We examine the problem of snake-like locomotion by studying a system consisting of a planar inextensible elastic rod with adjustable spontaneous curvature, which provides an internal actuation mechanism that mimics muscular action in a snake. Using a Cosserat model, we derive the equations of motion in two special cases: one in which the rod can only move along a prescribed curve, and one in wh...

In the evolution of aspiration breathing, the responsibility for lung ventilation gradually shifted from the hyobranchial to the axial musculoskeletal system, with axial muscles taking over exhalation first, at the base of Tetrapoda, and then inhalation as well at the base of Amniota. This shift from hyobranchial to axial breathing freed the tongue and head to adapt to more diverse feeding styl...

Species interactions play a critical role in biological invasions. For example, exotic plant and microbe mutualists can facilitate each other's spread as they co-invade novel ranges. Environmental context may influence the effect of mutualisms on invasions in heterogeneous environments, however these effects are poorly understood. We examined the mutualism between the legume, Medicago polymorph...

Specialization in plant host-symbiont-soil interactions may help mediate plant adaptation to edaphic stress. Our previous field study showed ecological evidence for host-symbiont specificity between serpentine and non-serpentine adapted ecotypes of Collinsia sparsiflora and arbuscular mycorrrhizal fungi (AMF). To test for adapted plant ecotype-AMF specificity between C. sparsiflora ecotypes and...

Serpentine soils impose physiological stresses that limit plant establishment and diversity. The degree to which serpentine soils entail constraints on other organisms is, however, poorly understood. Here, I investigate the effect of serpentine soils on ectomycorrhizal (ECM) fungi by conducting a reciprocal transplant experiment, where serpentine and nonserpentine ECM fungal communities were cu...

This is the further research on delayed half-center oscillator (DHCO) neural system presented in our previous paper (Song and Xu Nonlinear Dyn 108:2595–2609, 2022. https://doi.org/10.1007/s11071-022-07222-y ). The DHCO used to construct a CPG (central pattern generator) control locomotion of snake-like robot with pitch-yaw connecting configuration. To this end, we firstly give an improved model...

In this work, the dispersive effect of low molecular weight sodium polyacrylate (PAAS) on serpentine, and its dispersion mechanism were systematically investigated through zeta potential measurements, micro and batch flotation as well as adsorption tests. At pH 5, where flotation of iron sulphide was routinely performed, pyrite and serpentine minerals were oppositely charged, and therefore they...

Serpentine soil generates distinct plant assemblages, but it is not known how this edaphically extreme environment affects arbuscular mycorrhizal fungal (AMF) assembly or how this may contribute to plant adaptation to serpentine. Our previous studies showed that serpentine and non-serpentine adapted ecotypes of Collinisa sparsiflora associates with distinct AMF assemblages, but a common garden ...

Among snakes four main types of terrestrial progression have been described: (i) serpentine movement which is observable in all, or nearly all, genera; (ii) concertina movement as briefly described by Wiedemann (1932) in Viper a and Coronella; (iii) crotaline or 'side-winding' as seen in Crotalus or Cerastes (Mosauer, 19320,6); and (iv) rectilinear movement as exhibited by boas and other large ...

Although plant adaptation to serpentine soils has been studied for several decades, the mechanisms of plant adaptation to edaphic extremes are still poorly understood. Arbuscular mycorrhizal fungi (AMF) are common root symbionts that can increase the plant hosts' establishment and growth in stressful environments. However, little is known about the role plant-AMF interactions play in plant adap...