Analyses of Victorian hog deer (axis porcinus) checking station data: demographics, body condition and time of harvest

This report looks into the sustainability and health of deer within Victoria\u27s regional areas. Hog Deer (Axis porcinus) are a popular and highly valued game species in Victoria, with licensed hunters permitted to harvest one male and one female during an annual hunting season during the month of April. All harvested deer must be tagged and presented at a checking station within 24 hours of harvest. A variety of morphological and biological data are recorded for each harvested animal during inspection at the checking stations. The objectives of this study were to (i) summarise biological data collected for all Hog Deer inspected at the four mainland checking stations during 1997–2011 (i.e. excluding Sunday Island, which is owned and managed by the Para Park Co-operative Game Reserve Limited), and (ii) provide recommendations for improving the usefulness of future data collection. A total of 1122 deer were presented at the mainland checking stations (70.4% male; 29.6% female) during 1997–2011, with annual totals ranging from 38 in 1999 to 111 in 2011. There was little evidence that the number or sex ratio of deer harvested annually changed substantially over the course of the study period. The overall percentages of deer harvested on public (52%) and private (48%) land also did not show any discernable trend during the study period. The ages of deer (estimated by molar eruption and tooth wear) ranged from 1 to 12 years for females and males. Although the age structures differed slightly for females and males, there was no evidence that this changed over the study period, although inconsistent recording of ages limited the opportunity for quantitative analyses of these data

Multilevel Analysis of Locomotion in Immature Preparations Suggests Innovative Strategies to Reactivate Stepping after Spinal Cord Injury

Locomotion is one of the most complex motor behaviors. Locomotor patterns change during early life, reflecting development of numerous peripheral and hierarchically organized central structures. Among them, the spinal cord is of particular interest since it houses the central pattern generator (CPG) for locomotion. This main command center is capable of eliciting and coordinating complex series of rhythmic neural signals sent to motoneurons and to corresponding target-muscles for basic locomotor activity. For a long-time, the CPG has been considered a black box. In recent years, complementary insights from in vitro and in vivo animal models have contributed significantly to a better understanding of its constituents, properties and ways to recover locomotion after a spinal cord injury (SCI). This review discusses key findings made by comparing the results of in vitro isolated spinal cord preparations and spinal-transected in vivo models from neonatal animals. Pharmacological, electrical, and sensory stimulation approaches largely used to further understand CPG function may also soon become therapeutic tools for potent CPG reactivation and locomotor movement induction in persons with SCI or developmental neuromuscular disorder

Metachronal waves in the flagellar beating of Volvox and their hydrodynamic origin.

Groups of eukaryotic cilia and flagella are capable of coordinating their beating over large scales, routinely exhibiting collective dynamics in the form of metachronal waves. The origin of this behavior--possibly influenced by both mechanical interactions and direct biological regulation--is poorly understood, in large part due to a lack of quantitative experimental studies. Here we characterize in detail flagellar coordination on the surface of the multicellular alga Volvox carteri, an emerging model organism for flagellar dynamics. Our studies reveal for the first time that the average metachronal coordination observed is punctuated by periodic phase defects during which synchrony is partial and limited to specific groups of cells. A minimal model of hydrodynamically coupled oscillators can reproduce semi-quantitatively the characteristics of the average metachronal dynamics, and the emergence of defects. We systematically study the model's behaviour by assessing the effect of changing intrinsic rotor characteristics, including oscillator stiffness and the nature of their internal driving force, as well as their geometric properties and spatial arrangement. Our results suggest that metachronal coordination follows from deformations in the oscillators' limit cycles induced by hydrodynamic stresses, and that defects result from sufficiently steep local biases in the oscillators' intrinsic frequencies. Additionally, we find that random variations in the intrinsic rotor frequencies increase the robustness of the average properties of the emergent metachronal waves.This work was supported in part by the EPSRC (M.P.), ERC Advanced Investigator grant 247333 and a Senior Investigator Award from the Wellcome Trust.This is the final version. It was first published by Royal Society Publishing at http://rsif.royalsocietypublishing.org/content/12/108/20141358

Long-range interactions, wobbles, and phase defects in chains of model cilia

Eukaryotic cilia and flagella are chemo-mechanical oscillators capable of generating long-range coordinated motions known as metachronal waves. Pair synchronization is a fundamental requirement for these collective dynamics, but it is generally not sufficient for collective phase-locking, chiefly due to the effect of long-range interactions. Here we explore experimentally and numerically a minimal model for a ciliated surface: hydrodynamically coupled oscillators rotating above a no-slip plane. Increasing their distance from the wall profoundly affects the global dynamics, due to variations in hydrodynamic interaction range. The array undergoes a transition from a traveling wave to either a steady chevron pattern or one punctuated by periodic phase defects. Within the transition between these regimes the system displays behavior reminiscent of chimera states

A rapid non-destructive DNA extraction method for insects and other arthropods

Preparation of arthropods for morphological identification often damages or destroys DNA within the specimen. Conversely, DNA extraction methods often destroy the external physical characteristics essential for morphological identification. We have developed a rapid, simple and non-destructive DNA extraction technique for arthropod specimens. This technique was tested on four arthropod orders, using specimens that were fresh, preserved by air drying, stored in ethanol, or collected with sticky or propylene glycol traps. The technique could be completed in twenty minutes for Coleoptera, Diptera and Hemiptera, and two minutes for the subclass Acarina, without significant distortion, discolouration, or other damage to the specimens