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Sex‐specific reproductive roles contribute to sexual dimorphic morphological trait variations. In uniparental mouth‐brooding fishes, the mouth performs a reproductive function in addition to its key roles in feeding and respiration, resulting in the potential for sex‐specific functional performance trade‐offs. Trait differences related to parental care may occur when the individual matures or be restricted to periods when the parent is mouth‐brooding. This study explored sexual dimorphism and morphological trait adaptations related to feeding, breeding, respiration and locomotion performance in two paternal mouth‐brooding freshwater fishes (Glossamia aprion and Neoarius graeffei). Eight morphological traits were evaluated for sexual dimorphism (non‐brooder males vs. females) and male breeding state differences (brooders vs. non‐brooders). Male breeding state was a significant predictor of trait variation in both species. Brooders differed in buccal volume and in several feeding and locomotory traits compared to non‐brooder males. Non‐brooder males had bigger buccal volumes and relative eye diameters (G. aprion) and larger relative gape sizes (N. graeffei) compared to females, a potential response to both mouth‐brooding and feeding requirements. Although there were clear trait differences between brooder and non‐brooder males, further research is required to confirm whether individuals return to their former morphology once mouth‐brooding has ceased or if trait differences are maintained post‐brooding. This study highlights the importance of considering the potential impacts of intraspecific trait variation on the performance of critical life functions, such as feeding, respiration and locomotion across the life history. [ABSTRACT FROM AUTHOR]

The genus Wakaleo represents a close outgroup to the charismatic marsupial hypercarnivore Thylacoleo carnifex. While early species of Wakaleo were likely arboreal, or at least scansorial, the ecology of later species of Wakaleo is not well understood. Here we present descriptions of new postcranial material of W. vanderleueri and W. alcootaensis from mid- and late-Miocene fossil deposits from the Australian Northern Territory. New calculations suggest that these taxa were smaller than previously thought, around 30 kg and 50 kg respectively. The postcrania reveal increasing adaptation towards terrestrial locomotion and felid-like grappling predation within this lineage, in contrast to the more canid-like adaptations occurring at around the same time in the other major group of terrestrial marsupial carnivores, the thylacinids. This hypothesis seems to reflect similar patterns of divergent morphological adaptation towards large carnivorous forms among placental mammals, and highlights a greater diversity in the evolutionary history of medium to large sized marsupial carnivores during the Miocene in Australia than previously recognized. [ABSTRACT FROM AUTHOR]

Recreational trampling damage of natural vegetation is an increasing problem in the global context and has the potential to impact on vegetation communities that are of high ecological and socio-economic interest. Wildflower tourism in the national parks of southwest Australia, a global biodiversity hotspot, has the potential to damage the flora on which it depends through trampling. Little research has been previously undertaken in these largely shrub-dominated communities to identify and quantify such impacts. This study is the first to do so, using observational studies of tourists, a descriptive study, and trampling experiments. The behaviours of independent tourists and tour groups were observed. Of the 213 independent visitors observed 41 visitors left trails to view flowers and in the process trampled vegetation. Vegetation height and cover were measured at three sites frequented by wildflower tourists. Vegetation height and cover declined in response to use by tourists. Trampling experiments, which relied on trampling treatments of 0, 30, 100, 200, 300/500 passes, where 0 passes represents the control, were applied at four sites. Trampling led to a significant reduction in vegetation height immediately post-treatment, for all treatments, with a non-significant recovery over time. Trampling also significantly reduced vegetation cover, with the resistance indices for these experimental sites ranging from 30 to 300 passes. Collectively these results illustrate the low resilience and resistance of these valued communities and the possible impacts of wildflower and other nature based tourism, through trampling. The paper concludes with suggested management strategies, which strongly emphasise the importance of education for the tourism industry and provide for international comparisons in regard to recreational trampling impacts on biodiverse shrub land communities. [ABSTRACT FROM AUTHOR]

Cane toads ( Bufo marinus) are now moving about 5 times faster through tropical Australia than they did a half-century ago, during the early phases of toad invasion. Radio-tracking has revealed higher daily rates of displacement by toads at the invasion front compared to those from long-colonised areas: toads from frontal populations follow straighter paths, move more often, and move further per displacement than do toads from older (long-established) populations. Are these higher movement rates of invasion-front toads associated with modified locomotor performance (e.g. speed, endurance)? In an outdoor raceway, toads collected from the invasion front had similar speeds, but threefold greater endurance, compared to conspecifics collected from a long-established population. Thus, increased daily displacement in invasion-front toads does not appear to be driven by changes in locomotor speed. Instead, increased dispersal is associated with higher endurance, suggesting that invasion-front toads tend to spend more time moving than do their less dispersive conspecifics. Whether this increased endurance is a cause or consequence of behavioural shifts associated with rapid dispersal is unclear. Nonetheless, shifts in endurance between frontal and core populations of this invasive species point to the complex panoply of traits affected by selection for increased dispersal ability on expanding population fronts. [ABSTRACT FROM AUTHOR]

Irregular and unpredictable day-to-day patterns in locomotor activity are often observed in animal movement patterns. While ecological processes may drive some variability in activity, underlying rhythms may modulate activity patterns independently of exogenous factors. We investigated multiple day (infradian) locomotor activity rhythms, in long-term continuous records of individual daily step counts, in a natural population of the Australian sleepy lizard Tiliqua rugosa. We examined temporal periodicity in locomotor activity using spectral analysis of sequential, overlapping 12-day windows of activity data. Lizards were inactive on average 1 day in 6, independent of ambient temperature, and showed infradian locomotor activity rhythms. In a drought year, 2002/2003, rhythms did not exceed randomized activity patterns. In an average rainfall year, 2003/2004, 6 and 2-day cycles occurred significantly more often than by chance. Individuals normally moved independently of conspecifics, although there was some short-term synchrony of activity rhythms. Rainfall did not consistently produce a synchronized pulse of activity in the population. We propose individually based rhythms, associated with differing optimal thermoregulatory requirements for foraging and digestion. In studies of population ecology, individual activity rhythms may explain day-to-day variation in encounter rates. [ABSTRACT FROM AUTHOR]

Little Penguins, Eudyptula minor, breed in several small colonies in New Zealand and Australia. In this study, we compare the birds’ diving performances at different sites situated throughout their breeding range. Environmental conditions and breeding success vary drastically amongst colonies, but all birds feed on similar types of prey and face similar limitations on their foraging range. We examined several diving parameters and calculated the proportion of foraging zone available during breeding to examine whether oceanographic and geographic factors in the foraging zone can explain variations in diving behaviour and fledging success among the different colonies. In colonies with high fledging success, Penguin Island and Oamaru, penguins made shallow dives <50 m depth and had lower diving effort. More than 90% of the foraging zone was in waters <50 m depth in these colonies. Motuara Island also has shallow waters with 95% <50 m depth, but the fledging success was low. Phillip Island has only 42% of waters <50 m and comparatively low fledging success. Thus, penguins dived deeper and showed a higher diving effort in colonies with lower fledging success (Motuara Island and Phillip Island), indicating that they were disadvantaged compared to conspecifics from other colonies that dived shallower and with a lesser diving effort. We concluded that bathymetry is an important factor, but not the only one, which influences fledging success. [ABSTRACT FROM AUTHOR]

The development of righting was studied in the young of Dasyurus hallucatus, a small marsupial from northern Australia. Young were tested from birth to weaning. Righting began at 40 days, when tactile input on the snout triggered rotation to prone. Over the next 15-20 days, asymmetrical tactile input on the body triggered righting movements by the hindlegs (and later by the forelegs). Vestibular righting reflexes developed after these tactile righting reflexes. Furthermore, asymmetrical vestibular righting (i.e., when the young are held laterally in the air) developed before symmetrical vestibular righting (i.e., when held downward by the pelvis or placed supine in water). Vestibular righting triggered by falling supine in the air did not develop until about 80 days. This study further demonstrates that righting behavior does not consist of a single, integrated motor pattern, but a suite of motor patterns having independent control mechanisms and patterns of development. [ABSTRACT FROM AUTHOR]