DOIUrl":"https://doi.org/10.1163/18759866-08701001","url":null,"abstract":"This article reports antler remains from the Late Paleolithic site of Climăuți II (Republic of Moldova) confirming the presence of wapiti Cervus canadensis in the Late Pleistocene of Western Eurasia. The occurrence of wapiti in the East Carpathian area by 20 ky BP coincides with the local extinction of Megaloceros giganteus , Crocuta spelaea , and Ursus spelaeus , and substitution of local forest reindeer with grazing tundra-steppe Rangifer tarandus constantini . We here provide an overview of paleontological data and opinions on the presence of Cervus canadensis in Europe, a discussion on the taxonomic status and systematic position of the extinct deer Cervus elaphus palmidactyloceros , and propose a dispersal model for wapiti in Europe during the Late Pleistocene.","PeriodicalId":55210,"journal":{"name":"Contributions to Zoology","volume":"87 1","pages":"1-10"},"PeriodicalIF":2.2,"publicationDate":"2018-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1163/18759866-08701001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43906442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-03-12DOI: 10.1163/18759866-08701002
Diego A. Caraballo, M. S. Rossi
Subterranean rodents of the genus Ctenomys have experienced an explosive radiation and rapidly colonized the southern cone of South America. The torquatus group, one of the main groups of the genus, comprises several species and species complexes which inhabit the eastern part of the distribution of Ctenomys including southern Brazil, northern and central Uruguay and north-eastern Argentina. This group has undergone a high chromosomal diversification with diploid numbers varying from 41 to 70. The aim of this study was to investigate the origins of the torquatus group as well as its diversification patterns in relation to geography and cladogenesis. Based on mitochondrial cytochrome b nucleotide sequences we conducted a Bayesian multi-calibrated relaxed clock analysis to estimate the ages of the torquatus group and its main lineages. Using the estimated evolutionary rate we performed a continuous phylogeographic analysis, using a relaxed random walk model to reconstruct the geographic diffusion of the torquatus group in a temporal frame. The torquatus group originated during the early Pleistocene between 1.25 and 2.32 million years from the present in a region that includes the northwest of Uruguay and the southeast of the Brazilian state of Río Grande do Sul. Most lineages have dispersed early towards their present distribution areas going through subsequent range expansions in the last 800,000 – 700,000 years. Ctenomys torquatus went through a rapid range expansion for the last 200,000 years, becoming the most widespread species of the group. The colonization of the Corrientes and Entre Ríos Argentinean provinces supposes at least two crossing events across the Uruguay River between 1.0 and 0.5 million years before the present, in the context of a cold and dry paleoenvironment. The resulting temporal and geographic frame enables the comprehension of the incidence of both, the amplitude of distribution areas and divergence times into the patterns of chromosomal diversification found in the group.
{"title":"Spatial and temporal divergence of the torquatus species group of the subterranean rodent Ctenomys","authors":"Diego A. Caraballo, M. S. Rossi","doi":"10.1163/18759866-08701002","DOIUrl":"https://doi.org/10.1163/18759866-08701002","url":null,"abstract":"Subterranean rodents of the genus Ctenomys have experienced an explosive radiation and rapidly colonized the southern cone of South America. The torquatus group, one of the main groups of the genus, comprises several species and species complexes which inhabit the eastern part of the distribution of Ctenomys including southern Brazil, northern and central Uruguay and north-eastern Argentina. This group has undergone a high chromosomal diversification with diploid numbers varying from 41 to 70. The aim of this study was to investigate the origins of the torquatus group as well as its diversification patterns in relation to geography and cladogenesis. Based on mitochondrial cytochrome b nucleotide sequences we conducted a Bayesian multi-calibrated relaxed clock analysis to estimate the ages of the torquatus group and its main lineages. Using the estimated evolutionary rate we performed a continuous phylogeographic analysis, using a relaxed random walk model to reconstruct the geographic diffusion of the torquatus group in a temporal frame. The torquatus group originated during the early Pleistocene between 1.25 and 2.32 million years from the present in a region that includes the northwest of Uruguay and the southeast of the Brazilian state of Río Grande do Sul. Most lineages have dispersed early towards their present distribution areas going through subsequent range expansions in the last 800,000 – 700,000 years. Ctenomys torquatus went through a rapid range expansion for the last 200,000 years, becoming the most widespread species of the group. The colonization of the Corrientes and Entre Ríos Argentinean provinces supposes at least two crossing events across the Uruguay River between 1.0 and 0.5 million years before the present, in the context of a cold and dry paleoenvironment. The resulting temporal and geographic frame enables the comprehension of the incidence of both, the amplitude of distribution areas and divergence times into the patterns of chromosomal diversification found in the group.","PeriodicalId":55210,"journal":{"name":"Contributions to Zoology","volume":"87 1","pages":"11-24"},"PeriodicalIF":2.2,"publicationDate":"2018-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1163/18759866-08701002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44343472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-22DOI: 10.1163/18759866-08604002
S. Penny, A. Crottini, F. Andreone, A. Bellati, Lovasoa M. S. Rakotozafy, M. Holderied, C. Schwitzer, G. Rosa
Prior herpetological surveys in 1996 and 2000 identified 14 species of amphibians and 32 species of reptiles from the Sahamalaza Peninsula. This work increases the total number of amphibian and reptile species known from this area to 20 and 43 respectively. To maximise our chances of species detection, survey effort covered the entire wet season and part of the dry season, and utilised a combination of opportunistic searching, transect searching, pitfall trapping, and acoustic recording. We identified species through an integrative taxonomic approach, combining morphological, bio- acoustic and molecular taxonomy. Together, this enabled the detection of cryptic and seasonally inactive species that were missed in the shorter prior surveys that relied on morphological identification alone. The taxonomic identification of amphibians utilised a fragment of the mitochondrial 16S rRNA gene; taxonomic identi- fication of reptiles utilised a fragment of the mitochondrial COI gene, and when necessary, also mitochondrial fragments of the 16S rRNA ND1, ND2, ND4 genes. All sequences were deposited in Genbank and COI sequences were also deposited in the BOLD database to foster taxonomic identification of malagasy reptiles. We report two new taxa: a species of Boophis , since described as B. ankarafensis, and a candidate new species of microhylid (ge-nus: Stumpffia ). We document range expansions of Boophis tsilo- maro , Cophyla berara, Blaesodactylus ambonihazo beyond their type localities. Along with significant range expansions across a range of taxa, including Blommersia sp. Ca05, Boophys brachychir, in the peninsula is extreme from human exploitation. Unless unsustainable agricultural and pastoral prac-tices encroaching on these habitats halt immediately, both forest and the species that occur there, several of which appear to be local endemics, may be irreversibly
{"title":"Combining old and new evidence to increase the known biodiversity value of the Sahamalaza Peninsula, Northwest Madagascar","authors":"S. Penny, A. Crottini, F. Andreone, A. Bellati, Lovasoa M. S. Rakotozafy, M. Holderied, C. Schwitzer, G. Rosa","doi":"10.1163/18759866-08604002","DOIUrl":"https://doi.org/10.1163/18759866-08604002","url":null,"abstract":"Prior herpetological surveys in 1996 and 2000 identified 14 species of amphibians and 32 species of reptiles from the Sahamalaza Peninsula. This work increases the total number of amphibian and reptile species known from this area to 20 and 43 respectively. To maximise our chances of species detection, survey effort covered the entire wet season and part of the dry season, and utilised a combination of opportunistic searching, transect searching, pitfall trapping, and acoustic recording. We identified species through an integrative taxonomic approach, combining morphological, bio- acoustic and molecular taxonomy. Together, this enabled the detection of cryptic and seasonally inactive species that were missed in the shorter prior surveys that relied on morphological identification alone. The taxonomic identification of amphibians utilised a fragment of the mitochondrial 16S rRNA gene; taxonomic identi- fication of reptiles utilised a fragment of the mitochondrial COI gene, and when necessary, also mitochondrial fragments of the 16S rRNA ND1, ND2, ND4 genes. All sequences were deposited in Genbank and COI sequences were also deposited in the BOLD database to foster taxonomic identification of malagasy reptiles. We report two new taxa: a species of Boophis , since described as B. ankarafensis, and a candidate new species of microhylid (ge-nus: Stumpffia ). We document range expansions of Boophis tsilo- maro , Cophyla berara, Blaesodactylus ambonihazo beyond their type localities. Along with significant range expansions across a range of taxa, including Blommersia sp. Ca05, Boophys brachychir, in the peninsula is extreme from human exploitation. Unless unsustainable agricultural and pastoral prac-tices encroaching on these habitats halt immediately, both forest and the species that occur there, several of which appear to be local endemics, may be irreversibly","PeriodicalId":55210,"journal":{"name":"Contributions to Zoology","volume":"86 1","pages":"273-295"},"PeriodicalIF":2.2,"publicationDate":"2017-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1163/18759866-08604002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43643044","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-22DOI: 10.1163/18759866-08604004
K. Lundin, T. Korshunova, Klas Malmberg, A. Martynov
Based on morphological, bathymetric and molecular data comparing recently collected Arctic and North Atlantic specimens with morphological and bathymetrical data on historical museum specimens, a unique relict population of the deep-water mollusc Dendronotus velifer G.O. Sars, 1878 (Gastropoda: Nudibranchia) is shown to have existed in the deepest section of the Swedish Gullmar Fjord (the only true silled fjord in Sweden) at least until the middle of the 20th century. This population is more than 1500 km away from the nearest point in the species’ distributional range in the Arctic Ocean today. Using an integrative approach incorporating the data mentioned above, including genetic distances, from recently collected specimens taken from the Arctic Ocean, D. velifer is validated and its species status is restored, for the first time in more than a century after being regarded as a junior synonym of D. robustus. The bathymetric data for historical and recently collected specimens of D. velifer demonstrate significant differences compared to the shallow-water species D. robustus. The findings support the necessity of a stronger protection for the unique marine habitats of the Gullmar Fjord.
{"title":"Intersection of historical museum collections and modern systematics: a relict population of the Arctic nudibranch Dendronotus velifer G.O. Sars, 1878 in a Swedish fjord","authors":"K. Lundin, T. Korshunova, Klas Malmberg, A. Martynov","doi":"10.1163/18759866-08604004","DOIUrl":"https://doi.org/10.1163/18759866-08604004","url":null,"abstract":"Based on morphological, bathymetric and molecular data comparing recently collected Arctic and North Atlantic specimens with morphological and bathymetrical data on historical museum specimens, a unique relict population of the deep-water mollusc Dendronotus velifer G.O. Sars, 1878 (Gastropoda: Nudibranchia) is shown to have existed in the deepest section of the Swedish Gullmar Fjord (the only true silled fjord in Sweden) at least until the middle of the 20th century. This population is more than 1500 km away from the nearest point in the species’ distributional range in the Arctic Ocean today. Using an integrative approach incorporating the data mentioned above, including genetic distances, from recently collected specimens taken from the Arctic Ocean, D. velifer is validated and its species status is restored, for the first time in more than a century after being regarded as a junior synonym of D. robustus. The bathymetric data for historical and recently collected specimens of D. velifer demonstrate significant differences compared to the shallow-water species D. robustus. The findings support the necessity of a stronger protection for the unique marine habitats of the Gullmar Fjord.","PeriodicalId":55210,"journal":{"name":"Contributions to Zoology","volume":"86 1","pages":"303-318"},"PeriodicalIF":2.2,"publicationDate":"2017-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1163/18759866-08604004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42594726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-22DOI: 10.1163/18759866-08604003
M. Schilthuizen, Rob Langelaan, N. Hemmings, Wesley van Oostenbrugge, S. Visser
In animals, cell polarity may initiate symmetry breakingvery early in development, ultimately leading to whole-bodyasymmetry. Helical sperm cells, which occur in a variety ofanimal clades, are one class of cells that show clearly visiblebilateral asymmetry. We used scanning-electron microscopyto study coiling direction in helical sperm cells in twogroups of animals that have figured prominently in the spermmorphology literature, namely land snails, Stylommatophora(514 spermatozoa, from 27 individuals, belonging to 8 speciesand 4 families) and songbirds, Passeriformes (486 spermatozoa,from 26 individuals, belonging to 18 species and 8 families).We found that the snail sperm cells were consistently dextral(clockwise), whereas the bird sperm cells were consistentlysinistral (counterclockwise). We discuss reasons why thisapparent evolutionary conservatism of sperm cell chirality mayor may not be related to whole-body asymmetry.
{"title":"An unexpected twist: Sperm cells coil to the right in land snails and to the left in song birds","authors":"M. Schilthuizen, Rob Langelaan, N. Hemmings, Wesley van Oostenbrugge, S. Visser","doi":"10.1163/18759866-08604003","DOIUrl":"https://doi.org/10.1163/18759866-08604003","url":null,"abstract":"In animals, cell polarity may initiate symmetry breakingvery early in development, ultimately leading to whole-bodyasymmetry. Helical sperm cells, which occur in a variety ofanimal clades, are one class of cells that show clearly visiblebilateral asymmetry. We used scanning-electron microscopyto study coiling direction in helical sperm cells in twogroups of animals that have figured prominently in the spermmorphology literature, namely land snails, Stylommatophora(514 spermatozoa, from 27 individuals, belonging to 8 speciesand 4 families) and songbirds, Passeriformes (486 spermatozoa,from 26 individuals, belonging to 18 species and 8 families).We found that the snail sperm cells were consistently dextral(clockwise), whereas the bird sperm cells were consistentlysinistral (counterclockwise). We discuss reasons why thisapparent evolutionary conservatism of sperm cell chirality mayor may not be related to whole-body asymmetry.","PeriodicalId":55210,"journal":{"name":"Contributions to Zoology","volume":"86 1","pages":"297-302"},"PeriodicalIF":2.2,"publicationDate":"2017-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1163/18759866-08604003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47908060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-18DOI: 10.1163/18759866-08604001
J. V. Alphen, J. Arntzen
In a recent paper it was suggested that results published by Kammerer (1911) on the midwife toad could be explained by epigenetics (Vargas et al., 2016). We show that data thought to be fit-ting are based on untested assumptions about the underlying genetic mechanisms. We cite recent studies on the genetics of life history traits, in particular egg-size and number, to show that these assumptions are not realistic. We review aspects of Kam- merer’s experimental results on the midwife toad for which there are no plausible mechanisms, i.e. toads switching from land- breeding to water-breeding in response to an increase in temperature, eggs becoming resistant to moulds within a few generations, the gradual development of nuptial pads, heterochro- nous changes in the development of water-born larvae, and conclude that Kammerer cannot have obtained the results he claims. We argue that natural selection would not have favoured a change in reproductive mode and the loss of parental care and that an epigenetic master switch, affecting many different traits simultaneously, would have either eroded during more than 15 million years of land-breeding and/or would have disappeared by natural selection against it. Finally, we show that Kammerer's data are remarkably close to the invoked Mendelian ratio and too good to be genuine. We conclude that Kammerer’s data are fictitious and that Vargas et al. (2016) have used non-existing data in search of support for
在最近的一篇论文中，有人认为Kammerer(1911)发表的关于助产士蟾蜍的结果可以用表观遗传学来解释(Vargas et al.， 2016)。我们表明，被认为适合的数据是基于关于潜在遗传机制的未经检验的假设。我们引用了最近关于生命史特征的遗传学研究，特别是鸡蛋的大小和数量，来证明这些假设是不现实的。我们回顾了Kam- merer对产蟾蜍的实验结果的各个方面，其中没有合理的机制，即蟾蜍从陆地繁殖转向水中繁殖以应对温度的升高，卵在几代内变得耐霉菌，婚胚的逐渐发育，水中出生的幼虫发育的异时性变化，并得出Kammerer不可能得到他所声称的结果。我们认为，自然选择不会有利于生殖模式的改变和亲代抚育的丧失，而同时影响许多不同性状的表观遗传主开关，要么在超过1500万年的陆地繁殖过程中被侵蚀，要么在自然选择的反对下消失。最后，我们表明Kammerer的数据非常接近于孟德尔比率，而且太好了，不可能是真实的。我们得出结论，Kammerer的数据是虚构的，Vargas等人(2016)使用了不存在的数据来寻找支持
{"title":"The case of the midwife toad revisited","authors":"J. V. Alphen, J. Arntzen","doi":"10.1163/18759866-08604001","DOIUrl":"https://doi.org/10.1163/18759866-08604001","url":null,"abstract":"In a recent paper it was suggested that results published by Kammerer (1911) on the midwife toad could be explained by epigenetics (Vargas et al., 2016). We show that data thought to be fit-ting are based on untested assumptions about the underlying genetic mechanisms. We cite recent studies on the genetics of life history traits, in particular egg-size and number, to show that these assumptions are not realistic. We review aspects of Kam- merer’s experimental results on the midwife toad for which there are no plausible mechanisms, i.e. toads switching from land- breeding to water-breeding in response to an increase in temperature, eggs becoming resistant to moulds within a few generations, the gradual development of nuptial pads, heterochro- nous changes in the development of water-born larvae, and conclude that Kammerer cannot have obtained the results he claims. We argue that natural selection would not have favoured a change in reproductive mode and the loss of parental care and that an epigenetic master switch, affecting many different traits simultaneously, would have either eroded during more than 15 million years of land-breeding and/or would have disappeared by natural selection against it. Finally, we show that Kammerer's data are remarkably close to the invoked Mendelian ratio and too good to be genuine. We conclude that Kammerer’s data are fictitious and that Vargas et al. (2016) have used non-existing data in search of support for","PeriodicalId":55210,"journal":{"name":"Contributions to Zoology","volume":"86 1","pages":"261-272"},"PeriodicalIF":2.2,"publicationDate":"2017-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1163/18759866-08604001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46869698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-10-23DOI: 10.1163/18759866-08603004
J. A. Jurado-Rivera, G. Álvarez, J. Caro, C. Juan, J. Pons, D. Jaume
The molecular systematics of the subterranean amphipod genus Haploginglymus is addressed through the phylogenetic analysis of three DNA gene fragments (nuclear ribosomal 28S and protein-coding Histone 3, plus mitochondrial Cytochrome c Oxidase subunit I). We take advantage of the description of a new species from southern Spain (Haploginglymus geos sp. nov.) to assess the singularity of this genus endemic to the Iberian Peninsula and the inclusion of the morphologically aberrant H. morenoi within Haploginglymus. Our results corroborate the monophyly of the family Niphargidae but shows Niphargus to be paraphyletic as it currently stands, with Haploginglymus appearing nested within it. A strongly supported sister-group relationship between niphargids and the (thalassoid) pseudoniphargids is recovered as well, but we propose the Niphargidae should continue to be considered as a primary limnic group for biogeographic purposes despite its presumed marine derivation. Our findings are in agreement with previous studies that suggest the family Niphargidae originated in the late Cretaceous in the NE Atlantic, from where it eventually expanded across continental Europe.
{"title":"Molecular systematics of Haploginglymus, a genus of subterranean amphipods endemic to the Iberian Peninsula (Amphipoda: Niphargidae)","authors":"J. A. Jurado-Rivera, G. Álvarez, J. Caro, C. Juan, J. Pons, D. Jaume","doi":"10.1163/18759866-08603004","DOIUrl":"https://doi.org/10.1163/18759866-08603004","url":null,"abstract":"The molecular systematics of the subterranean amphipod genus Haploginglymus is addressed through the phylogenetic analysis of three DNA gene fragments (nuclear ribosomal 28S and protein-coding Histone 3, plus mitochondrial Cytochrome c Oxidase subunit I). We take advantage of the description of a new species from southern Spain (Haploginglymus geos sp. nov.) to assess the singularity of this genus endemic to the Iberian Peninsula and the inclusion of the morphologically aberrant H. morenoi within Haploginglymus. Our results corroborate the monophyly of the family Niphargidae but shows Niphargus to be paraphyletic as it currently stands, with Haploginglymus appearing nested within it. A strongly supported sister-group relationship between niphargids and the (thalassoid) pseudoniphargids is recovered as well, but we propose the Niphargidae should continue to be considered as a primary limnic group for biogeographic purposes despite its presumed marine derivation. Our findings are in agreement with previous studies that suggest the family Niphargidae originated in the late Cretaceous in the NE Atlantic, from where it eventually expanded across continental Europe.","PeriodicalId":55210,"journal":{"name":"Contributions to Zoology","volume":"86 1","pages":"239-260"},"PeriodicalIF":2.2,"publicationDate":"2017-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1163/18759866-08603004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48828380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-10-23DOI: 10.1163/18759866-08603002
C. Nagler, J. Høeg, C. Haug, J. Haug
The larval phase of metazoans can be interpreted as a discrete post-embryonic period. Larvae have been usually considered to be small, yet some metazoans possess unusually large larvae, or giant larvae. Here, we report a possible case of such a giant larva from the Upper Jurassic Solnhofen Lithographic limestones (150 million years old, southern Germany), most likely representing an immature cirripede crustacean (barnacles and their relatives). The single specimen was documented with up-to-date imaging methods (macro-photography, stereo-photography, fluorescence photography, composite imaging) and compared with modern cirripede larvae. The identification is based on two conspicuous spine-like extensions in the anterior region of the specimen strongly resembling the so-called fronto-lateral horns, structures exclusively known from cirripede nauplius larvae. Notably, at 5 mm in length the specimen is unusually large for a cirripede nauplius. We therefore consider it to be a giant larva and discuss possible ecological and physiological mechanisms leading to the appearance of giant larvae in other lineages. Further findings of fossil larvae and especially nauplii might give new insights into larval evolution and plankton composition in the past.
{"title":"A possible 150 million years old cirripede crustacean nauplius and the phenomenon of giant larvae","authors":"C. Nagler, J. Høeg, C. Haug, J. Haug","doi":"10.1163/18759866-08603002","DOIUrl":"https://doi.org/10.1163/18759866-08603002","url":null,"abstract":"The larval phase of metazoans can be interpreted as a discrete post-embryonic period. Larvae have been usually considered to be small, yet some metazoans possess unusually large larvae, or giant larvae. Here, we report a possible case of such a giant larva from the Upper Jurassic Solnhofen Lithographic limestones (150 million years old, southern Germany), most likely representing an immature cirripede crustacean (barnacles and their relatives). The single specimen was documented with up-to-date imaging methods (macro-photography, stereo-photography, fluorescence photography, composite imaging) and compared with modern cirripede larvae. The identification is based on two conspicuous spine-like extensions in the anterior region of the specimen strongly resembling the so-called fronto-lateral horns, structures exclusively known from cirripede nauplius larvae. Notably, at 5 mm in length the specimen is unusually large for a cirripede nauplius. We therefore consider it to be a giant larva and discuss possible ecological and physiological mechanisms leading to the appearance of giant larvae in other lineages. Further findings of fossil larvae and especially nauplii might give new insights into larval evolution and plankton composition in the past.","PeriodicalId":55210,"journal":{"name":"Contributions to Zoology","volume":"86 1","pages":"213-227"},"PeriodicalIF":2.2,"publicationDate":"2017-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1163/18759866-08603002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41968718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：