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Hopi E Hoekstra - One of the best experts on this subject based on the ideXlab platform.

  • behavioural mechanisms underlying the evolution of cooperative Burrowing in peromyscus mice
    bioRxiv, 2019
    Co-Authors: Nicole L Bedford, Jesse N Weber, Wenfei Tong, Felix Baier, Rebecca A Greenberg, Hopi E Hoekstra
    Abstract:

    While some behaviours are largely fixed and invariant, others can respond flexibly to different social contexts. Here, we leverage the unique Burrowing behaviour of deer mice (genus Peromyscus) to investigate if and how individuals of three species adapt their behaviour when digging individually versus with partners. First, we find that pairs of mice from monogamous (P. polionotus) but not promiscuous (P. maniculatus, P. leucopus) species cooperatively construct burrows that are approximately twice as long as those dug by individuals and similar in size to burrows found in the wild. However, the length of burrows built by P. polionotus pairs differs: opposite-sex pairs construct longer burrows than same-sex pairs. By designing a novel behavioural assay in which we can observe and measure Burrowing behaviour directly, we find that longer burrows are achieved not by changing individual behaviour, but instead because opposite-sex pairs are more socially cohesive and thus more likely to dig simultaneously, which is a more efficient mode of burrow elongation. Thus, across social contexts, individual Burrowing behaviour appears largely invariant, even when the resultant burrow from pairs of mice differs from expectation based on individual behaviour, underscoring the fixed nature of Burrowing behaviour in Peromyscus mice.

  • evolution and genetics of precocious Burrowing behavior in peromyscus mice
    Current Biology, 2017
    Co-Authors: Hopi E Hoekstra, Hillery C Metz, Nicole L Bedford
    Abstract:

    Summary A central challenge in biology is to understand how innate behaviors evolve between closely related species. One way to elucidate how differences arise is to compare the development of behavior in species with distinct adult traits [1]. Here, we report that Peromyscus polionotus is strikingly precocious with regard to Burrowing behavior, but not other behaviors, compared to its sister species P. maniculatus . In P. polionotus , burrows were excavated as early as 17 days of age, whereas P. maniculatus did not build burrows until 10 days later. Moreover, the well-known differences in burrow architecture between adults of these species— P. polionotus adults excavate long burrows with an escape tunnel, whereas P. maniculatus dig short, single-tunnel burrows [2–4]—were intact in juvenile burrowers. To test whether this juvenile behavior is influenced by early-life environment, we reciprocally cross-fostered pups of both species. Fostering did not alter the characteristic Burrowing behavior of either species, suggesting that these differences are genetic. In backcross hybrids, we show that precocious Burrowing and adult tunnel length are genetically correlated and that a P. polionotus allele linked to tunnel length variation in adults is also associated with precocious onset of Burrowing in juveniles, suggesting that the same genetic region—either a single gene with pleiotropic effects or linked genes—influences distinct aspects of the same behavior at these two life stages. These results raise the possibility that genetic variants affect behavioral drive (i.e., motivation) to burrow and thereby affect both the developmental timing and adult expression of Burrowing behavior.

  • evolution and genetics of precocious Burrowing behavior in peromyscus mice
    bioRxiv, 2017
    Co-Authors: Hillery C Metz, Nicole L Bedford, Hopi E Hoekstra
    Abstract:

    A central challenge in biology is to understand how innate behaviors evolve between closely related species. One way to elucidate how differences arise is to compare the development of behavior in species with distinct adult traits. Here, we report that Peromyscus polionotus is strikingly precocious with regard to Burrowing behavior, but not other behaviors, compared to its sister species P. maniculatus . In P. polionotus , burrows were excavated as early as 17 days of age, while P. maniculatus did not build burrows until 10 days later. Moreover, the well-known differences in burrow architecture between adults of these species -- P. polionotus adults excavate long burrows with an escape tunnel, while P. maniculatus dig short, single-tunnel burrows -- were intact in juvenile burrowers. To test whether this juvenile behavior is influenced by early-life environment, pups of both species were reciprocally cross-fostered. Fostering did not alter the characteristic Burrowing behavior of either species, suggesting these differences are genetic. In backcross F2 hybrids, we show that precocious Burrowing and adult tunnel length are genetically correlated, and that a single P. polionotus allele in a genomic region linked to adult tunnel length is predictive of precocious burrow construction. The co-inheritance of developmental and adult traits indicates the same genetic region -- either a single gene with pleiotropic effects, or closely linked genes -- acts on distinct aspects of the same behavior across life stages. Such genetic variants likely affect behavioral drive (i.e. motivation) to burrow, and thereby affect both the development and adult expression of Burrowing behavior.

  • the evolution of Burrowing behaviour in deer mice genus peromyscus
    Animal Behaviour, 2009
    Co-Authors: Jesse N Weber, Hopi E Hoekstra
    Abstract:

    The evolutionary history of most behaviours remains unknown. Here, we assay Burrowing behaviour of seven species of deer mice in standardized environments to determine how Burrowing evolved in this genus (Peromyscus). We found that several, but not all, species burrow even after many generations of captive breeding. Specifically, there were significant and repeatable differences in both the frequency of Burrowing and burrow shape between species. Moreover, these observed species-specific behaviours resemble those reported in wild mice. These results suggest that there is probably a strong genetic component to Burrowing in deer mice. We also generated a phylogeny for these seven species using characters from four mtDNA and two autosomal loci. Mapping Burrowing behaviour onto this phylogeny suggests a sequence for how complex Burrowing evolves: from small, simple burrows to long, multitunnel burrows with defined entrance and escape tunnels. In particular, the most ‘complex’ burrows of P. polionotus appear to be derived. These behavioural data, when examined in a phylogenetic context, show that even closely related species differ in their Burrowing behaviours and that the most complex burrows probably evolved by the gradual accumulation of genetic change over time.

Hillery C Metz - One of the best experts on this subject based on the ideXlab platform.

  • evolution and genetics of precocious Burrowing behavior in peromyscus mice
    Current Biology, 2017
    Co-Authors: Hopi E Hoekstra, Hillery C Metz, Nicole L Bedford
    Abstract:

    Summary A central challenge in biology is to understand how innate behaviors evolve between closely related species. One way to elucidate how differences arise is to compare the development of behavior in species with distinct adult traits [1]. Here, we report that Peromyscus polionotus is strikingly precocious with regard to Burrowing behavior, but not other behaviors, compared to its sister species P. maniculatus . In P. polionotus , burrows were excavated as early as 17 days of age, whereas P. maniculatus did not build burrows until 10 days later. Moreover, the well-known differences in burrow architecture between adults of these species— P. polionotus adults excavate long burrows with an escape tunnel, whereas P. maniculatus dig short, single-tunnel burrows [2–4]—were intact in juvenile burrowers. To test whether this juvenile behavior is influenced by early-life environment, we reciprocally cross-fostered pups of both species. Fostering did not alter the characteristic Burrowing behavior of either species, suggesting that these differences are genetic. In backcross hybrids, we show that precocious Burrowing and adult tunnel length are genetically correlated and that a P. polionotus allele linked to tunnel length variation in adults is also associated with precocious onset of Burrowing in juveniles, suggesting that the same genetic region—either a single gene with pleiotropic effects or linked genes—influences distinct aspects of the same behavior at these two life stages. These results raise the possibility that genetic variants affect behavioral drive (i.e., motivation) to burrow and thereby affect both the developmental timing and adult expression of Burrowing behavior.

  • evolution and genetics of precocious Burrowing behavior in peromyscus mice
    bioRxiv, 2017
    Co-Authors: Hillery C Metz, Nicole L Bedford, Hopi E Hoekstra
    Abstract:

    A central challenge in biology is to understand how innate behaviors evolve between closely related species. One way to elucidate how differences arise is to compare the development of behavior in species with distinct adult traits. Here, we report that Peromyscus polionotus is strikingly precocious with regard to Burrowing behavior, but not other behaviors, compared to its sister species P. maniculatus . In P. polionotus , burrows were excavated as early as 17 days of age, while P. maniculatus did not build burrows until 10 days later. Moreover, the well-known differences in burrow architecture between adults of these species -- P. polionotus adults excavate long burrows with an escape tunnel, while P. maniculatus dig short, single-tunnel burrows -- were intact in juvenile burrowers. To test whether this juvenile behavior is influenced by early-life environment, pups of both species were reciprocally cross-fostered. Fostering did not alter the characteristic Burrowing behavior of either species, suggesting these differences are genetic. In backcross F2 hybrids, we show that precocious Burrowing and adult tunnel length are genetically correlated, and that a single P. polionotus allele in a genomic region linked to adult tunnel length is predictive of precocious burrow construction. The co-inheritance of developmental and adult traits indicates the same genetic region -- either a single gene with pleiotropic effects, or closely linked genes -- acts on distinct aspects of the same behavior across life stages. Such genetic variants likely affect behavioral drive (i.e. motivation) to burrow, and thereby affect both the development and adult expression of Burrowing behavior.

Amos G Winter - One of the best experts on this subject based on the ideXlab platform.

  • design of a low energy self contained subsea Burrowing robot based on localized fluidization exhibited by atlantic razor clams
    ASME 2014 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, 2014
    Co-Authors: Daniel S Dorsch, Amos G Winter
    Abstract:

    The Atlantic razor clam (Ensis directus) burrows by contracting its valves, fluidizing the surrounding soil and reducing Burrowing drag. Moving through a fluidized, rather than static, soil requires energy that scales linearly with depth, rather than depth squared. In addition to providing an advantage for the animal, localized fluidization may provide significant value to engineering applications such as vehicle anchoring and underwater pipe installation. This paper presents the design of a self-actuated, radially expanding Burrowing mechanism that utilizes E. directus’ Burrowing methods. The device is sized to be a platform for an anchoring system for autonomous underwater vehicles. Scaling relationships presented allow for design of Burrowing systems of different sizes for a variety of applications. The minimum contraction time for a given device size governs how quickly the device must move. Contraction displacement necessary to achieve fluidization is presented. The maximum force for a given size mechanism is also calculated, and allows for sizing actuators for different systems. This paper presents the design of a system that will allow testing of these parameters in a laboratory setting. These relationships provide the optimal sizing and power needs for various size subsea borrowing systems.Copyright © 2014 by ASME

  • identification and evaluation of the atlantic razor clam ensis directus for biologically inspired subsea Burrowing systems
    Integrative and Comparative Biology, 2011
    Co-Authors: Amos G Winter, A E Hosoi
    Abstract:

    Synopsis In this article, we identify and analyze a subsea organism to serve as a model for biologically inspired Burrowing technology to be used in applications such as anchoring, installation of cables, and recovery of oil. After inspecting myriad forms of life that live on or within ocean substrates, the Atlantic razor clam, Ensis directis, stood out as an attractive basis for new Burrowing technology because of its low-energy requirements associated with digging (0.21 J/cm), its speed and depth of burrrowing (� 1 cm/s and 70 cm, respectively), and its size and simplicity relative to man-made machines. As anchoring is a prime application for the technology resulting from this work, the performance of an Ensis directus–based anchoring system was compared to existing technologies. In anchoring force per embedment energy, the E. directus–based anchor beats existing technology by at least an order of magnitude. In anchoring force per weight of device, the biologically inspired system weighs less than half that of current anchors. The article concludes with a review of E. directus’s digging strategy, which involves motions of its valves to locally fluidize the substrate to reduce Burrowing drag and energy, and the successful adaptation of E. directus’s Burrowing mechanisms into an engineering system: the RoboClam Burrowing robot, which, like the animal, uses localized fluidization to achieve digging energy that scales linearly with depth, rather than depth squared, for moving through static soil.

  • Teaching RoboClam to Dig: The design, testing, and genetic algorithm optimization of a biomimetic robot
    2010 IEEE RSJ International Conference on Intelligent Robots and Systems, 2010
    Co-Authors: Amos G Winter, Daniel S Dorsch, Robin L. H. Deits, Anette E. Hosoi, Alexander H. Slocum
    Abstract:

    Razor clams (Ensis directus) are one of nature's most adept Burrowing organisms, able to dig to 70cm at nearly 1cm/s using only 0.21J/cm. We discovered that Ensis reduces Burrowing drag by using motions of its shell to fluidize a thin layer of substrate around its body. We have developed RoboClam, a robot that digs using the same mechanisms as Ensis, to explore how localized fluidization Burrowing can be extended to engineering applications. In this work we present Burrowing performance results of RoboClam in Ensis' habitat. Using a genetic algorithm to optimize RoboClam's kinematics, the machine was able to burrow at speeds comparable to Ensis, with a power law relationship between digging energy and depth of n = 1.17, close to the n = 1 achieved by the animal. Pushing through static soil has a theoretical energy-depth power law of n = 2, which means that Ensis-inspired digging motions can provide exponential energetic savings over existing Burrowing methods.

  • the design and testing of roboclam a machine used to investigate and optimize razor clam inspired Burrowing mechanisms for engineering applications
    ASME 2009 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, 2009
    Co-Authors: Amos G Winter, A E Hosoi, Alexander H. Slocum, Robin L. H. Deits
    Abstract:

    Razor clams (Ensis directus) are one of nature’s most adept Burrowing organisms, able to dig to 70cm at nearly 1cm/s using only 0.21J/cm. Ensis reduces Burrowing drag by using motions of its shell to fluidize a thin layer of substrate around its body. Although these shell motions have an energetic cost, moving through fluidized rather than packed soil results in exponentially lower overall energy consumption. This paper describes the design and testing of RoboClam, a device that mimics Ensis digging methods to understand the limits of razor clam-inspired Burrowing, how they scale for different environments and conditions, and how they can be transferred into engineering applications. Using a genetic optimization solver, we found that RoboClam’s most efficient digging motion mimicked Ensis shell kinematics and yielded a power law relationship between digging energy and depth of n = 1.17, very close to the ideal value of n = 1. Pushing through static soil has a theoretical energy-depth power law of n = 2, which means that Ensis-inspired Burrowing motions can provide exponentially higher energy efficiency and nearly depth-independent drag resistance.© 2009 ASME

Thomas Christoph - One of the best experts on this subject based on the ideXlab platform.

  • cross centre replication of suppressed Burrowing behaviour as an ethologically relevant pain outcome measure in the rat a prospective multicentre study
    Pain, 2016
    Co-Authors: Nick Andrews, Rachel Wodarski, Ada Delaney, Camilla Ultenius, Rosie Morland, Catherine Baastrup, Luke Bryden, Ombretta Caspani, Thomas Christoph
    Abstract:

    : Burrowing, an ethologically relevant rodent behaviour, has been proposed as a novel outcome measure to assess the global impact of pain in rats. In a prospective multicentre study using male rats (Wistar, Sprague-Dawley), replication of suppressed Burrowing behaviour in the complete Freund adjuvant (CFA)-induced model of inflammatory pain (unilateral, 1 mg/mL in 100 µL) was evaluated in 11 studies across 8 centres. Following a standard protocol, data from participating centres were collected centrally and analysed with a restricted maximum likelihood-based mixed model for repeated measures. The total population (TP-all animals allocated to treatment; n = 249) and a selected population (SP-TP animals Burrowing over 500 g at baseline; n = 200) were analysed separately, assessing the effect of excluding "poor" burrowers. Mean baseline Burrowing across studies was 1113 g (95% confidence interval: 1041-1185 g) for TP and 1329 g (1271-1387 g) for SP. Burrowing was significantly suppressed in the majority of studies 24 hours (7 studies/population) and 48 hours (7 TP, 6 SP) after CFA injections. Across all centres, significantly suppressed Burrowing peaked 24 hours after CFA injections, with a Burrowing deficit of -374 g (-479 to -269 g) for TP and -498 g (-609 to -386 g) for SP. This unique multicentre approach first provided high-quality evidence evaluating suppressed Burrowing as robust and reproducible, supporting its use as tool to infer the global effect of pain on rodents. Second, our approach provided important informative value for the use of multicentre studies in the future.

  • pharmacological validation of a refined Burrowing paradigm for prediction of analgesic efficacy in a rat model of sub chronic knee joint inflammation
    European Journal of Pain, 2014
    Co-Authors: Kris Rutten, A Robens, S J Read, Thomas Christoph
    Abstract:

    Background Burrowing is an evolutionarily conserved behaviour in rodents. This study validates a refined Burrowing paradigm (requiring a reduced number of animals) in a rat model of sub-chronic knee joint inflammation and evaluates its sensitivity and specificity for analgesic drugs. Methods Knee joint inflammation in rats was induced by intra-articular injection with complete Freund's adjuvant (CFA). Burrowing performance was assessed at baseline without study drugs, and in CFA-naive and CFA-injected animals following administration of the analgesic drugs naproxen, pregabalin and morphine, each at three doses, or corresponding vehicle (nine rats per dose group). The specificity of the model was evaluated by also testing the anxiogenic drug yohimbine, the stimulant drug dexamphetamine and the anxiolytic drug chlordiazepoxide in CFA-naive and CFA-injected animals. Percentage maximum possible effect (%MPE) was determined by relating the difference between post-CFA and baseline Burrowing performance in each drug dose group to that in the vehicle group in each experiment. Results Burrowing performance in the vehicle groups was decreased by 39.0–59.8% in CFA-injected animals compared with CFA-naive animals. CFA-induced reductions in Burrowing performance were reversed by each of the three analgesic drugs tested. The highest %MPE was 75.2% with naproxen 50 mg/kg, 80.9% with pregabalin 10 mg/kg and 77.0% with morphine 1 mg/kg (all p < 0.05 vs. control). CFA-induced reductions in Burrowing performance were not reversed by yohimbine, dexamphetamine or chlordiazepoxide. Conclusions This study provides pharmacological validation of a refined Burrowing paradigm for analgesic efficacy that exhibits good predictive validity, with high sensitivity and specificity.

  • Burrowing as a non reflex behavioural readout for analgesic action in a rat model of sub chronic knee joint inflammation
    European Journal of Pain, 2014
    Co-Authors: Kris Rutten, A Robens, S J Read, Klaus Schiene, A Leipelt, T Pasqualon, Thomas Christoph
    Abstract:

    Background Innate responses against spontaneous pain are proposed to improve the predictive validity of preclinical analgesia models. Therefore, development and validation of novel readouts is necessary. To investigate whether innate rodent Burrowing is a useful alternative behavioural readout for assessment of analgesic efficacy, a complete Freund's adjuvant (CFA)-induced model of sub-chronic inflammation was used to compare the effects of naproxen, ibuprofen and pregabalin in weight-bearing (WB), open-field (OF) and Burrowing assays. Methods Male Sprague Dawley rats were injected with 150 μL of CFA (2 mg/mL) into the knee (hind leg) 3 days before testing. Naproxen, ibuprofen and pregabalin were administered at different doses 30, 90 and 60 min, respectively, before testing. WB was determined using a rat incapacitance tester; horizontal distance moved and vertical rearings were recorded in an OF; and Burrowing was measured by the weight of gravel remaining in a hollow tube after 60 min. Results CFA-induced arthritis reduced WB, OF activity and Burrowing. Naproxen, pregabalin and ibuprofen treatment normalized WB; however, horizontal OF activity was not improved by any treatment; rearing behaviour was moderately reinstated by ibuprofen (100 mg/kg). In Burrowing, naproxen (100 mg/kg), ibuprofen (31.6 and 100 mg/kg) and pregabalin (10 mg/kg) reversed CFA-induced deficits. Conclusions Burrowing performance is an alternative non-reflex readout relying on innate rodent behaviour that is affected by nociceptive behaviour and can be pharmacologically manipulated. The Burrowing assay appears to be more sensitive than OF assays and is as sensitive as WB assays at distinguishing between analgesic doses and doses that impair locomotion.

Nicole L Bedford - One of the best experts on this subject based on the ideXlab platform.

  • behavioural mechanisms underlying the evolution of cooperative Burrowing in peromyscus mice
    bioRxiv, 2019
    Co-Authors: Nicole L Bedford, Jesse N Weber, Wenfei Tong, Felix Baier, Rebecca A Greenberg, Hopi E Hoekstra
    Abstract:

    While some behaviours are largely fixed and invariant, others can respond flexibly to different social contexts. Here, we leverage the unique Burrowing behaviour of deer mice (genus Peromyscus) to investigate if and how individuals of three species adapt their behaviour when digging individually versus with partners. First, we find that pairs of mice from monogamous (P. polionotus) but not promiscuous (P. maniculatus, P. leucopus) species cooperatively construct burrows that are approximately twice as long as those dug by individuals and similar in size to burrows found in the wild. However, the length of burrows built by P. polionotus pairs differs: opposite-sex pairs construct longer burrows than same-sex pairs. By designing a novel behavioural assay in which we can observe and measure Burrowing behaviour directly, we find that longer burrows are achieved not by changing individual behaviour, but instead because opposite-sex pairs are more socially cohesive and thus more likely to dig simultaneously, which is a more efficient mode of burrow elongation. Thus, across social contexts, individual Burrowing behaviour appears largely invariant, even when the resultant burrow from pairs of mice differs from expectation based on individual behaviour, underscoring the fixed nature of Burrowing behaviour in Peromyscus mice.

  • evolution and genetics of precocious Burrowing behavior in peromyscus mice
    Current Biology, 2017
    Co-Authors: Hopi E Hoekstra, Hillery C Metz, Nicole L Bedford
    Abstract:

    Summary A central challenge in biology is to understand how innate behaviors evolve between closely related species. One way to elucidate how differences arise is to compare the development of behavior in species with distinct adult traits [1]. Here, we report that Peromyscus polionotus is strikingly precocious with regard to Burrowing behavior, but not other behaviors, compared to its sister species P. maniculatus . In P. polionotus , burrows were excavated as early as 17 days of age, whereas P. maniculatus did not build burrows until 10 days later. Moreover, the well-known differences in burrow architecture between adults of these species— P. polionotus adults excavate long burrows with an escape tunnel, whereas P. maniculatus dig short, single-tunnel burrows [2–4]—were intact in juvenile burrowers. To test whether this juvenile behavior is influenced by early-life environment, we reciprocally cross-fostered pups of both species. Fostering did not alter the characteristic Burrowing behavior of either species, suggesting that these differences are genetic. In backcross hybrids, we show that precocious Burrowing and adult tunnel length are genetically correlated and that a P. polionotus allele linked to tunnel length variation in adults is also associated with precocious onset of Burrowing in juveniles, suggesting that the same genetic region—either a single gene with pleiotropic effects or linked genes—influences distinct aspects of the same behavior at these two life stages. These results raise the possibility that genetic variants affect behavioral drive (i.e., motivation) to burrow and thereby affect both the developmental timing and adult expression of Burrowing behavior.

  • evolution and genetics of precocious Burrowing behavior in peromyscus mice
    bioRxiv, 2017
    Co-Authors: Hillery C Metz, Nicole L Bedford, Hopi E Hoekstra
    Abstract:

    A central challenge in biology is to understand how innate behaviors evolve between closely related species. One way to elucidate how differences arise is to compare the development of behavior in species with distinct adult traits. Here, we report that Peromyscus polionotus is strikingly precocious with regard to Burrowing behavior, but not other behaviors, compared to its sister species P. maniculatus . In P. polionotus , burrows were excavated as early as 17 days of age, while P. maniculatus did not build burrows until 10 days later. Moreover, the well-known differences in burrow architecture between adults of these species -- P. polionotus adults excavate long burrows with an escape tunnel, while P. maniculatus dig short, single-tunnel burrows -- were intact in juvenile burrowers. To test whether this juvenile behavior is influenced by early-life environment, pups of both species were reciprocally cross-fostered. Fostering did not alter the characteristic Burrowing behavior of either species, suggesting these differences are genetic. In backcross F2 hybrids, we show that precocious Burrowing and adult tunnel length are genetically correlated, and that a single P. polionotus allele in a genomic region linked to adult tunnel length is predictive of precocious burrow construction. The co-inheritance of developmental and adult traits indicates the same genetic region -- either a single gene with pleiotropic effects, or closely linked genes -- acts on distinct aspects of the same behavior across life stages. Such genetic variants likely affect behavioral drive (i.e. motivation) to burrow, and thereby affect both the development and adult expression of Burrowing behavior.