Tootfinder

A minimal wake-vortex model explains formation flight of flapping birds
Olivia Pomerenk, Kenneth S. Breuer
https://arxiv.org/abs/2602.22043 https://arxiv.org/pdf/2602.22043 https://arxiv.org/html/2602.22043
arXiv:2602.22043v1 Announce Type: new
Abstract: Collective patterns of motion emerge across biological taxa: insects swarm, fish school, and birds flock. In particular, large migratory birds form strikingly ordered V-shaped formations, which experiments and direct numerical simulations have demonstrated provide substantial energetic benefits during long-distance flight. However, the precise aerodynamic and morphological mechanisms underlying these benefits remain unclear. In this work, we develop a reduced-order model of the wake-vortex interactions between two flapping birds flying in tandem. The model retains essential unsteady flapping dynamics while remaining computationally tractable. By optimizing over a six-dimensional state space, which comprises the follower's three-dimensional relative position and three independent flapping parameters, we identify the energetically optimal leader-follower configuration of northern bald ibises. The predicted optimum agrees quantitatively with live-bird measurements. Because of its simplicity, the model allows for direct interrogation of the physical mechanisms responsible for this optimum. In particular, it isolates precisely how the follower's wing kinematics interact with the leader's wake to enhance aerodynamic efficiency. The model predicts an 11% reduction in total mechanical power for a follower in formation flight -- consistent with experimental estimates -- and shows that this saving arises from reductions in both induced and profile power, dominated by decreased profile power enabled primarily through reduced flapping amplitude and, secondarily, reduced upstroke flexion. These results provide a mechanistic explanation for the structure of V-formations and offer new insight into the aerodynamic principles governing collective flight.
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I know that following a hashtag is part of the Mastodon protocol itself, but since I'm in @… the majority of the time - it feels like it would be cool to:
- Offer a "follow for a week" / month option
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mechanism (maybe the ask part is configurable? maybe the client could also just handle it when next it runs?)
I hit this time and time again for moment in time events where during the thick of it, I'm invested and interested - conferences, world news, etc - but after which there's no more signal in the hashtag and it's just detritus putting load on a server somewhere.
Ideally this is something that should be in the protocol itself, but it feels like similar to quote replies that @… could bring a better user experience in advance of adoption of something like that

Entangled Encounters: Material and Social Transformations of Religious Communities in Europe https://relcfp.com/cfp/religion/europe/migration/2026/02/18/entangled-encounters/

Entangled Encounters: Material and Social Transformations of Religious Communities in Europe
Since the turn of the millennium, migration to Europe has significantly increased. Individuals have come to this continent often fleeing conflict and political instability as well as seeking improved social and economic wellbeing. For migrants, engagement in religious practice is a key resource in the post-migration period. Religious activities and infrastructure offer practical and spiritual support, as well as being a source of social belonging for newly arriving migrants. These factors often…

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Entangled Encounters: Material and Social Transformations of Religious Communities in Europe https://relcfp.com/cfp/religion/europe/migration/2026/02/18/entangled-encounters/

Entangled Encounters: Material and Social Transformations of Religious Communities in Europe
Since the turn of the millennium, migration to Europe has significantly increased. Individuals have come to this continent often fleeing conflict and political instability as well as seeking improved social and economic wellbeing. For migrants, engagement in religious practice is a key resource in the post-migration period. Religious activities and infrastructure offer practical and spiritual support, as well as being a source of social belonging for newly arriving migrants. These factors often…

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Welcome Frost writes tiny runes on windows in the north, while far south, cicadas tremble the air and ripe fruit perfumes the shade. It all feels measured, like a held breath. This week shares that feeling of poised energy. We track power. A 25 year solar plus storage pact in

Entangled Encounters: Material and Social Transformations of Religious Communities in Europe #acrel #Religidons #AARSBL

Entangled Encounters: Material and Social Transformations of Religious Communities in Europe
Since the turn of the millennium, migration to Europe has significantly increased. Individuals have come to this continent often fleeing conflict and political instability as well as seeking improved social and economic wellbeing. For migrants, engagement in religious practice is a key resource in the post-migration period. Religious activities and infrastructure offer practical and spiritual support, as well as being a source of social belonging for newly arriving migrants. These factors often…

Entangled Encounters: Material and Social Transformations of Religious Communities in Europe
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Since the turn of the millennium, migration to Europe has significantly increased. Individuals have…
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Entangled Encounters: Material and Social Transformations of Religious Communities in Europe
Since the turn of the millennium, migration to Europe has significantly increased. Individuals have come to this continent often fleeing conflict and political instability as well as seeking improved social and economic wellbeing. For migrants, engagement in religious practice is a key resource in the post-migration period. Religious activities and infrastructure offer practical and spiritual support, as well as being a source of social belonging for newly arriving migrants. These factors often…