Flying the North American Adirondack whitetail on instruments: A multi-parameter modeling approach to ecosystem-based wildlife management

We compare ecosystem-based wildlife management to instrument flight of aircraft. Airplanes cannot be controlled without visual ground reference, or if this is impossible to a cluster of flight instruments. Instrument pilots are trained to develop a rhythmic scan of the cluster to monitor and correct flight path and attitude. The untrained tendency is to fixate on a single gauge. Then, the aircraft deviates from its desired attitude and trajectory, and control may be lost. Fixation is like single-factor management wherein variables like habitat quality, recruitment, predator control, or harvest rates are singled out for adjustment without considering the others.

Ungulate populations are no less complex than aircraft in flight. They are multifactorial and move through time and space. To be managed effectively they must be guided in these movements through the monitoring and control instruments nature has provided. These are not necessarily proximate because populations are embedded in ecosystems and cannot be isolated from systemic complexity. Holistic management is needed, which requires a suite of monitoring and control parameters analogous to those in instrument flight.

We hold that every institution serving the interests of wise resource use should employ comprehensive, large-scale, ecosystem-based models built, tested, and perfected as a committed institutional activity over long periods of time. We call this Institutionalized Model-Making (IMM), and see models drawn from the collective expertise of scientists and their data in the same relation to nature as flight simulators are to actual aircraft. They mimic responses to control actions, and enable training in multifactorial management analogous to the instrument scans and control actions of the instrument pilot.

A model comprehensive enough for institutional use has not been built. We call attention to our efforts to develop such a model at the Huntington Wildlife Forest in New York's Adirondack Mountains. This is a model of the North American whitetail deer (Odocoileus virginianus Miller). It is too complex and incomplete for use in this paper, so a smaller-scale model is employed to make the case. In simulation trials parameters are ranked as to control sensitivity, then manipulated singly and multiply to demonstrate the superiority of the multiparameter approach.     

MAINTENANCE OR LOSS OF GENETIC VARIATION UNDER SEXUAL AND PARENTAL ANTAGONISM AT A SEX-LINKED LOCUS

An intralocus genetic conflict occurs when a locus is selected in opposing directions in different subsets of a population. Populations with two sexes have the potential to host a pair of distinct intralocus conflicts: sexual antagonism and parental antagonism. In this article, we examine the population genetic consequences of these conflicts for X-linked genes. Both conflicts are capable of maintaining genetic variation in a population, but to different degrees. For weak sexual antagonism, the X chromosome has a higher opportunity for polymorphism than the autosomes. For parental antagonism, there is a very limited opportunity for polymorphism on the X chromosome relative to autosomes or to sexual antagonism. X-linkage introduces an asymmetry in the inheritance and expression of sexually and parentally antagonistic genes that leads to a biased fixation of alleles with certain effects. We find little support for the commonly held intuition that the X chromosome should be biased toward fixing female-beneficial alleles. Contrary to this intuition, we find that the X chromosome is biased toward fixation of male-beneficial alleles for much of the range of dominance. Additionally, we find that the X chromosome is more favorable to the fixation of alleles that are beneficial when maternally derived.     

Overexpression of hns in the plant growth‐promoting bacterium Enterobacter cloacae UW5 increases root colonization

Aims: Plant growth‐promoting rhizobacteria (PGPR) introduced into soil often do not compete effectively with indigenous micro‐organisms for plant colonization. The aim of this study was to identify novel genes that are important for root colonization by the PGPR Enterobacter cloacae UW5. Methods and Results: A library of transposon mutants of Ent. cloacae UW5 was screened for mutants with altered ability to colonize canola roots using a thermal asymmetric interlaced (TAIL)‐PCR‐based approach. A PCR fragment from one mutant was reproducibly amplified at greater levels from genomic DNA extracted from mutant pools recovered from seedling roots 6 days after seed inoculation compared to that from the cognate inoculum cultures. Competition assays confirmed that the purified mutant designated Ent. cloacae J28 outcompetes the wild‐type strain on roots but not in liquid cultures. In Ent. cloacae J28, the transposon is inserted upstream of the hns gene. Quantitative RT‐PCR showed that transposon insertion increased expression of hns on roots. Conclusions: These results indicate that increased expression of hns in Ent. cloacae enhances competitive colonization of roots. Significance and Impact of the Study: A better understanding of the genes involved in plant colonization will contribute to the development of PGPR that can compete more effectively in agricultural soils.     

PGC-1β regulates angiogenesis in skeletal muscle

Patients who experience acute ischemic stroke may develop hyperglycemia, even in the absence of diabetes, but the exact mechanisms are still unclear. Adipose tissue secretes numerous proinflammatory cytokines and is involved in the regulation of glucose metabolism. This study aimed to determine the effects of acute stroke on adipose inflammatory cytokine expression. In addition, because sympathetic activity is activated after acute stroke and catecholamines can regulate the expression of several adipocytokines, this study also evaluated whether alterations in adipose proinflammatory cytokines following acute stroke, if any, were medicated by sympathetic system. Acute ischemic brain injury was induced by ligating the right middle cerebral artery and bilateral common carotid arteries in male adult Sprague-Dawley rats. Adipose tumor necrosis factor-α (TNF-α) and monocyte chemoattractant protein-1 (MCP-1) mRNA and protein levels were determined by RT-PCR and enzyme-linked immunoassay, respectively. The stroke rats developed glucose intolerance on days 1 and 2 after cerebral ischemic injury. The fasting blood insulin levels and insulin resistance index measured by homeostasis model assessment were higher in the stroke rats compared with the sham group. Epididymal adipose TNF-α and MCP-1 mRNA and protein levels were elevated one- to twofold, in association with increased macrophage infiltration into the adipose tissue. When the rats were treated with a nonselective β-adrenergic receptor blocker, propranolol, before induction of cerebral ischemic injury, the acute stroke-induced increase in TNF-α and MCP-1 was blocked, and fasting blood insulin concentration and homeostasis model assessment-insulin resistance were decreased. These results suggest a potential role of adipose proinflammatory cytokines induced by the sympathetic nervous system in the pathogenesis of glucose metabolic disorder in rats with acute ischemic stroke.     

PHOTOREACTIONS OF PARTIALLY BLINDED WHIP-TAIL SCORPIONS

The experiments dealt with in this paper were devised to ascertain (1) the relative effectiveness as photoreceptors of the whip-tail scorpion''s median eyes, lateral eye groups, and cutaneous sensitive areas, and (2) the effect on orientation produced by symmetrical and by asymmetrical interference with the photoreceptive mechanism. Each of the receptors was eliminated unilaterally and bilaterally, singly and in combinations with other receptors. In all, sixteen different abnormal conditions of the photoreceptive apparatus were produced. The reactions of animals thus partially blinded were measured in terms of angular deflection from an initial path of locomotion. Measurements obtained under anterior, lateral, and bilaterally balanced illumination were compared with measurements made on normal animals under the same conditions of illumination. The change from the normal reaction induced by covering a photoreceptor was taken as an index of the effectiveness of the receptor prevented from functioning. By comparing the values of the changes from normal reactions produced by the elimination of the several receptors, their relative effectiveness is approximated as median eyes : lateral eyes : cutaneous sensitive areas :: 1:1.6:2.2. All animals in which the receptive mechanism was rendered functionally asymmetrical exhibited, when subJected to bilaterally balanced illumination, deflections toward the side which had been made less sensitive. In a series of measurements made on animals in ten different conditions of asymmetry the amplitudes of the deflections were proportional to the degree of unbalance which had been produced in the photosensitive mechanism. Animals in which the receptive mechanism was reduced but left in a symmetrical condition maintained an undisturbed balance of reaction when subjected to equal, opposed lights. Under lateral or anterior illumination the rate of attaining a new direction of orientation was reduced in proportion to the extent of the interference with the receptive mechanism. The reactions of symmetrically and asymmetrically blinded scorpions indicate that orientation is attained and maintained by a transmission of impulses to the muscles of locomotion which is proportional bilaterally to the excitation of the symmetrically located photoreceptors. In their effect on orientation the three pairs of receptors are completely coordinated. Orientation depends upon bringing the excitation of the receptive mechanism as a whole into bilateral equilibrium.