The willistoni group of Drosophila is subdivided into the alagitans, bocainensis and willistoni subgroups, and has been an important model for studying evolutionary processes in the Neotropics for decades. Phylogenetic studies place the bocainensis subgroup as a grade in relation to the monophyletic willistoni subgroup, although these included molecular or morphological data for up to four species of the 12 species included in the first subgroup. Here, we characterized the first nucleotide sequences for three mitochondrial and five nuclear genes of Drosophila bocainensis Pavan & da Cunha, 1947, and employed these for addressing the paraphyly of this subgroup under a coalescent approach. Our results still recovered this paraphyletic relationship, placing D. bocainensis, D. capricorni Dobzhansky & Pavan, 1943 and D. sucinea Patterson & Mainland, 1944 in a basal clade, which diverged around 6.81 million years ago. The relationship of D. nebulosa Sturtevant, 1916 and D. fumipennis Duda, 1925 as a sister clade to the willistoni subgroup was recovered. The possible causes of such paraphyly are discussed.
{"title":"Phylogenetic position of Drosophila bocainensis (Diptera, Drosophilidae) in the willistoni group and the paraphyletic status of the bocainensis subgroup","authors":"Henrique R.M. Antoniolli, M. Deprá, V. Valente","doi":"10.1139/cjz-2023-0054","DOIUrl":"https://doi.org/10.1139/cjz-2023-0054","url":null,"abstract":"The willistoni group of Drosophila is subdivided into the alagitans, bocainensis and willistoni subgroups, and has been an important model for studying evolutionary processes in the Neotropics for decades. Phylogenetic studies place the bocainensis subgroup as a grade in relation to the monophyletic willistoni subgroup, although these included molecular or morphological data for up to four species of the 12 species included in the first subgroup. Here, we characterized the first nucleotide sequences for three mitochondrial and five nuclear genes of Drosophila bocainensis Pavan & da Cunha, 1947, and employed these for addressing the paraphyly of this subgroup under a coalescent approach. Our results still recovered this paraphyletic relationship, placing D. bocainensis, D. capricorni Dobzhansky & Pavan, 1943 and D. sucinea Patterson & Mainland, 1944 in a basal clade, which diverged around 6.81 million years ago. The relationship of D. nebulosa Sturtevant, 1916 and D. fumipennis Duda, 1925 as a sister clade to the willistoni subgroup was recovered. The possible causes of such paraphyly are discussed.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47207898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Animal distributions continue to undergo dramatic shifts in response to environmental change as many ecosystems become altered or transition away from their historic states. The North American Great Plains was historically a vast prairie ecosystem that has been heavily altered into a patchwork of remnant grasslands, industrial agriculture and tracts invaded by woody vegetation. We studied the habitat selection of a forest-dwelling bird, the American woodcock (Scolopax minor Gmelin, 1789), at the westward periphery of the species’ range to determine how this species uses resources in this modified landscape. During the migratory and breeding season (March – May), woodcock tracked using GPS transmitters in Nebraska selected areas with higher proportions of young forest and forests with moist soils, exhibiting similar selection to birds occupying core areas of their range in eastern North America. During the summer, woodcock routinely used (46% of diurnal points) irrigated agricultural fields during the day, which was unexpected for a species that is known to summer in forest-dominated ecosystems. Our study provides evidence for flexible and atypical woodcock habitat selection at the edge of their range. These results add to the growing body of evidence pointing to regional shifts in avian community structure and further underscore the threats of agricultural conversion and woody encroachment to the Great Plains.
随着许多生态系统发生变化或从其历史状态转变，动物分布继续发生巨大变化，以应对环境变化。北美大平原在历史上是一个巨大的草原生态系统，已被严重改变为残余草原、工业农业和被木本植被入侵的大片土地的拼凑。我们研究了一种居住在森林中的鸟类——美国山鸡（Scolopax minor Gmelin，1789）在该物种范围的西部边缘的栖息地选择，以确定该物种如何在这种改良的景观中利用资源。在迁徙和繁殖季节（3月至5月），woodcock在内布拉斯加州使用GPS发射机进行跟踪，选择了幼林比例较高的地区和土壤湿润的森林，表现出与北美东部占据其活动范围核心区域的鸟类相似的选择。在夏季，woodcock通常在白天使用（46%的日间点）灌溉农田，这对于一个已知在森林主导的生态系统中避暑的物种来说是出乎意料的。我们的研究为在其范围边缘灵活和非典型的伍德科克栖息地选择提供了证据。这些结果增加了越来越多的证据，表明鸟类群落结构发生了区域性变化，并进一步强调了农业转型和木材侵占大平原的威胁。
{"title":"Industrial agricultural and woody encroachment associated with American Woodcock habitat selection in an altered grassland ecosystem","authors":"Stephen J. Brenner, J. Jorgensen","doi":"10.1139/cjz-2023-0123","DOIUrl":"https://doi.org/10.1139/cjz-2023-0123","url":null,"abstract":"Animal distributions continue to undergo dramatic shifts in response to environmental change as many ecosystems become altered or transition away from their historic states. The North American Great Plains was historically a vast prairie ecosystem that has been heavily altered into a patchwork of remnant grasslands, industrial agriculture and tracts invaded by woody vegetation. We studied the habitat selection of a forest-dwelling bird, the American woodcock (Scolopax minor Gmelin, 1789), at the westward periphery of the species’ range to determine how this species uses resources in this modified landscape. During the migratory and breeding season (March – May), woodcock tracked using GPS transmitters in Nebraska selected areas with higher proportions of young forest and forests with moist soils, exhibiting similar selection to birds occupying core areas of their range in eastern North America. During the summer, woodcock routinely used (46% of diurnal points) irrigated agricultural fields during the day, which was unexpected for a species that is known to summer in forest-dominated ecosystems. Our study provides evidence for flexible and atypical woodcock habitat selection at the edge of their range. These results add to the growing body of evidence pointing to regional shifts in avian community structure and further underscore the threats of agricultural conversion and woody encroachment to the Great Plains.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43350987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anthropogenic influences caused depletion and subsequent recovery of marine predators, but ecological consequences of altered predator abundance are not well-understood. Although many methods are used to study predator diets, methodological biases and logistical challenges preclude robust sampling schemes. We aimed to compare two non-invasive methods: metabarcoding scat-derived DNA and hard parts analysis of scat for the Northwest Atlantic grey seal (Halichoerus grypus (Fabricius, 1791)), a species that rebounded after near extirpation. We hypothesized metabarcoding would detect a greater diversity and frequency of prey, and that notable differences in diet will be detected since prior studies. Grey seal scat samples (N = 247) were collected between 2018¬-2019 from Monomoy Island, Massachusetts, USA. Metabarcoding detected greater prey richness on average, with more frequent detections of clupeids (Clupeidae) and flatfish (Pleuronectiformes) whereas hard parts analysis more frequently detected phycid hakes (Urophycis spp. Gill, 1863). Combining methods increased detections of 13 prey taxa, with 32 prey taxa identified overall. Skates (Rajidae), flatfish, clupeids, and sand lance (Ammodytes spp. Linnaeus, 1758) were top-occurring prey. Our study highlights the importance of using multiple methods to characterize generalist predator diets using non-invasive techniques and suggests grey seal diet has changed since the early 2000s.
{"title":"A comparative methodological approach to studying the diet of a recovering marine predator, the grey seal (Halichoerus grypus)","authors":"Christina M McCosker, Z. Olson, K. Ono","doi":"10.1139/cjz-2023-0104","DOIUrl":"https://doi.org/10.1139/cjz-2023-0104","url":null,"abstract":"Anthropogenic influences caused depletion and subsequent recovery of marine predators, but ecological consequences of altered predator abundance are not well-understood. Although many methods are used to study predator diets, methodological biases and logistical challenges preclude robust sampling schemes. We aimed to compare two non-invasive methods: metabarcoding scat-derived DNA and hard parts analysis of scat for the Northwest Atlantic grey seal (Halichoerus grypus (Fabricius, 1791)), a species that rebounded after near extirpation. We hypothesized metabarcoding would detect a greater diversity and frequency of prey, and that notable differences in diet will be detected since prior studies. Grey seal scat samples (N = 247) were collected between 2018¬-2019 from Monomoy Island, Massachusetts, USA. Metabarcoding detected greater prey richness on average, with more frequent detections of clupeids (Clupeidae) and flatfish (Pleuronectiformes) whereas hard parts analysis more frequently detected phycid hakes (Urophycis spp. Gill, 1863). Combining methods increased detections of 13 prey taxa, with 32 prey taxa identified overall. Skates (Rajidae), flatfish, clupeids, and sand lance (Ammodytes spp. Linnaeus, 1758) were top-occurring prey. Our study highlights the importance of using multiple methods to characterize generalist predator diets using non-invasive techniques and suggests grey seal diet has changed since the early 2000s.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48698323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Paulina Agata Idczak-Figiel, M. Ostrowski, A. Nowakowska
Snails are often exposed to high variability of ambient temperatures, thus in response to that, they function for prolonged periods in a dormant state. It is known that molecular chaperones (like HSPs) fulfill important functions in maintaining cell homeostasis and the cellular responses to stress and that they are activated in many different species upon exposition to various environmental stressors. HSPs defend organisms from the harmful consequences of heat shock and potentially alternative stressors too. After thorough consideration, we decided to identify proteins that interact with HSP70 and HSP90 in Helix pomatia Linnaeus, 1758 snails under extreme thermal (low and high) and photoperiod (short and long) conditions and at hypometabolic/active states as a response to environmental stress. Identification of proteins that interact with HSPs can define a new tool in molecular basis of adaptation to temperature stress in snails. After performing Co-immunoprecipitation and Western blot we obtained results showing that HSP70 interacts with hemocyanin alphaN and alphaD, and with other isoforms of hemocyanin - hemocyanin beta as well as with Na+/K+-ATPase, whereas HSP90 interacts with hemocyanin alphaN. It means that the chaperones are likely to affect the most important life-supporting systems of snails like respiration and ionic conductivity.
{"title":"The influence of environmental stressful conditions on the interaction between Heat Shock Proteins and chaperone-assisted proteins in land snails, Helix pomatia L.","authors":"Paulina Agata Idczak-Figiel, M. Ostrowski, A. Nowakowska","doi":"10.1139/cjz-2023-0118","DOIUrl":"https://doi.org/10.1139/cjz-2023-0118","url":null,"abstract":"Snails are often exposed to high variability of ambient temperatures, thus in response to that, they function for prolonged periods in a dormant state. It is known that molecular chaperones (like HSPs) fulfill important functions in maintaining cell homeostasis and the cellular responses to stress and that they are activated in many different species upon exposition to various environmental stressors. HSPs defend organisms from the harmful consequences of heat shock and potentially alternative stressors too. After thorough consideration, we decided to identify proteins that interact with HSP70 and HSP90 in Helix pomatia Linnaeus, 1758 snails under extreme thermal (low and high) and photoperiod (short and long) conditions and at hypometabolic/active states as a response to environmental stress. Identification of proteins that interact with HSPs can define a new tool in molecular basis of adaptation to temperature stress in snails. After performing Co-immunoprecipitation and Western blot we obtained results showing that HSP70 interacts with hemocyanin alphaN and alphaD, and with other isoforms of hemocyanin - hemocyanin beta as well as with Na+/K+-ATPase, whereas HSP90 interacts with hemocyanin alphaN. It means that the chaperones are likely to affect the most important life-supporting systems of snails like respiration and ionic conductivity.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42658879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dr. M. Brock Fenton has been intrigued by the diversity of bats throughout his long career, and has combined his research and photography skills to capture the extensive morphological diversity found across the Order Chiroptera. In this paper, we honour Brock’s fascination with diversity by conducting a review of the external and internal characteristics of the bat nose, a morphological feature that Brock’s photographs have beautifully captured in many bat species. Specifically, we explore variation in form and function of the bat rostrum and its role in respiration, echolocation, and olfaction in bats, with an emphasis on the noseleaves of nasal-emitting echolocators, as well as how turbinate morphology may be impacted by nasophonation. While our review is not an extensive dive into all that is known about bat noses, our goal is to highlight the diversity we see in form across the Order Chiroptera, while exploring how function has been shaped by selection, particularly in relation to mode of echolocation signal emission.
M. Brock Fenton博士在他漫长的职业生涯中一直对蝙蝠的多样性很感兴趣，并将他的研究和摄影技巧结合起来，捕捉到了在翼目中发现的广泛的形态多样性。在本文中，我们通过对蝙蝠鼻子的外部和内部特征进行回顾来纪念Brock对多样性的迷恋，Brock的照片漂亮地捕捉到了许多蝙蝠物种的形态特征。具体来说，我们探讨了蝙蝠喙部的形式和功能的变化及其在蝙蝠呼吸、回声定位和嗅觉中的作用，重点研究了鼻腔发射回声定位器的鼻叶，以及鼻甲形态如何受到鼻腔发声的影响。虽然我们的回顾并不是对所有已知的蝙蝠鼻子进行广泛的深入研究，但我们的目标是强调我们在翼目中看到的形式多样性，同时探索功能是如何通过选择形成的，特别是与回声定位信号发射模式有关。
{"title":"The Nose Knows: A Review of the Diversity, Form, and Function of the External and Internal Features of the Bat Nose","authors":"Yvonne A. Dzal, E. Gillam","doi":"10.1139/cjz-2022-0195","DOIUrl":"https://doi.org/10.1139/cjz-2022-0195","url":null,"abstract":"Dr. M. Brock Fenton has been intrigued by the diversity of bats throughout his long career, and has combined his research and photography skills to capture the extensive morphological diversity found across the Order Chiroptera. In this paper, we honour Brock’s fascination with diversity by conducting a review of the external and internal characteristics of the bat nose, a morphological feature that Brock’s photographs have beautifully captured in many bat species. Specifically, we explore variation in form and function of the bat rostrum and its role in respiration, echolocation, and olfaction in bats, with an emphasis on the noseleaves of nasal-emitting echolocators, as well as how turbinate morphology may be impacted by nasophonation. While our review is not an extensive dive into all that is known about bat noses, our goal is to highlight the diversity we see in form across the Order Chiroptera, while exploring how function has been shaped by selection, particularly in relation to mode of echolocation signal emission.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41664293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Euepalpus Townsend, 1908 is a small Neotropical genus of bristle flies (Diptera: Tachinidae: Tachinini), which includes two valid species whose taxonomy is unclear, mainly because males and females are sexually dimorphic. Males exhibit a pair of sexual patches on the dorsal surface of abdominal tergite 5, an unusual feature in Tachinidae. Here, the genus is revised, including a key to species and detailed descriptions and illustrations of the type material and males and females of each species. The male and female terminalia of Euepalpus species are described for the first time. Finally, I discuss the occurrence and distribution of sexual patches in Tachinini.
{"title":"Taxonomic revision of the sexually dimorphic flies of the Neotropical genus Euepalpus Townsend, 1908 (Diptera: Tachinidae), with notes on sexual patches in Tachinini","authors":"F. M. Gudin","doi":"10.1139/cjz-2023-0048","DOIUrl":"https://doi.org/10.1139/cjz-2023-0048","url":null,"abstract":"Euepalpus Townsend, 1908 is a small Neotropical genus of bristle flies (Diptera: Tachinidae: Tachinini), which includes two valid species whose taxonomy is unclear, mainly because males and females are sexually dimorphic. Males exhibit a pair of sexual patches on the dorsal surface of abdominal tergite 5, an unusual feature in Tachinidae. Here, the genus is revised, including a key to species and detailed descriptions and illustrations of the type material and males and females of each species. The male and female terminalia of Euepalpus species are described for the first time. Finally, I discuss the occurrence and distribution of sexual patches in Tachinini.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42234993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Stell, S. Brewer, Lindsay Horne, R. Wright, D. DeVries
Freshwater ecosystems are undergoing rapid thermal shifts, making it increasingly important to understand species-specific responses to these changes. Traditional techniques for determining a species’ thermal tolerance are often lethal and time consuming. Using the enzyme activity associated with the electron transport system (ETS; hereafter referred to as enzyme assay) may provide a non-lethal, rapid, and efficient alternative to traditional techniques for some species. We used largemouth bass Micropterus salmoides Lacepede, 1802 to test the efficacy of using an enzyme assay to determine thermal tolerance and respiratory exploitation in response to variable acclimation temperatures. Three tissue types were dissected from fish acclimated to 20, 25, or 30°C and used in ETS assays at temperatures ranging from 7.5-40°C. While there were significant differences among tissue types and acclimation temperatures, maximal enzyme activity occurred from 25.23-31.91°C. Fish lost equilibrium at 39-42°C in traditional CTmax trials, significantly higher than the upper optimum range determined via enzyme assays. The ratio of enzyme activity to measured whole organism respiration rate decreased with increasing water temperature, with the largest changes occurring at the upper optimum thermal range determined by enzyme assays. Our results indicate ETS analysis may prove useful for obtaining biologically relevant thermal tolerances.
{"title":"Using the electron transport system as an indicator of organismal thermal tolerance and respiratory exploitation.","authors":"E. Stell, S. Brewer, Lindsay Horne, R. Wright, D. DeVries","doi":"10.1139/cjz-2023-0027","DOIUrl":"https://doi.org/10.1139/cjz-2023-0027","url":null,"abstract":"Freshwater ecosystems are undergoing rapid thermal shifts, making it increasingly important to understand species-specific responses to these changes. Traditional techniques for determining a species’ thermal tolerance are often lethal and time consuming. Using the enzyme activity associated with the electron transport system (ETS; hereafter referred to as enzyme assay) may provide a non-lethal, rapid, and efficient alternative to traditional techniques for some species. We used largemouth bass Micropterus salmoides Lacepede, 1802 to test the efficacy of using an enzyme assay to determine thermal tolerance and respiratory exploitation in response to variable acclimation temperatures. Three tissue types were dissected from fish acclimated to 20, 25, or 30°C and used in ETS assays at temperatures ranging from 7.5-40°C. While there were significant differences among tissue types and acclimation temperatures, maximal enzyme activity occurred from 25.23-31.91°C. Fish lost equilibrium at 39-42°C in traditional CTmax trials, significantly higher than the upper optimum range determined via enzyme assays. The ratio of enzyme activity to measured whole organism respiration rate decreased with increasing water temperature, with the largest changes occurring at the upper optimum thermal range determined by enzyme assays. Our results indicate ETS analysis may prove useful for obtaining biologically relevant thermal tolerances.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48695483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hanna Kate Jewell, C.A. Noguera, Clara E. Hael, Julián Torres‐Dowdall, G. Aguilera
For fishes in temperate environments, the timing of seasonal reproduction has been correlated with changes in photoperiod and temperature. In tropical environments, seasonal hydrological patterns have been found to be drivers of the onset of reproduction. Despite these established relationships, data on reproductive seasonality for viviparous fish is limited. Here, we investigate aspects of reproduction in the viviparous fish Jenynsia tucumana (Aguilera and Mirande, 2005) over the course of twelve months in the Salí River basin (Tucumán, Argentina), which is characterized by dry, short winters, and long, tropical summers. Size and reproductive data were collected each month. We found J. tucumana displayed marked sexual dimorphism in size, with females having higher length and weight when compared to males. Larger females have higher fecundities compared to smaller females. The breeding season corresponds with seasonal changes in photoperiod, air temperature, and rainfall, but ends with the arrival of heavy rainfall later in the season. Interestingly, J. tucumana produce and mature oocytes year-round, unlike congeneric species. This may be an adaptive strategy imposed by the irregular flooding of subtropical mountainous river stream habitats, which maintain high productivity well into early autumn.
{"title":"Association of reproduction with seasonality in a subtropical viviparous fish, Jenynsia tucumana (Cyprinodontiformes: Anablepidae)","authors":"Hanna Kate Jewell, C.A. Noguera, Clara E. Hael, Julián Torres‐Dowdall, G. Aguilera","doi":"10.1139/cjz-2023-0096","DOIUrl":"https://doi.org/10.1139/cjz-2023-0096","url":null,"abstract":"For fishes in temperate environments, the timing of seasonal reproduction has been correlated with changes in photoperiod and temperature. In tropical environments, seasonal hydrological patterns have been found to be drivers of the onset of reproduction. Despite these established relationships, data on reproductive seasonality for viviparous fish is limited. Here, we investigate aspects of reproduction in the viviparous fish Jenynsia tucumana (Aguilera and Mirande, 2005) over the course of twelve months in the Salí River basin (Tucumán, Argentina), which is characterized by dry, short winters, and long, tropical summers. Size and reproductive data were collected each month. We found J. tucumana displayed marked sexual dimorphism in size, with females having higher length and weight when compared to males. Larger females have higher fecundities compared to smaller females. The breeding season corresponds with seasonal changes in photoperiod, air temperature, and rainfall, but ends with the arrival of heavy rainfall later in the season. Interestingly, J. tucumana produce and mature oocytes year-round, unlike congeneric species. This may be an adaptive strategy imposed by the irregular flooding of subtropical mountainous river stream habitats, which maintain high productivity well into early autumn.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44445882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wind energy presents many advantages, but windfarms pose risks to wildlife and habitats. We hypothesized that habitat changes caused by the impacts of windfarm construction and wildfire would alter the spatial ecology of Spotted Turtles (Clemmys guttata (Schneider 1792)). In a space-for-time study design, we outfitted 28 turtles with radio transmitters in 3 treatments (Control n=10, Windfarm n=9, Windburn (windfarm and wildfire; n=9)) and located turtles every 3–5 days throughout the active season. We did not detect any significant differences in turtle body condition, home range size, minimum daily distance moved, or microhabitat selection among treatments. Macrohabitat selection differed slightly among treatments; only Windburn turtles used wet depressions on rock barrens, which may indicate that turtles exploited early successional habitats created by wildfire. Turtles did not avoid habitats near windfarm infrastructure yet did not cross service roads unless a culvert was present, highlighting the need to maintain habitat connectivity in modified landscapes. Our findings suggest that Spotted Turtles that survived the acute impacts of the wildfire and windfarm construction were able to navigate the recovering landscape, but a Before–After–Control–Impact study is required to understand the acute and long–term impacts of windfarms and wildfires on turtles.
{"title":"Windfarm and Wildfire: Spatial ecology of an endangered freshwater turtle in a recovering landscape","authors":"Stéphanie J Delay, Ori Urquhart, J. Litzgus","doi":"10.1139/cjz-2023-0100","DOIUrl":"https://doi.org/10.1139/cjz-2023-0100","url":null,"abstract":"Wind energy presents many advantages, but windfarms pose risks to wildlife and habitats. We hypothesized that habitat changes caused by the impacts of windfarm construction and wildfire would alter the spatial ecology of Spotted Turtles (Clemmys guttata (Schneider 1792)). In a space-for-time study design, we outfitted 28 turtles with radio transmitters in 3 treatments (Control n=10, Windfarm n=9, Windburn (windfarm and wildfire; n=9)) and located turtles every 3–5 days throughout the active season. We did not detect any significant differences in turtle body condition, home range size, minimum daily distance moved, or microhabitat selection among treatments. Macrohabitat selection differed slightly among treatments; only Windburn turtles used wet depressions on rock barrens, which may indicate that turtles exploited early successional habitats created by wildfire. Turtles did not avoid habitats near windfarm infrastructure yet did not cross service roads unless a culvert was present, highlighting the need to maintain habitat connectivity in modified landscapes. Our findings suggest that Spotted Turtles that survived the acute impacts of the wildfire and windfarm construction were able to navigate the recovering landscape, but a Before–After–Control–Impact study is required to understand the acute and long–term impacts of windfarms and wildfires on turtles.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48213668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Paul Philip O'Brien, Jeff Bowman, Sasha Newar, Colin J. Garroway
Secondary contact of closely related species may lead to hybridization if reproductive isolation is incomplete. We examined the role of habitat use as a factor contributing to reproductive isolation of northern ( Glaucomys sabrinus (Shaw, 1801)) and southern ( Glaucomys volans (Linnaeus, 1758)) flying squirrels in an area of secondary contact in Ontario, Canada. Specifically, we looked at summer microhabitat use within sites of sympatry and allopatry to test for evidence of reinforcement due to diverging habitat use. We also examined differences in broad-scale habitat features at woodlots to determine predictors of species occurrence across sites. We used 18 years (2002–2019) of flying squirrel summer capture data from six sites along a north–south transect and microhabitat data from vegetation surveys conducted during summer 2016. We found microhabitat variables to be weak predictors of trap-level flying squirrel presence, and we found no evidence of divergence in microhabitat use over the 18 years. Further, we found latitude, not broad-scale habitat, was the strongest predictor of site-level flying squirrel occurrence. Overall, our findings suggest that microhabitat-based isolation is not being reinforced between flying squirrels; however, hybridization may be limited to areas where climate and habitat are suitable for both species.
{"title":"Microhabitat use of northern and southern flying squirrels in a recent hybrid zone","authors":"Paul Philip O'Brien, Jeff Bowman, Sasha Newar, Colin J. Garroway","doi":"10.1139/cjz-2023-0106","DOIUrl":"https://doi.org/10.1139/cjz-2023-0106","url":null,"abstract":"Secondary contact of closely related species may lead to hybridization if reproductive isolation is incomplete. We examined the role of habitat use as a factor contributing to reproductive isolation of northern ( Glaucomys sabrinus (Shaw, 1801)) and southern ( Glaucomys volans (Linnaeus, 1758)) flying squirrels in an area of secondary contact in Ontario, Canada. Specifically, we looked at summer microhabitat use within sites of sympatry and allopatry to test for evidence of reinforcement due to diverging habitat use. We also examined differences in broad-scale habitat features at woodlots to determine predictors of species occurrence across sites. We used 18 years (2002–2019) of flying squirrel summer capture data from six sites along a north–south transect and microhabitat data from vegetation surveys conducted during summer 2016. We found microhabitat variables to be weak predictors of trap-level flying squirrel presence, and we found no evidence of divergence in microhabitat use over the 18 years. Further, we found latitude, not broad-scale habitat, was the strongest predictor of site-level flying squirrel occurrence. Overall, our findings suggest that microhabitat-based isolation is not being reinforced between flying squirrels; however, hybridization may be limited to areas where climate and habitat are suitable for both species.","PeriodicalId":9484,"journal":{"name":"Canadian Journal of Zoology","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136391276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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