This study provides the first focused investigation of rudist bivalves from the Upper Cretaceous of the Gulf Coastal Plain (GCP) in the southern US and previously undescribed specimens from the Flor de Alba Limestone Member of the Pozas Formation in Puerto Rico. Identified rudists from the GCP comprise the Monopleuridae, including Gyropleura, as well as Radiolitidae, including Biradiolites cardenasensi, Durania maxima, Guanacastea jamaicensis, Radiolites acutocostata, and Sauvagesia. Integrating rudist occurrences within well-established GCP biostratigraphy allows for extension of upper ranges of D. maxima and R. acutocostata into the late Campanian, and extension of the lower ranges of B. cardenasensis and G. jamaicensis into the early Campanian. Identified rudists from Puerto Rico comprise the Hippuritidae and include Barrettia monilifera, which supports the age of the Flor de Alba Limestone Member of the Pozas Formation as middle Campanian. Combined taxonomic, biostratigraphic, and paleobiogeographic analyses indicate there is no rudist fauna endemic to the GCP, and the region marks the northeastern range of the Caribbean genera Biradiolites, Durania, Guanacastea, Gyropleura, Radiolites, and Sauvagesia during the Campanian and Maastrichtian. The new occurrences help inform future updates of Late Cretaceous sea surface-current reconstructions for the Caribbean and Western Interior Seaway, USA.

The ability of dairy cows to discriminate between floors with a smooth epoxy resin surface or with surface-applied bauxite aggregates of mean diameters 0.5 mm, 1.2 mm or 2.5 mm (having coefficients of static friction of 0.35, 0.42, 0.49 and 0.74, respectively) was recorded when they were offered the opportunity to walk down paired floor surfaces to receive a food reward. Following training, one half of the cows were rewarded when they selected the floor with the greater friction and the other half were rewarded when they selected the floor with the least friction. The cows were able to distinguish between the different floor surfaces — even between surfaces with 0.5 mm and 1.2 mm aggregates, which humans found difficult to distinguish. Eight similar cows were then offered a choice of walking down passageways of paired floors with an equal reward at the end of each passageway. There were no consistent preferences for floor type, and when the reward was offered only on the side least favoured by each cow in the initial test, the random pattern of selection was still evident. A final choice test offered the cows the opportunity to traverse passageways of either wet concrete or concrete covered with excreta. All cows avoided the passageway with excreta completely, even when the reward was increased in this passageway and removed from the wet concrete passageway. This avoidance was attributed to the cows’ lack of contact with slurry, as they were at pasture for most of the day, in contrast to the cows used in previous work, which were housed in buildings with passageways covered in excreta and showed little avoidance behaviour of such passageways.

Guidelines for the housing of dairy cows do not address the provision of supplementary lighting in passageways, other than for inspection of the animals. Two experiments were conducted to investigate whether lighting passageways to various intensities influenced the locomotion of dairy cows. The first experiment compared the locomotion of dairy cows in a dark or lighted passageway as they walked back to their accommodation from milking. When the passageway was dark, the cows took shorter but more rapid steps - which probably increased their stability. In the second experiment, cows walked down a cubicle passageway to receive a food reward, with the light intensity in the building varying from 0-250 lux. Step length and stepping rate were recorded, as well as the angles of the cows’ leg joints (which were measured from video recordings). Once again, the cows increased their stepping rate in the dark, and this resulted in an increased walking rate, perhaps because they wished to return more rapidly to other members of their group and found the darkness aversive. In addition, the arcs of travel of the metacarpophalangeal joint and of the fore- and hindfeet angles to the floor were reduced in the dark, probably increasing the cows’ stability, and were greatest at 119 lux. The slowest walking rate was observed at 39 lux. Hence, the optimum illumination for dairy cow locomotion may lie approximately between 39 and 119 lux, as measured by our technique.

We conclude that during locomotion in dark passageways cows have to modify their walking behaviour significantly, so that the provision of at least a low level of lighting is desirable at night.

An experiment is described where 40 spring-calving dairy cows were allocated to be housed in a deep straw yard or a cubicle house from November to April, in order to examine the effects on behaviour, milk production and hoof health. Cows in straw yards spent longer lying down and feeding, except during oestrus when they increased their time spent standing proportionately more than cows in cubicles. In the straw yard cows spent longer in associative behaviour during oestrus and had fewer unsuccessful mounting attempts. There were no differences in milk production or composition but cows in the straw yard lost more weight after calving. Cows in the cubicles had a reduction in heel depth, which is a predisposing factor to lameness. It is concluded that a straw yard system for dairy cows allows greater opportunity to display normal behaviour, leads to better hoof health and provides acceptable levels of production.

Both the presence of slurry and dark conditions may deter dairy cows from using passageways in cubicle accommodation, thus restricting movement and normal behaviour. We attempted to train seven dairy cows to recognize the quantity of reward offered in a transparent tube containing molasses in a Y-maze. Only one cow failed to consistently select the aisle containing the larger reward. The cows were then individually offered the choice of traversing either a passageway with a 5cm-depth of cow excreta or a clean, dry passageway to collect their rewards. The quantity of the rewards on the two sides was varied between zero and 400ml of molasses to determine the price that the cows were prepared to pay for entering the aisle with excreta. Only two of the seven cows showed a clear avoidance of the passageway with excreta. There was a tendency (P < 0.1) for the cows to avoid the passageway with excreta only when it contained no reward and the clean passageway contained a reward of 400ml molasses. Otherwise, there was no clear avoidance of the passageway with excreta. We also investigated whether cows preferred to enter a lighted or unlighted passageway. All the cows, except one, showed a strong avoidance of the dark passage, even when it contained the largest reward and the lighted passage contained no reward. We conclude that dairy cows demonstrate only mild avoidance of passageways with excreta but strongly avoid passageways without lighting. Therefore, we suggest that passageways for dairy cows should be lit at all times.

Animals under human management are often separated from conspecifics, which may lead to behaviour indicative of separation distress or grief. For the purposes of this paper, grief is considered as a biological response to separation, indicated by a bi-phasic ‘protest-despair’ behavioural response. It is reasonable to assume that only animals which are able to form complex social bonds can experience grief. Scientific experiments have suggested that some farm and laboratory animals experience distress or grief as a result of maternal separation and social isolation. However, little is known about whether the public believe that animals are capable of grief. Therefore, we surveyed 1,000 members of the public to establish what knowledge they have about grief in animals and to compare this to what we know in science. The survey revealed that 90% of the general public believed that some or all animals can experience grief, with 23% believing that all animals can grieve. They attributed grief more to companion animals and animals with higher level cognitive abilities than to farm animals and animals that may be feared. It is concluded that public belief about grief in animals extends beyond scientific evidence, and that educating people about scientific findings and management practices connected with grief and separation distress may improve the welfare of farm and laboratory animals.

Horseshoe crabs as a group are renowned for their morphological conservatism punctuated by marked shifts in morphology associated with the occupation of non-marine environments and have been suggested to exhibit a consistent developmental trajectory throughout their evolutionary history. Here, we report a new species of horseshoe crab from the Ordovician (Late Sandbian) of Kingston, Ontario, Canada, from juvenile and adult material. This new species provides critical insight into the ontogeny and morphology of the earliest horseshoe crabs, indicating that at least some Palaeozoic forms had freely articulating tergites anterior to the fused thoracetron and an opisthosoma comprising 13 segments.

We present the most sensitive and detailed view of the neutral hydrogen ( ${\rm H\small I}$ ) emission associated with the Small Magellanic Cloud (SMC), through the combination of data from the Australian Square Kilometre Array Pathfinder (ASKAP) and Parkes (Murriyang), as part of the Galactic Australian Square Kilometre Array Pathfinder (GASKAP) pilot survey. These GASKAP-HI pilot observations, for the first time, reveal ${\rm H\small I}$ in the SMC on similar physical scales as other important tracers of the interstellar medium, such as molecular gas and dust. The resultant image cube possesses an rms noise level of 1.1 K ( $1.6\,\mathrm{mJy\ beam}^{-1}$ ) $\mathrm{per}\ 0.98\,\mathrm{km\ s}^{-1}$ spectral channel with an angular resolution of $30^{\prime\prime}$ ( ${\sim}10\,\mathrm{pc}$ ). We discuss the calibration scheme and the custom imaging pipeline that utilises a joint deconvolution approach, efficiently distributed across a computing cluster, to accurately recover the emission extending across the entire ${\sim}25\,\mathrm{deg}^2$ field-of-view. We provide an overview of the data products and characterise several aspects including the noise properties as a function of angular resolution and the represented spatial scales by deriving the global transfer function over the full spectral range. A preliminary spatial power spectrum analysis on individual spectral channels reveals that the power law nature of the density distribution extends down to scales of 10 pc. We highlight the scientific potential of these data by comparing the properties of an outflowing high-velocity cloud with previous ASKAP+Parkes ${\rm H\small I}$ test observations.

The Variables and Slow Transients Survey (VAST) on the Australian Square Kilometre Array Pathfinder (ASKAP) is designed to detect highly variable and transient radio sources on timescales from 5 s to $\sim\!5$ yr. In this paper, we present the survey description, observation strategy and initial results from the VAST Phase I Pilot Survey. This pilot survey consists of $\sim\!162$ h of observations conducted at a central frequency of 888 MHz between 2019 August and 2020 August, with a typical rms sensitivity of $0.24\ \mathrm{mJy\ beam}^{-1}$ and angular resolution of $12-20$ arcseconds. There are 113 fields, each of which was observed for 12 min integration time, with between 5 and 13 repeats, with cadences between 1 day and 8 months. The total area of the pilot survey footprint is 5 131 square degrees, covering six distinct regions of the sky. An initial search of two of these regions, totalling 1 646 square degrees, revealed 28 highly variable and/or transient sources. Seven of these are known pulsars, including the millisecond pulsar J2039–5617. Another seven are stars, four of which have no previously reported radio detection (SCR J0533–4257, LEHPM 2-783, UCAC3 89–412162 and 2MASS J22414436–6119311). Of the remaining 14 sources, two are active galactic nuclei, six are associated with galaxies and the other six have no multi-wavelength counterparts and are yet to be identified.

It is increasingly common for models of shallow-layer overland flows to include equations for the evolution of the underlying bed (morphodynamics) and the motion of an associated sedimentary phase. We investigate the linear stability properties of these systems in considerable generality. Naive formulations of the morphodynamics, featuring exchange of sediment between a well-mixed suspended load and the bed, lead to mathematically ill-posed governing equations. This is traced to a singularity in the linearised system at Froude number ${\textit {Fr}} = 1$ that causes unbounded unstable growth of short-wavelength disturbances. The inclusion of neglected physical processes can restore well posedness. Turbulent momentum diffusion (eddy viscosity) and a suitably parametrised bed load sediment transport are shown separately to be sufficient in this regard. However, we demonstrate that such models typically inherit an associated instability that is absent from non-morphodynamic settings. Implications of our analyses are considered for simple generic closures, including a drag law that switches between fluid and granular behaviour, depending on the sediment concentration. Steady morphodynamic flows bifurcate into two states: dilute flows, which are stable at low ${\textit {Fr}}$, and concentrated flows which are always unstable to disturbances in concentration. By computing the growth rates of linear modes across a wide region of parameter space, we examine in detail the effects of specific model parameters including the choices of sediment erodibility, eddy viscosity and bed load flux. These analyses may be used to inform the ongoing development of operational models in engineering and geosciences.

In this paper, we describe the system design and capabilities of the Australian Square Kilometre Array Pathfinder (ASKAP) radio telescope at the conclusion of its construction project and commencement of science operations. ASKAP is one of the first radio telescopes to deploy phased array feed (PAF) technology on a large scale, giving it an instantaneous field of view that covers $31\,\textrm{deg}^{2}$ at $800\,\textrm{MHz}$. As a two-dimensional array of 36$\times$12 m antennas, with baselines ranging from 22 m to 6 km, ASKAP also has excellent snapshot imaging capability and 10 arcsec resolution. This, combined with 288 MHz of instantaneous bandwidth and a unique third axis of rotation on each antenna, gives ASKAP the capability to create high dynamic range images of large sky areas very quickly. It is an excellent telescope for surveys between 700 and $1800\,\textrm{MHz}$ and is expected to facilitate great advances in our understanding of galaxy formation, cosmology, and radio transients while opening new parameter space for discovery of the unknown.

High dietary phosphorus (P), particularly soluble salts, may contribute to chronic kidney disease development in cats. The aim of the present study was to assess the safety of P supplied at 1 g/1000 kcal (4184kJ) from a highly soluble P salt in P-rich dry format feline diets. Seventy-five healthy adult cats (n 25/group) were fed either a low P control (1·4 g/1000 kcal [4184kJ]; Ca:P ratio 0·97) or one of two test diets with 4 g/1000 kcal (4184 kJ); Ca:P 1·04 or 5 g/1000 kcal (4184kJ); Ca:P 1·27, both incorporating 1 g/1000 kcal (4184 kJ) sodium tripolyphosphate (STPP) – for a period of 30 weeks in a randomised parallel-group study. Health markers in blood and urine, glomerular filtration rate, renal ultrasound and bone density were assessed at baseline and at regular time points. At the end of the test period, responses following transition to a commercial diet (total P – 2·34 g/1000 kcal [4184kJ], Ca:P 1·3) for a 4-week washout period were also assessed. No adverse effects on general, kidney or bone (skeletal) function and health were observed. P and Ca balance, some serum biochemistry parameters and regulatory hormones were increased in cats fed test diets from week 2 onwards (P ≤ 0·05). Data from the washout period suggest that increased serum creatinine and urea values observed in the two test diet groups were influenced by dietary differences during the test period, and not indicative of changes in renal function. The present data suggest no observed adverse effect level for feline diets containing 1 g P/1000 kcal (4184 kJ) from STPP and total P level of up to 5 g/1000 kcal (4184 kJ) when fed for 30 weeks.

The Rapid ASKAP Continuum Survey (RACS) is the first large-area survey to be conducted with the full 36-antenna Australian Square Kilometre Array Pathfinder (ASKAP) telescope. RACS will provide a shallow model of the ASKAP sky that will aid the calibration of future deep ASKAP surveys. RACS will cover the whole sky visible from the ASKAP site in Western Australia and will cover the full ASKAP band of 700–1800 MHz. The RACS images are generally deeper than the existing NRAO VLA Sky Survey and Sydney University Molonglo Sky Survey radio surveys and have better spatial resolution. All RACS survey products will be public, including radio images (with $\sim$ 15 arcsec resolution) and catalogues of about three million source components with spectral index and polarisation information. In this paper, we present a description of the RACS survey and the first data release of 903 images covering the sky south of declination $+41^\circ$ made over a 288-MHz band centred at 887.5 MHz.