Turtle Girdles: Comparing the Relationships Between Environment and Behavior on Forelimb Function in Loggerhead Sea Turtles (Caretta caretta) and River Cooters (Pseudemys concinna).

Locomotion in water and on land impose dramatically different demands, yet many animals successfully move in both environments. Most turtle species perform both aquatic and terrestrial locomotion but vary in how they use their limbs. Freshwater turtles use anteroposterior movements of the limbs during walking and swimming with contralateral fore- and hindlimbs moving in synchrony.

Buoyancy control and air breathing in royal knifefish (Chitala blanci) and a new hypothesis for the early evolution of vertebrate air-breathing behaviors.

We present the first description of inspiration-first air breaths in royal knifefish, Chitala blanci, a ray-finned fish known to use four-stroke air breaths. Four-stroke breaths are used by nearly all ray-finned fish species that use their gas bladder to breathe air and are the ancestral breath type of ray-finned fishes. Interestingly, one such species, Amia calva, is known to perform two distinct breath types.

Epaxial and hypaxial co-contraction: a mechanism for modulating strike pressure and accuracy during suction feeding in channel catfish.

Most fish species use concentric epaxial and hypaxial contractions to suction feed, whereby both muscle groups produce cranial expansion and negative intraoral pressures. In contrast, channel catfish (Ictalurus punctatus) suction feed with little to no cranial elevation and epaxial shortening, generating suction power primarily with hypaxial shortening and pectoral girdle retraction. We hypothesized that channel catfish (1) actively anchor the head via isometric contraction of the epaxials and (2) vary feeding performance by modulating the absolute and relative outputs of the co-contracting muscles.

How to become a strategic purchaser of rehabilitation services.

Rehabilitative care is often overlooked and underfunded despite being a key component of universal health coverage, and now faces further neglect due to indirect impacts of the coronavirus disease 2019 pandemic. Policy-makers can leverage strategic purchasing approaches to make the most of available funds and maximize health gains. To implement more strategic purchasing of rehabilitation, health planners must: (i) develop and prioritize evidence-based rehabilitation service packages; (ii) use fit-for-purpose contracting and provider payment mechanisms to incentivize quality and efficient service delivery; and (iii) strengthen stewardship.

Long-Axis Rotation of Jaws of Bamboo Sharks () During Suction Feeding.

Long-axis rotation (LAR) of the jaws may be an important component of vertebrate feeding mechanisms, as it has been hypothesized to occur during prey capture or food processing across diverse vertebrate groups including mammals, ray-finned fishes, and sharks and rays. LAR can affect tooth orientation as well as muscle fiber direction and therefore muscle power during feeding. However, to date only a handful of studies have demonstrated this LAR in vivo.