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1.
Zoolog Sci ; 41(3): 275-280, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38809866

ABSTRACT

Aposematic coloration plays a crucial role in animal defense, and it is shaped by a complex interplay of factors such as physiological limitations and sexual and natural selection. Warty newts within the genus Paramesotriton exhibit significant variation in ventral coloration. In this study, we quantified the percentage of red ventral area to investigate aposematic ventral coloration in Paramesotriton deloustali and P. guangxiensis across eight populations in northern Vietnam. To assess the interaction between predators and the aposematic signals, we conducted experiments employing three types of clay replicas of newts: dorsal, red ventral, and black ventral models. Our findings revealed a significant variation in the red ventral area among different populations. Additionally, a significant correlation was detected between the red ventral area of the newt and the annual temperature range. In clay model experiments, a significant difference in predator attack rates was observed between dorsal and ventral clay models. Interestingly, there was no significant difference in attack rates between red and black ventral types. Our study suggested that the variation in the red ventral area of warty newts is probably influenced by multiple factors, including genetic constraints, sex, ambient environment, and diet. Furthermore, our results supported the effectiveness of displaying aposematic coloration as an antipredator defense mechanism in warty newts. However, variations in body size and the pressure of mammal predation might not play a significant role in determining aposematic coloration.


Subject(s)
Pigmentation , Animals , Pigmentation/physiology , Male , Female , Predatory Behavior/physiology , Biological Mimicry/physiology , Vietnam
2.
Transl Androl Urol ; 13(2): 320-330, 2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38481863

ABSTRACT

Background and Objective: Coronavirus disease 2019 (COVID-19) necessitated a transition to virtual education which limits hands-on opportunities and student engagement. To adapt, a pilot study investigating clay modeling as an alternative educational tool for medical students was incorporated in a virtual and in-person sub-internship for prospective urology applicants. We aim to review the literature supporting the use of clay modeling in medical education as well as describe our experience with the activity as a way to engage trainees and evaluate early surgical skills. Methods: The current literature on clay modeling in medical and early surgical education was reviewed using multiple search queries in PubMed. A total of thirteen publications were identified and analyzed, with zero articles specifically discussing urological anatomy or surgery. The pilot study was conducted through the traditional in-person sub-internship as well as through a novel virtual sub-internship at a single academic U.S. Urology residency program. Students were instructed to create a three-dimensional model of a genitourinary organ using modeling clay. Anonymized surveys were collected. Responses of virtual and in-person students were compared. Key Content and Findings: Clay modeling has been shown in the literature to be beneficial in medical and early surgical education through the use of active learning. Twenty-five total virtual (N=6) and in-person (N=19) students participated in the clay modeling activity. Survey ratings were mixed, with 100% positive responses amongst the virtual group in the areas of "relevance" and "creatively challenging" compared to the in-person cohort, 31.6% of whom responded positively to "relevance" and 47.4% for "creatively challenging" respectively. Overall, students responded positively for the exercise being "creatively challenging" (n=15, 60%) and "enjoyable" (n=16, 64%). Positive results echoed the student perspectives described in the current literature on clay modeling. Conclusions: Clay modeling has previously been used in the in-person classroom setting as a learning supplement or replacement for dissection classes but has not been previously described for use in the virtual learning environment or within the field of Urology. With ongoing need to develop novel teaching modalities, clay modeling may be a unique tool to enhance learning, and evaluate technical skill, and boost engagement for medical trainees.

3.
J Insect Sci ; 22(5)2022 Sep 01.
Article in English | MEDLINE | ID: mdl-36082676

ABSTRACT

Arthropod predators are abundant in turfgrass systems, and they play an important role in managing pests. Understanding the vertical distribution of predation is critical to developing cultural strategies that enhance and conserve predatory services. However, little is known on how the predation is vertically distributed within the turfgrass canopy. Thus, the objective of this study was to determine the vertical distribution of predation within the turfgrass canopy. Clay models were used to emulate the general appearance of Noctuidae caterpillars, to estimate the predatory activity. The choice and no-choice experiments were conducted by placing clay models at 2.54, 5.08, and 7.62 cm from the thatch surface and denoted as lower, intermediate, and upper levels, respectively, within turfgrass canopy. The predator-mediated impressions, paired mark, scratch, deep cut mark, deep distortion, prick, dent, stacked surface impression, scooped mark, granulation, and U-shaped mark, were identified on clay models. The incidence and severity of impressions were significantly greater on clay models placed at the lower canopy level than on those placed at the intermediate and upper canopy levels in the choice and no-choice experiments (P < 0.05). Thus, predators are more likely to find their prey at the soil level. This information can be used to refine management strategies, such as mowing height and insecticide use for effectively managing soil-borne and foliar-feeding arthropod pests and beneficial arthropods.


Subject(s)
Arthropods , Animals , Clay , Predatory Behavior
4.
Zoology (Jena) ; 150: 125987, 2022 02.
Article in English | MEDLINE | ID: mdl-34971911

ABSTRACT

Albinism is a conspicuous and distinctive phenotype arising from the absence of melanin in the integument that has been documented in all major vertebrate groups. With few exceptions, albinism is rare in natural populations, suggesting that it incurs significant fitness costs as compared to wild-type phenotypes. One possible explanation for this rarity is that albinos experience higher predation risk as compared to wild-type individuals. We tested this hypothesis by comparing rates of attack by avian predators on immobile clay model proxies that mimicked wild-type and albino eastern garter snakes (Thamnophis s. sirtalis) at Bond Swamp in central Georgia, USA; two mixed pattern treatments provided intermediate phenotypes for comparison. Surprisingly, we found no difference in attack rate across all four model treatments, nor among pairs of treatments (i.e., wild-type-like vs. albino-like models). This indicates that albino garter snakes are not subject to higher predation risk from birds due to coloration alone, and that other factors (correlated pathologies of albinism, thermoregulatory challenges, mate selection) are likely to be more important in explaining the rarity of albinism in snakes and perhaps other vertebrate groups.


Subject(s)
Albinism , Colubridae , Animals , Birds , Incidence , Predatory Behavior , Snakes
5.
Fertil Steril ; 116(6): 1669-1672, 2021 12.
Article in English | MEDLINE | ID: mdl-34535295

ABSTRACT

OBJECTIVE: To describe our simplified technique for falloposcopic tuboplasty (FT) and demonstrate its principle and results. DESIGN: A step-by-step description of the technique and demonstration of its principle using a clay model. SETTING: Private infertility clinics in Osaka and Tokyo operated by 10 physicians. PATIENT(S): A total of 431 infertile women with a diagnosis of unilateral or bilateral proximal tubal occlusion (6 cm from the uterotubal ostia), between October 2013 and February 2019 were included. These patients underwent routine work-ups for infertility, including a semen analysis, hysterosalpingography, antimüllerian hormone, basal luteinizing hormone/follicle-stimulating hormone and prolactin concentrations during menstruation, postcoital test in the periovulatory period, and estradiol and progesterone concentrations in the middle of the luteal phase. Physicians performed hysterosalpingography to evaluate tubal patency and uterine shape. Saline infusion sonography was not conducted because it does not accurately identify regions of tubal occlusion and/or stenosis. INTERVENTION(S): The principle of our simplified technique for FT is that a hole is located at the side of the FT catheter tip. Therefore, the balloon and fiberscope move away from the catheter line (Fig. 1). The uterotubal ostium is located at the tip-end of the triangle of the uterine cavity. When a balloon is inserted while visualizing the uterotubal ostium at the nearest position to the ostium, the balloon hits the uterine wall. When a balloon is inserted 5-10 mm from the uterotubal ostium without visualization, the balloon may be easily placed in the ostium through its convex angle, allowing it to slide into the uterine wall (Figs. 2 and 3). Step 1: Confirm anteflexion or retroflexion of the uterus by ultrasound. Step 2: Confirm the direction of the uterotubal ostia by hysteroscopy. Step 3: Adjust the angle of the FT catheter according to steps 1 and 2, insert the catheter into the end of the uterus, pull it back 5-10 mm (without visualizing the uterotubal ostia), and then fix it to the forceps. Catheter placement away from the tubal ostium is confirmed by the residual length of the moving part of the catheter. An attending instructor should ask the operator about the feeling of rigidity when the catheter does not advance and then suggest whether to proceed or stop. In the latter case, the catheter is not moved, saline is infused for 1 minute for lubrication, the balloon is pulled back using the fiberscope to remove the bunching of the balloon, and balloon pressure is changed as follows: 6→8→6→10→6 mmHg. Our institutional review board stated that approval was not required because the video describes the technique of our routine procedure. MAIN OUTCOME MEASURE(S): A description of the FT technique using a clay model and a demonstration of its application in our clinic. RESULT(S): The average operative time was 15.4 minutes, and the clinical pregnancy rate was 24.4% (natural conception and intrauterine insemination without in vitro fertilization). No significant differences were observed in the operative time or pregnancy rate among physicians. Approximately 17 FT procedures may be performed using one fiberscope. CONCLUSION(S): Our simplified technique, which was described and demonstrated in this video article, is a feasible and practical approach for performing FT. It provides excellent cost performance by saving fiberscopes. The most important point is "Introduce the balloon and fiberscope 5-10 mm away from the uterotubal ostia without visualizing it." To facilitate learning this technique, we recommend watching the video and then practicing FT without searching for the uterotubal ostia. Physicians master FT without any assistance by an attending instructor in ≤3 attempts.


Subject(s)
Catheterization/methods , Endoscopy/methods , Fallopian Tube Patency Tests/methods , Fallopian Tubes/surgery , Infertility, Female/surgery , Adult , Catheterization/instrumentation , Endoscopy/instrumentation , Fallopian Tube Diseases , Fallopian Tube Patency Tests/instrumentation , Female , Humans , Infertility, Female/diagnosis , Vagina/surgery
6.
PeerJ ; 7: e6487, 2019.
Article in English | MEDLINE | ID: mdl-30828493

ABSTRACT

Artificial prey techniques-wherein synthetic replicas of real organisms are placed in natural habitats-are widely used to study predation in the field. We investigated the extent to which videography could provide additional information to such studies. As a part of studies on aposematism and mimicry of coral snakes (Micrurus) and their mimics, observational data from 109 artificial snake prey were collected from video-recording camera traps in three locations in the Americas (terra firme forest, Tiputini Biodiversity Station, Ecuador; premontane wet forest, Nahá Reserve, Mexico; longleaf pine forest, Southeastern Coastal Plain, North Carolina, USA). During 1,536 camera days, a total of 268 observations of 20 putative snake predator species were recorded in the vicinity of artificial prey. Predators were observed to detect artificial prey 52 times, but only 21 attacks were recorded. Mammals were the most commonly recorded group of predators near replicas (243) and were responsible for most detections (48) and attacks (20). There was no difference between avian or mammalian predators in their probability of detecting replicas nor in their probability of attacking replicas after detecting them. Bite and beak marks left on clay replicas registered a higher ratio of avian:mammalian attacks than videos registered. Approximately 61.5% of artificial prey monitored with cameras remained undetected by predators throughout the duration of the experiments. Observational data collected from videos could provide more robust inferences on the relative fitness of different prey phenotypes, predator behavior, and the relative contribution of different predator species to selection on prey. However, we estimate that the level of predator activity necessary for the benefit of additional information that videos provide to be worth their financial costs is achieved in fewer than 20% of published artificial prey studies. Although we suggest future predation studies employing artificial prey to consider using videography as a tool to inspire new, more focused inquiry, the investment in camera traps is unlikely to be worth the expense for most artificial prey studies until the cost:benefit ratio decreases.

7.
BMC Ecol ; 18(1): 32, 2018 09 10.
Article in English | MEDLINE | ID: mdl-30200934

ABSTRACT

BACKGROUND: Ecological research often involves sampling and manipulating non-model organisms that reside in heterogeneous environments. As such, ecologists often adapt techniques and ideas from industry and other scientific fields to design and build equipment, tools, and experimental contraptions custom-made for the ecological systems under study. Three-dimensional (3D) printing provides a way to rapidly produce identical and novel objects that could be used in ecological studies, yet ecologists have been slow to adopt this new technology. Here, we provide ecologists with an introduction to 3D printing. RESULTS: First, we give an overview of the ecological research areas in which 3D printing is predicted to be the most impactful and review current studies that have already used 3D printed objects. We then outline a methodological workflow for integrating 3D printing into an ecological research program and give a detailed example of a successful implementation of our 3D printing workflow for 3D printed models of the brown anole, Anolis sagrei, for a field predation study. After testing two print media in the field, we show that the models printed from the less expensive and more sustainable material (blend of 70% plastic and 30% recycled wood fiber) were just as durable and had equal predator attack rates as the more expensive material (100% virgin plastic). CONCLUSIONS: Overall, 3D printing can provide time and cost savings to ecologists, and with recent advances in less toxic, biodegradable, and recyclable print materials, ecologists can choose to minimize social and environmental impacts associated with 3D printing. The main hurdles for implementing 3D printing-availability of resources like printers, scanners, and software, as well as reaching proficiency in using 3D image software-may be easier to overcome at institutions with digital imaging centers run by knowledgeable staff. As with any new technology, the benefits of 3D printing are specific to a particular project, and ecologists must consider the investments of developing usable 3D materials for research versus other methods of generating those materials.


Subject(s)
Ecology/methods , Lizards , Printing, Three-Dimensional/instrumentation , Animals , Body Size , Ecology/instrumentation , Imaging, Three-Dimensional , Predatory Behavior , Research Design , Software
8.
Naturwissenschaften ; 104(3-4): 20, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28251304

ABSTRACT

Recent studies suggest that many organisms actively colonize the subterranean environment to avoid climatic stress, exploit new ecological opportunities and reduce competition and predation. Terrestrial salamanders are known to colonize the more stable subterranean habitats mainly to escape external climatic extremes, while the role of predation avoidance remains untested. To better understand the importance of predation, we used clay models of the cave salamander Speleomantes strinatii to compare the predation occurring in woodland and subterranean habitats. Models were positioned in three forests and in three caves in NW Italy. One-hundred eighty-four models were retrieved from the field and 59 (32%) were attacked by predators. Models were attacked on their head more often than expected by chance and, therefore, were perceived by predators as real prey items. In the woodlands, clay models showed a four-time higher probability of being attacked in comparison to caves, suggesting a different level of potential predation risk in these surface habitats. These findings are one of the first experimental evidences that, in terrestrial ecosystems, predation avoidance may contribute to the salamander underground colonization process.


Subject(s)
Caves , Ecosystem , Forests , Urodela/physiology , Animal Distribution , Animals , Italy , Models, Biological
9.
Rev. biol. trop ; 57(3): 859-864, sep. 2009. graf, tab
Article in English | LILACS | ID: lil-637915

ABSTRACT

Predation has been hypothesized to be a strong selective force structuring communities of tropical lizards. Comparisons of perch height and size-based predation frequencies can provide a unique window into understanding how predation might shape habitat selection and morphological patterns in lizards, especially anoles. Here i use plasticine clay models, placed on the trunks of trees and suspended in the canopy to show that predation frequency on clay models differs primarily according to habitat (canopy vs. trunk-ground), but not according to size. These data are discussed in light of observed lizard abundances in the lowland forests of Costa Rica, and are presented as partial explanation for why fewer lizards are found in tree canopies, and more lizards are found on ground-trunk habitats. Rev. Biol. Trop. 57 (3): 859-864. Epub 2009 September 30.


Existe la hipótesis de que la depredación es una fuerte fuerza selectiva que estructura las comunidades de lagartijas tropicales. Las comparaciones de las frecuencias de altura de la percha y de depredación con base en el tamaño pueden proveer una ventana única en el entendimiento de cómo la depredación podría moldear la selección del hábitat y los patrones morfológicos en las lagartijas, especialmente anoles. En este estudio uso modelos de plasticina, ubicados en troncos de árboles y suspendidos en el dosel para mostrar que la frecuencia de depredación en los modelos de plasticina difiere primariamente según el hábitat (dosel vs. tronco-suelo) pero no según el tamaño. Estos datos se discuten a la luz de las abundancias de lagartijas observadas en los bosques de bajura de Costa Rica, y se presentan como una explicación parcial a porqué menos lagartijas se encuentran en los doseles, y más lagartijas se encuentran en los hábitats suelo-tronco.


Subject(s)
Animals , Ecosystem , Lizards/physiology , Predatory Behavior/physiology , Costa Rica , Seasons , Tropical Climate
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