X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    Misinformed leaders lose influence over pigeon flocks
    The Royal Society ; 2016
    In:  Biology Letters Vol. 12, No. 9 ( 2016-09), p. 20160544-
    Details
    In: Biology Letters, The Royal Society, Vol. 12, No. 9 ( 2016-09), p. 20160544-
    Abstract: In animal groups where certain individuals have disproportionate influence over collective decisions, the whole group's performance may suffer if these individuals possess inaccurate information. Whether in such situations leaders can be replaced in their roles by better-informed group mates represents an important question in understanding the adaptive consequences of collective decision-making. Here, we use a clock-shifting procedure to predictably manipulate the directional error in navigational information possessed by established leaders within hierarchically structured flocks of homing pigeons ( Columba livia ). We demonstrate that in the majority of cases when leaders hold inaccurate information they lose their influence over the flock. In these cases, inaccurate information is filtered out through the rearrangement of hierarchical positions, preventing errors by former leaders from propagating down the hierarchy. Our study demonstrates that flexible decision-making structures can be valuable in situations where ‘bad’ information is introduced by otherwise influential individuals.
    Type of Medium: Online Resource
    ISSN: 1744-9561 , 1744-957X
    URL: Article
    DOI: 10.1098/rsbl.2016.0544
    Language: English
    Publisher: The Royal Society
    Publication Date: 2016
    detail.hit.zdb_id: 2103283-X
    SSG: 12
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 2
    Online Resource
    Online Resource
    Lack of experience-based stratification in homing pigeon leadership hierarchies
    The Royal Society ; 2016
    In:  Royal Society Open Science Vol. 3, No. 1 ( 2016-01), p. 150518-
    Details
    In: Royal Society Open Science, The Royal Society, Vol. 3, No. 1 ( 2016-01), p. 150518-
    Abstract: In societies that make collective decisions through leadership, a fundamental question concerns the individual attributes that allow certain group members to assume leadership roles over others. Homing pigeons form transitive leadership hierarchies during flock flights, where flock members are ranked according to the average time differences with which they lead or follow others' movement. Here, we test systematically whether leadership ranks in navigational hierarchies are correlated with prior experience of a homing task. We constructed experimental flocks of pigeons with mixed navigational experience: half of the birds within each flock had been familiarized with a specific release site through multiple previous releases, while the other half had never been released from the same site. We measured the birds' hierarchical leadership ranks, then switched the same birds' roles at a second site to test whether the relative hierarchical positions of the birds in the two subsets would reverse in response to the reversal in levels of experience. We found that while across all releases the top hierarchical positions were occupied by experienced birds significantly more often than by inexperienced ones, the remaining experienced birds were not consistently clustered in the top half—in other words, the network did not become stratified. We discuss our results in light of the adaptive value of structuring leadership hierarchies according to ‘merit’ (here, navigational experience).
    Type of Medium: Online Resource
    ISSN: 2054-5703
    URL: Article
    DOI: 10.1098/rsos.150518
    Language: English
    Publisher: The Royal Society
    Publication Date: 2016
    detail.hit.zdb_id: 2787755-3
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 3
    Online Resource
    Online Resource
    Detection and characterization of chemotaxis without cell tracking
    The Royal Society ; 2021
    In:  Journal of The Royal Society Interface Vol. 18, No. 176 ( 2021-03)
    Details
    In: Journal of The Royal Society Interface, The Royal Society, Vol. 18, No. 176 ( 2021-03)
    Abstract: Swarming has been observed in various biological systems from collective animal movements to immune cells. In the cellular context, swarming is driven by the secretion of chemotactic factors. Despite the critical role of chemotactic swarming, few methods to robustly identify and quantify this phenomenon exist. Here, we present a novel method for the analysis of time series of positional data generated from realizations of agent-based processes. We convert the positional data for each individual time point to a function measuring agent aggregation around a given area of interest, hence generating a functional time series. The functional time series, and a more easily visualized swarming metric of agent aggregation derived from these functions, provide useful information regarding the evolution of the underlying process over time. We extend our method to build upon the modelling of collective motility using drift–diffusion partial differential equations (PDEs). Using a functional linear model, we are able to use the functional time series to estimate the drift and diffusivity terms associated with the underlying PDE. By producing an accurate estimate for the drift coefficient, we can infer the strength and range of attraction or repulsion exerted on agents, as in chemotaxis. Our approach relies solely on using agent positional data. The spatial distribution of diffusing chemokines is not required, nor do individual agents need to be tracked over time. We demonstrate our approach using random walk simulations of chemotaxis and experiments investigating cytotoxic T cells interacting with tumouroids.
    Type of Medium: Online Resource
    ISSN: 1742-5662
    URL: Article
    DOI: 10.1098/rsif.2020.0879
    Language: English
    Publisher: The Royal Society
    Publication Date: 2021
    detail.hit.zdb_id: 2156283-0
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 4
    Online Resource
    Online Resource
    T cell morphodynamics reveal periodic shape oscillations in three-dimensional migration
    The Royal Society ; 2022
    In:  Journal of The Royal Society Interface Vol. 19, No. 190 ( 2022-05)
    Details
    In: Journal of The Royal Society Interface, The Royal Society, Vol. 19, No. 190 ( 2022-05)
    Abstract: T cells use sophisticated shape dynamics (morphodynamics) to migrate towards and neutralize infected and cancerous cells. However, there is limited quantitative understanding of the migration process in three-dimensional extracellular matrices (ECMs) and across timescales. Here, we leveraged recent advances in lattice light-sheet microscopy to quantitatively explore the three-dimensional morphodynamics of migrating T cells at high spatio-temporal resolution. We first developed a new shape descriptor based on spherical harmonics, incorporating key polarization information of the uropod. We found that the shape space of T cells is low-dimensional. At the behavioural level, run-and-stop migration modes emerge at approximately 150 s, and we mapped the morphodynamic composition of each mode using multiscale wavelet analysis, finding ‘stereotyped’ motifs. Focusing on the run mode, we found morphodynamics oscillating periodically (every approx. 100 s) that can be broken down into a biphasic process: front-widening with retraction of the uropod, followed by a rearward surface motion and forward extension, where intercalation with the ECM in both of these steps likely facilitates forward motion. Further application of these methods may enable the comparison of T cell migration across different conditions (e.g. differentiation, activation, tissues and drug treatments) and improve the precision of immunotherapeutic development.
    Type of Medium: Online Resource
    ISSN: 1742-5662
    URL: Article
    DOI: 10.1098/rsif.2022.0081
    Language: English
    Publisher: The Royal Society
    Publication Date: 2022
    detail.hit.zdb_id: 2156283-0
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 5
    Online Resource
    Online Resource
    Validating two-dimensional leadership models on three-dimensionally structured fish schools
    The Royal Society ; 2017
    In:  Royal Society Open Science Vol. 4, No. 1 ( 2017-01), p. 160804-
    Details
    In: Royal Society Open Science, The Royal Society, Vol. 4, No. 1 ( 2017-01), p. 160804-
    Abstract: Identifying leader–follower interactions is crucial for understanding how a group decides where or when to move, and how this information is transferred between members. Although many animal groups have a three-dimensional structure, previous studies investigating leader–follower interactions have often ignored vertical information. This raises the question of whether commonly used two-dimensional leader–follower analyses can be used justifiably on groups that interact in three dimensions. To address this, we quantified the individual movements of banded tetra fish ( Astyanax mexicanus ) within shoals by computing the three-dimensional trajectories of all individuals using a stereo-camera technique. We used these data firstly to identify and compare leader–follower interactions in two and three dimensions, and secondly to analyse leadership with respect to an individual's spatial position in three dimensions. We show that for 95% of all pairwise interactions leadership identified through two-dimensional analysis matches that identified through three-dimensional analysis, and we reveal that fish attend to the same shoalmates for vertical information as they do for horizontal information. Our results therefore highlight that three-dimensional analyses are not always required to identify leader–follower relationships in species that move freely in three dimensions. We discuss our results in terms of the importance of taking species' sensory capacities into account when studying interaction networks within groups.
    Type of Medium: Online Resource
    ISSN: 2054-5703
    URL: Article
    DOI: 10.1098/rsos.160804
    Language: English
    Publisher: The Royal Society
    Publication Date: 2017
    detail.hit.zdb_id: 2787755-3
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
Nothing or not found what you are looking for? Please check your search query or use the Interlibrary Loan Search.
Close ⊗
This website uses cookies and the analysis tool Matomo. Further information can be found on the KOBV privacy pages