Integrative Organismal Biology最新文献

{"title":"Sharks Violate Rensch's Rule for Sexual Size Dimorphism.","authors":"J H Gayford, P C Sternes","doi":"10.1093/iob/obae025","DOIUrl":"10.1093/iob/obae025","url":null,"abstract":"<p><p>Systematic trends in body size variation exist in a multitude of vertebrate radiations, however their underlying ecological and evolutionary causes remain poorly understood. Rensch's rule describes one such trend-in which the scaling of sexual size dimorphism (SSD) depends on which sex is larger. Where SSD is male-biased, SSD should scale hyperallometrically, as opposed to hypoallometrically where SSD is female-biased. The evidence for Rensch's rule is mixed, and comes from a small subset of total vertebrate diversity. We conducted the first empirical test of Rensch's rule in sharks, seeking to confirm or refute a long-hypothesied trend. We find that sharks violate Rensch's rule, as the magnitude of SSD increases with body size despite sharks predominantly exhibiting female-biased SSD. This adds to a growing literature of vertebrate clades that appear not to follow Rensch's rule, suggesting the absence of a single, conserved scaling trend for SSD amongst vertebrates. It is likely that selection associated with fecundity results in the \"inverse Rensch's rule\" observed in sharks, although additional studies will be required to fully reveal the factors underlying SSD variation in this clade.</p>","PeriodicalId":13666,"journal":{"name":"Integrative Organismal Biology","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11247179/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141619819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Variation and variability in skeletal ossification of the gray short-tailed opossum, Monodelphis domestica","authors":"Zachary S Morris, Mathew W Colbert, Timothy B. Rowe","doi":"10.1093/iob/obae024","DOIUrl":"https://doi.org/10.1093/iob/obae024","url":null,"abstract":"\u0000 By reconstructing and comparing the sequence of ontogenetic (embryonic development and post-natal growth) events across species, developmental biologists have gained unique insights into the key processes underlying the evolution of modern lineages and their extinct relatives. However, despite the importance of intraspecific variation to evolutionary transformation and lineage divergence, variation in the sequence of developmental events is seldom acknowledged. Thus, how much variation or variability should be expected during ontogeny remains poorly understood and it is an open question to what extent it impacts interspecific comparisons of developmental patterns. To address this crucial question, we studied the skeletal development of the important biomedical and developmental model organism, Monodelphis domestica. We investigated cranial, forelimb, and hindlimb elements using Ontogenetic Sequence Analysis (OSA) to quantify and assess the full range of variation and variability in the sequence of ossification. Our study documented that previously unrecognized variation exists during M. domestica ontogeny — with over 5000 sequences for the full 92 event analysis. Further, OSA revealed unexpectedly high variability (i.e., the propensity to express variation) in the sequence of ossification for the skull and across the entire skeleton. Reconstructed modal sequences were generally in agreement with previously recognized patterns, including earlier ossification of the facial skeleton and a slight offset between forelimb and hindlimb development. However, the full range of variation shows that the majority of specimens in our analysis followed developmental trajectories distinct from those recovered by prior studies. This level of variation is quite remarkable and demonstrates the importance of assessing intraspecific ontogenetic variation. By quantifying sequence polymorphism and studying how developmental variation and variability differ among species, we can clarify more precisely how developmental patterns differ among species and gain insights into how ontogeny itself evolves.","PeriodicalId":13666,"journal":{"name":"Integrative Organismal Biology","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141683039","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}

{"title":"Morphology and Mechanics of the Fin Whale Esophagus: The Key to Fast Processing of Large Food Volumes by Rorquals.","authors":"K N Gil, A W Vogl, R E Shadwick","doi":"10.1093/iob/obae020","DOIUrl":"10.1093/iob/obae020","url":null,"abstract":"<p><p>Lunge feeding rorqual whales feed by engulfing a volume of prey laden water that can be as large as their own body. Multiple feeding lunges occur during a single foraging dive and the time between each lunge can be as short as 30 s (Goldbogen et al. 2013). During this short inter-lunge time, water is filtered out through baleen to concentrate prey in the oral cavity, and then the prey is swallowed prior to initiating the next lunge. Prey density in the ocean varies greatly, and despite the potential of swallowing a massive volume of concentrated prey as a slurry, the esophagus of rorqual whales has been anecdotally described as unexpectedly narrow with a limited capacity to expand. How rorquals swallow large quantities of food down a narrow esophagus during a limited inter-lunge time remains unknown. Here, we show that the small diameter muscular esophagus in the fin whale is optimized to transport a slurry of food to the stomach. A thick wall of striated muscle occurs at the pharyngeal end of the esophagus which, together with the muscular wall of the pharynx, may generate a pressure head for transporting the food down the esophagus to the stomach as a continuous stream rather than separating the food into individual boluses swallowed separately. This simple model is consistent with estimates of prey density and stomach capacity. Rorquals may be the only animals that capture a volume of food too large to swallow as a single intact bolus without oral processing, so the adaptations of the esophagus are imperative for transporting these large volumes of concentrated food to the stomach during a time-limited dive involving multiple lunges.</p>","PeriodicalId":13666,"journal":{"name":"Integrative Organismal Biology","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11221840/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141497949","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Amphibian Segmentation Clock Models Suggest How Large Genome and Cell Sizes Slow Developmental Rate.","authors":"A Taylor, A Prasad, R Lockridge Mueller","doi":"10.1093/iob/obae021","DOIUrl":"10.1093/iob/obae021","url":null,"abstract":"<p><p>Evolutionary increases in genome size, cell volume, and nuclear volume have been observed across the tree of life, with positive correlations documented between all three traits. Developmental tempo slows as genomes, nuclei, and cells increase in size, yet the driving mechanisms are poorly understood. To bridge this gap, we use a mathematical model of the somitogenesis clock to link slowed developmental tempo with changes in intra-cellular gene expression kinetics induced by increasing genome size and nuclear volume. We adapt a well-known somitogenesis clock model to two model amphibian species that vary 10-fold in genome size: <i>Xenopus laevis</i> (3.1 Gb) and <i>Ambystoma mexicanum</i> (32 Gb). Based on simulations and backed by analytical derivations, we identify parameter changes originating from increased genome and nuclear size that slow gene expression kinetics. We simulate biological scenarios for which these parameter changes mathematically recapitulate slowed gene expression in <i>A. mexicanum</i> relative to <i>X. laevis</i>, and we consider scenarios for which additional alterations in gene product stability and chromatin packing are necessary. Results suggest that slowed degradation rates as well as changes induced by increasing nuclear volume and intron length, which remain relatively unexplored, are significant drivers of slowed developmental tempo.</p>","PeriodicalId":13666,"journal":{"name":"Integrative Organismal Biology","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11245677/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141616317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Buffered Lugol's Iodine Preserves DNA Fragment Lengths.","authors":"P M Gignac, D Valdez, A C Morhardt, L M Lynch","doi":"10.1093/iob/obae017","DOIUrl":"10.1093/iob/obae017","url":null,"abstract":"<p><p>Museum collections play a pivotal role in the advancement of biological science by preserving phenotypic and genotypic history and variation. Recently, contrast-enhanced X-ray computed tomography (CT) has aided these advances by allowing improved visualization of internal soft tissues. However, vouchered specimens could be at risk if staining techniques are destructive. For instance, the pH of unbuffered Lugol's iodine (I₂KI) may be low enough to damage deoxyribonucleic acid (DNA). The extent of this risk is unknown due to a lack of rigorous evaluation of DNA quality between control and experimental samples. Here, we used formalin-fixed mice to document DNA concentrations and fragment lengths in nonstained, ethanol-preserved controls and 3 iodine-based staining preparations: (1) 1.25% weight-by-volume (wt/vol.) alcoholic iodine (I₂E); (2) 3.75% wt/vol. I₂KI; and (3) 3.75% wt/vol. buffered I₂KI. We tested a null hypothesis of no significant difference in DNA concentrations and fragment lengths between control and treatment samples. We found that DNA concentration decreases because of staining-potentially an effect of measuring intact double-stranded DNA only. Fragment lengths, however, were significantly higher for buffered I₂KI and control samples, which were not, themselves, significantly different. Our results implicate buffered I₂KI as the appropriate choice for contrast-enhanced CT imaging of museum wet collections to safely maximize their potential for understanding genetic and phenotypic diversity.</p>","PeriodicalId":13666,"journal":{"name":"Integrative Organismal Biology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11182668/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141418837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Four-bar geometry is shared among ecologically divergent fish species","authors":"H Camarillo, E D Burress, M M Muñoz","doi":"10.1093/iob/obae019","DOIUrl":"https://doi.org/10.1093/iob/obae019","url":null,"abstract":"\u0000 Understanding the factors that influence morphological evolution is a major goal in biology. One such factor is the ability to acquire and process prey. Prey hardness and evasiveness are important properties that can impact evolution of the jaws. Similar diets and biomechanical systems have repeatedly evolved among fish lineages, providing an opportunity to test for shared patterns of evolution across distantly related organisms. Four-bar linkages are structures often used by animals to transmit force and motion during feeding, and which provide an excellent system to understand the impact of diet on morphological and biomechanical evolution. Here, we tested how diet influences the evolutionary dynamics of the oral four-bar linkage system in wrasses (Family: Labridae) and cichlids (Family: Cichlidae). We found that shifts in prey hardness/evasiveness are associated with limited modifications in four-bar geometry across these two distantly related fish lineages. Wrasse and cichlid four-bar systems largely exhibit many-to-one mapping in response to dietary shifts. Across two iconic adaptive radiations of fishes an optimal four-bar geometry has largely been co-opted for different dietary functions during their extensive ecological diversification. Given the exceptional jaw diversity of both lineages, many-to-one mapping of morphology to mechanical properties may be a core feature of fish adaptive radiation.","PeriodicalId":13666,"journal":{"name":"Integrative Organismal Biology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141342825","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}

{"title":"Surfperches versus Damselfishes: Trophic Evolution in Closely Related Pharyngognath Fishes with Highly Divergent Reproductive Strategies.","authors":"W J Cooper, M R Conith, A J Conith","doi":"10.1093/iob/obae018","DOIUrl":"https://doi.org/10.1093/iob/obae018","url":null,"abstract":"<p><p>Surfperches and damselfishes are very closely related ovalentarians with large reproductive differences. Damselfishes are typical of most Ovalentaria in that they lay demersal eggs that hatch into small, free-feeding larvae. Surfperches are unusual among ovalentarians and most acanthomorphs in having prolonged internal development. They are born at an advanced stage, some as adults, and bypass the need to actively feed throughout an extended period of ontogeny. Damselfishes and surfperches possess the same modifications of the fifth branchial arch that allow them to perform advanced food processing within the pharynx. This condition (pharyngognathy) has large effects on the evolution of feeding mechanics and trophic ecology. Although the evolution of pharyngognaths has received considerable attention, the effects of different reproductive strategies on their diversification have not been examined. We compared head shape evolution in surfperches and damselfishes using geometric morphometrics, principal component analyses, and multiple phylogenetic-comparative techniques. We found that they have similar mean head shapes, that their primary axes of shape variation are comparable and distinguish benthic-feeding and pelagic-feeding forms in each case, and that, despite large differences in crown divergence times, their head shape disparities are not significantly different. Several lines of evidence suggest that evolution has been more constrained in damselfishes: Head shape is evolving faster in surfperches, more anatomical traits have undergone correlated evolution in damselfishes, there is significant phylogenetic signal in damselfish evolution (but not surfperches), and damselfishes exhibit significant allometry in head shape that is not present in surfperches.</p>","PeriodicalId":13666,"journal":{"name":"Integrative Organismal Biology","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11210498/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141467790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Meioflume: A New System for Observing the Interstitial Behavior of Meiofauna.","authors":"W M Ballentine, K M Dorgan","doi":"10.1093/iob/obae016","DOIUrl":"10.1093/iob/obae016","url":null,"abstract":"<p><p>Meiofauna (benthic invertebrates < 1 mm in size) facilitate sediment biogeochemical cycling, alter sediment microbial community structure, and serve as an important trophic link between benthic micro- and macrofauna, yet the behaviors that mechanistically link individuals to their ecological effects are largely unknown. Meiofauna are small and sediments are opaque, making observing the <i>in situ</i> activities of these animals challenging. We developed the Meioflume, a small, acrylic flow tunnel filled with grains of cryolite, a transparent sand analog, to simulate the <i>in situ</i> conditions experienced by meiofauna in an observable lab environment. The Meioflume has a working area (28.57 mm × 10.16 mm × 1 mm) that is small enough to quickly locate fauna and clearly observe behavior but large enough that animals are not tightly confined. When connected to a syringe press, the Meioflume can produce low velocity flows consistently and evenly across the width of its working area while retaining the contents. To demonstrate its functionality in observing the behavior of meiofauna, we placed individual meiofaunal animals (a protodrilid annelid, a harpacticoid copepod, and a platyhelminth flatworm) in Meioflumes and filmed their behavioral response to a sudden initiation of porewater flow. All animals were clearly visible within the flume and could be observed responding to the onset of flow. The design and construction of the Meioflume make it an accessible, affordable tool for researchers. This experimental system could be modified to address many questions in meiofaunal ecology, such as studying behavior in response to chemical cues, allowing us to observe meiofaunal behaviors to better understand their ecological effects.</p>","PeriodicalId":13666,"journal":{"name":"Integrative Organismal Biology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11177882/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141330852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dental Dynamics: a fast new tool for quantifying tooth and jaw biomechanics in 3D Slicer","authors":"K. Cohen, A. R. Fitzpatrick, J. M. Huie","doi":"10.1093/iob/obae015","DOIUrl":"https://doi.org/10.1093/iob/obae015","url":null,"abstract":"\u0000 Teeth reveal how organisms interact with their environment. Biologists have long looked at the diverse form and function of teeth to study the evolution of feeding, fighting, and development. The exponential rise in the quantity and accessibility of computed tomography (CT) data has enabled morphologists to study teeth at finer resolutions and larger macroevolutionary scales. Measuring tooth function is no easy task, in fact, much of our mechanical understanding is derived from dental shape. Categorical descriptors of tooth shape such as morphological homodonty and heterodonty, overlook nuances in function by reducing tooth diversity for comparative analysis. The functional homodonty method quantitatively assesses the functional diversity of whole dentitions from tooth shape. This method uses tooth surface area and position to calculate the transmission of stress and estimates a threshold for functionally homodont teeth through bootstrapping and clustering techniques. However, some vertebrates have hundreds or thousands of teeth and measuring the shape and function of every individual tooth can be a painstaking task. Here we present Dental Dynamics, a module for 3D slicer that allows for the fast and precise quantification of dentitions and jaws. The tool automates the calculation of several tooth traits classically used to describe form and function (i.e., aspect ratio, mechanical advantage, force, etc.). To demonstrate the usefulness of our module we used Dental Dynamics to quantify 745 teeth across 20 salamanders that exhibit diverse ecologies. We coupled these data with the functional homodonty method to investigate the hypothesis that arboreal Aneides salamanders have novel tooth functions. Dental Dynamics provides a new and fast way to measure teeth and increases the accessibility of the functional homodonty method. We hope Dental Dynamics will encourage further theoretical and methodological development for quantifying and studying teeth.","PeriodicalId":13666,"journal":{"name":"Integrative Organismal Biology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140993943","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}

{"title":"Ground Reaction Forces and Energy Exchange During Underwater Walking.","authors":"K M Gamel, S Pinti, H C Astley","doi":"10.1093/iob/obae013","DOIUrl":"10.1093/iob/obae013","url":null,"abstract":"<p><p>Underwater walking was a crucial step in the evolutionary transition from water to land. Underwater walkers use fins and/or limbs to interact with the benthic substrate and produce propulsive forces. The dynamics of underwater walking remain poorly understood due to the lack of a sufficiently sensitive and waterproof system to measure substrate reaction forces (SRFs). Using an underwater force plate (described in our companion paper), we quantify SRFs during underwater walking in axolotls (<i>Ambystoma mexicanum</i>) and Spot prawn (<i>Pandalus platyceros</i>), synchronized with videography. The horizontal propulsive forces were greater than the braking forces in both species to overcome hydrodynamic drag. In axolotls, potential energy (PE) fluctuations were far smaller than kinetic energy (KE) fluctuations due to high buoyant support (97%), whereas the magnitudes were similar in the prawn due to lower buoyant support (93%). However, both species show minimal evidence of exchange between KE and PE, which, along with the effects of hydrodynamic drag, is incompatible with inverted pendulum dynamics. Our results show that, despite their evolutionary links, underwater walking has fundamentally different dynamics compared with terrestrial walking and emphasize the substantial consequences of differences in body plan in underwater walking.</p>","PeriodicalId":13666,"journal":{"name":"Integrative Organismal Biology","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11191838/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141442551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}