Dormancy in the land snail, Helicella virgata (Pulminata : Helicidae)

1968 ◽  
Vol 16 (5) ◽  
pp. 857 ◽  
Author(s):  
DE Pomeroy
Keyword(s):  
Ambient Temperature ◽  
Evaporative Cooling ◽  
South Australia ◽  
Land Snail ◽  
The Sun ◽  
Winter Dormancy ◽  
Dormant State ◽  
The Family

H. virgata and other introduced snails of the family Helicidae spend much of their time in a dormant state. In winter, dormancy usually occurs daily, and lasts for a few hours only. In summer, when rainfall is rare, it may last for many days or even weeks, and is then referred to as aestivation. H. virgata aestivates in conspicuous positions, often fully exposed to the sun, at heights of up to 11 m from the ground. No appreciable heat is lost by evaporative cooling, and the temperatures of dormant snails may exceed the ambient temperature by as much as 10 degC, the amount of the excess being a function of height above the ground. Estimates are given of the temperatures experienced by aestivating snails over a whole summer; these exceed 30�C for three-quarters of the summer, and 40�C is reached quite commonly. The positions where H. virgata aestivate are discussed in relation to temperature, and it is concluded that their behaviour, which presumably evolved in their native European range, is less appropriate in the climate of South Australia; but despite this, their populations reach high densities in places.

Some aspects of the ecology of the land snail, Helicella virgata, in South Australia

1969 ◽  
Vol 17 (3) ◽  
pp. 495 ◽  
Author(s):  
DE Pomeroy
Keyword(s):  
Natural History ◽  
Natural Population ◽  
South Australia ◽  
Growth Curves ◽  
Land Snail ◽  
Food Resources ◽  
Winter Dormancy ◽  
Rate Of Growth ◽  
Length Of Life

H. virgata was introduced to South Australia from Europe and has since become remarkably numerous. Its natural history is described, including breeding, growth, and food. There is normally one generation per year, the eggs mostly hatching in autumn and the young growing rapidly until spring. Marking and recapture were used to determine growth curves in the field. Snails are only active when the ground is moist and the humidity high. Even in winter dormancy is frequent, and in summer it is prolonged. H. virgata is microphagous, feeding mainly on the topsoil and surface litter, avoiding places from which these are removed. It was shown experimentally that the numbers of young produced, their rate of growth, and the length of life of adults all decreased with increasing density. This was explained in terms of increasing starvation. A natural population was studied for nearly 2 years. In places the density of this population was high and there was evidence of a consequent shortage of food, which affected young and adults differently. "Effective fecundity" (p. 509) was inversely proportional to the density of the population. There were marked aggregations, apparently reflecting the distribution of food. However, the degree of "patchiness" (Lloyd 1967) remained fairly constant with time. Over most of its range H. virgata is relatively scarce and the numbers in these places are less likely to press upon the food resources. The effects of cultivation and trampling, lack of calcium in the soil, and other factors must explain this scarcity. Weather can certainly be important; the drought of 1965-66 reduced all populations severely.

Correction of two homonyms and an original spelling of Thach [2018]

2019 ◽  
Vol 29 (1) ◽  
pp. 75-76
Author(s):  
Barna Páll-Gergely
Keyword(s):  
Land Snail ◽  
The Family

Two substitution names are proposed for primary homonyms introduced for land snail of the family Camaenidae in Thach [2018].

scholarly journals Avaliação de Tratamentos de Superação de Dormência em Sementes do Delonix regia (Boger ex Hook.) Raf coletadas no Horto Florestal Tote Garcia, Cuiabá, Mato Grosso

2017 ◽  
Vol 21 (1) ◽  
pp. 48
Author(s):  
Ana Carolina Amorim Marques ◽  
Osvaldo Borges Pinto Junior ◽  
Vera Lucia Lopes Vieira
Keyword(s):  
Ambient Temperature ◽  
Thermal Shock ◽  
Environmental Conditions ◽  
Economic Value ◽  
Mato Grosso ◽  
Delonix Regia ◽  
Breaking Dormancy ◽  
Manual Counting ◽  
The Family ◽  
Temperature Water

A árvore Delonix regia (flamboyant) pertence à família Fabaceae, subfamília Caesalpinioideae, originário da ilha de Madagascar. Tem potencial valor econômico ornamental, pois se trata de uma espécie extremamente florífera e exuberante, indicada para programas de arborização, como parques, praças e jardins, sendo inadequada para ruas e avenidas, devido a suas raízes serem caracterizadas como superficiais. Essa espécie exótica, adaptada as condições ambientais de clima tropical, tem porte de 10 – 12m de altura, de tronco volumoso, espesso, com raízes tabulares. Por apresentar características de dormência tegumentar, este trabalho teve objetivo de avaliar alguns tratamentos para superação de dormência das sementes do Delonix regia. O experimento foi do tipo quantitativo, em que as sementes foram submetidas a três tratamentos e uma testemunha, em um total de 4 tratamentos, com 75 sementes cada. A emergência foi observada in locu, por meio de contagem manual. Os tratamentos utilizados foram: escarificação mecânica com lixa (n° 120); imersão em água em temperatura ambiente por 72 horas, choque térmico com imersão das sementes em água a 80 ºC por 05 min e a testemunha em que não houve nenhuma intervenção. Observou-se que a escarificação mecânica e o choque térmico proporcionaram os melhores resultados para superação de dormência das sementes do Delonix regia.Palavras-chave: Paisagismo. Dormência. Emergência.AbstractThe tree Delonix regia (flamboyant) belongs to the family Fabaceae, subfamily Caesalpinioideae, originally from the island of Madagascar. It has the potential ornamental economic value, because it is an extremely floriferous and exuberant species suitable for reforestations programs such as parks,and gardens, being inappropriate for streets and avenues, because its roots are characterized as superficial. This exotic species, adapted to the environmental conditions of tropical climate, reaches size of 10-12 m tall, large trunk, dense with tabular roots. It is renowned for being an extremely floriferous and exuberant species. By presenting cutaneous numbness characteristics, the objective of this study was to evaluate some treatments to overcome dormancy of seeds Delonix regia. The experiment was the quantitative type, in which the seeds were subjectedto three treatments and a control, a total of 4 treatments with 75 seeds each. The emergence was observed in locus through manual counting. The treatments were mechanical scarification with sandpaper (#120); immersion in ambient temperature water for 72 hours, thermal shock deep soaking the seeds in water at 80 °C for 5 minutes and the control, which had no intervention. It was observed that the mechanical scarification and thermal shock provided the best results for breaking dormancy of seeds Delonix regia.Keywords: Landscaping. Emergency Seedling. Dormancy

P1943Ambient temperature and seasonal effects on blood pressure in 2.6 million Australians

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
E Atkins ◽  
Q Pilard ◽  
K Rogers ◽  
A Salam ◽  
A Rodgers
Keyword(s):  
Blood Pressure ◽  
Seasonal Variation ◽  
Ambient Temperature ◽  
Medication Use ◽  
South Australia ◽  
Seasonal Effects ◽  
Lipid Lowering ◽  
Maximum Temperature ◽  
History Of ◽  
The Mean

Abstract Background There is evidence that blood pressure (BP) levels vary considerably from season to season, due principally to variation in ambient temperature. This gives the potential for both under- and over-treatment if BP lowering medications are not varied seasonally, but is not acknowledged in clinical guidelines. We will describe the seasonal variation in BP and assess the association between systolic blood pressure (SBP) and outdoor maximum ambient temperature in Australia. Methods The primary care data is an extract from MedicineInsight, a national general practice data program developed and managed by NPS MedicineWise, which extracts deidentified data from almost 10% of all Australian general practices. We included patients aged 30–90 years with at least one BP measure recorded from 1 Jan 2010 to 1 Aug 2017. Australian Bureau of Meteorology daily max temperature is linked by matching observation dates and location to nearest weather station. Decomposition of the mean will determine seasonal variation. Multiple linear regression was used to estimate the associations between max temperature and SBP with adjustment for age, sex, socioeconomic index, current smoking, comorbidities, BP lowering medication use, lipid lowering medication use and year of BP measurement. Results The study population includes 2.6 million people, mean age 55 years (standard deviation [SD] 16.3). Fifty-five percent are female, over a third of the cohort reside in New South Wales, and 62.4% reside in major Australian cities. The mean (SD) temperature was 23°C (6.6). There was a mean (SD) of 7 (11.4) BP measurements per person over the study period, median 3 measures (interquartile range 1–8). A quarter had a history of hypertension, 8% had a history of cardiovascular disease, and 8% had a history of diabetes. Twenty-six percent had at least one prescription for BP lowering therapy. The average monthly SBP for the cohort demonstrated strong seasonal variation with higher values in winter. The population mean varies by 3mmHg SBP between seasons across Australia, ranging from 1.7mmHg in the Northern Territory to 3.5mmHg in South Australia (range of mean maximum temperature 3°C [30–33] and 14°C [15–29] for the capital cities respectively). Each 10°C increase in max outdoor temperature was associated with a 1.8mmHg [95% CI 1.80–1.83] lower mean SBP. The proportion of people with SBP>140mmHg varied by season, irrespective of age, sex and use of BP lowering treatment. For example, among those treated control rates varied between 70 and 81%, and among those not treated between 78 and 85% (Figure). Blood pressure seasonality in Australia Conclusions BP control rates vary considerably by season. These findings have implications for the reliable diagnosis of hypertension, and suggest seasonal adjustments in treatment should be considered for some patients. The clinical and public health relevance of this phenomenon is expected to increase with increasing climate variability. Acknowledgement/Funding National Health and Medical Research Council Australia, National Heart Foundation Australia

Thermal sweating in different body regions of sheep

1979 ◽  
Vol 92 (2) ◽  
pp. 511-512 ◽  
Author(s):  
A. K. Rai ◽  
B. S. Mehta ◽  
M. Singh
Keyword(s):  
Thermal Stress ◽  
Ambient Temperature ◽  
Heat Loss ◽  
Evaporative Cooling ◽  
Sweat Glands ◽  
Evaporative Heat Loss ◽  
Body Regions ◽  
Time Period ◽  
Sweat Production ◽  
Thermal Sweating

Although sheep combat thermal stress mainly by panting, a sizeable amount (40%) of total evaporative heat loss, is from sources other than panting (Hales & Brown, 1974). The frequency of sporadic discharge of sweat glands increases with increase in ambient temperature and is accompanied by a decline in respiration rate (Bligh, 1961). The wool coat can reduce evaporative cooling but sweating may have cooling value in sheep breeds with open fleeces (Rai, Singh & More, 1978). In sheep, the number and size of the sweat glands (Waites & Voglmayr, 1962) and the quantum of sweat production in a particular time period (Ghoshal et al. 1977) varies in different body regions. In view of the possible significance of surface evaporative cooling, thermal sweating in different body regions of sheep was investigated.

Rainfall in the Negev Desert during the Middle Holocene, Based on 13C of Organic Matter in Land Snail Shells

1990 ◽  
Vol 34 (2) ◽  
pp. 186-197 ◽  
Author(s):  
Glenn A. Goodfriend
Keyword(s):  
Organic Matter ◽  
Transition Zone ◽  
Plant Communities ◽  
Stable Carbon Isotope ◽  
Land Snail ◽  
Land Snails ◽  
Negev Desert ◽  
Annual Rainfall ◽  
Middle Holocene ◽  
The Family

AbstractAnalysis of stable carbon isotope ratios (13C/12C) of organic matter in land snail shells is used to infer middle Holocene rainfall amounts in the Negev Desert by reconstructing the distribution of C4 plants in the family Chenopodiaceae. The organics are derived from the diet of the snails, which consists of plant material, and are enriched in 13C where C4 plants are present. A survey of modern plant communities indicates that in areas receiving ≥300 mm mean annual rainfall, nearly all plant communities consist of C3 species only (no C4 chenopodes), whereas in areas under ≤230 mm rainfall, most plant communities contain one or more C4 chenopode species. In between is a transition zone consisting of a mosaic of both pure C3 and mixed C3 + C4 plant communities. Isotopic results for fossil land snails indicate a consistent geographic pattern throughout the middle Holocene, from ca. 6500 to 3000 yr B.P., with the transition zone located ca. 20 km south of its present position. This implies a near doubling of rainfall within this region as compared to present.

Gordon Roy Cameron, 1899-1966

1968 ◽  
Vol 14 ◽  
pp. 83-116
Keyword(s):  
Small Town ◽  
South Australia ◽  
Growing Up ◽  
Hill Country ◽  
The Bible ◽  
Murray River ◽  
The Family ◽  
The Government ◽  
Opening Up

Gordon Roy Cameron was born in Australia on 30 June 1899 at Echuca, a small town on the Victoria side of one of the bends on the Murray River. His father, George Cameron, was then a Methodist minister at a small village called Wamboota. George Cameron’s parents (Grandfather Cameron and his wife, earlier a Miss Miller) who came of hard-working farming stock in Dyce, Aberdeenshire, with forbears in Inverness and Fort Augustus, had left Aberdeen for Australia the day after their marriage early in the 1870’s and taken up land in Minlaton in St Vincent’s peninsula, South Australia. They had eleven children, of whom George Cameron was the eldest; he seems to have had a hard life on the farm. When he was twelve years old the Government of Victoria began opening up the Mallee area in northern Victoria, and he and his father each drove a wagon containing members of the family and their few goods over the 500 miles trek—much of it over uncleared scrub, desert and hill country—from Minlaton to the Mallee area, where they took up about a hundred acres of scrub to make a farm, later extended to some two thousand acres. There they and their neighbours built the mud house that still survived in 1920. Some fourteen years later the farm was going well, the younger children were growing up, and George Cameron, who had recently taken part in Bible Christian services and had developed a reputation as a local preacher, decided to join the Bible Christians as a candidate for the Ministry. In due course he was appointed to a circuit as a probationer in Horsham, North Victoria, where he met Emily Pascoe, whom he later married.

scholarly journals John Henry Gaddum, 1900-1965

1967 ◽  
Vol 13 ◽  
pp. 56-77 ◽  
Keyword(s):  
Natural History ◽  
The Sun ◽  
Modern History ◽  
Maternal Grandfather ◽  
The Family ◽  
Justice Of The Peace ◽  
General Strike

John Henry Gaddum was born on 31 March 1900 in Hale, Cheshire, the eldest child of Henry Edwin Gaddum and Phyllis Mary née Barratt. He had three brothers and two sisters. His father was a silk importer whose main energies were devoted to charitable work in Manchester, where he was a Justice of the Peace, and Chairman of many of the leading charitable committees. He got them all together in a house which was later called Gaddum House. Manchester University honoured him by giving him an honorary M.A. About his father, Gaddum wrote: ‘As the eldest I got more help from him than did the rest of the family. He made me fond of riding and natural history, and taught me to use my hands. He constructed a large sundial which was also a summer house, and which told the correct time to within about a minute at all times of the year—making due allowance for the apparent irregularities of the sun at different times of the year. It also told the day of the year. He was fond of sketching and taught me to draw— but not very successfully. He made me fond of long walks in Wales and Switzerland, and of swimming and sailing.’ John Gaddum’s maternal grandfather, Alfred Barratt, was, as Gaddum wrote, a clever man. He went from Rugby to Balliol, Oxford, under Jowett, and there achieved what was then a record in examinations: a double first in Moderations followed by First Class in Classics, Mathematics and Modern History. He wrote two books on philosophy and died young (35). A first cousin of Gaddum’s mother was Sir Samuel Hoare, later Lord Templewood, at one time Foreign Secretary and Ambassador to Spain. Another first cousin of his mother was Dick Acland, who was Bishop of Bombay and by whom he was married. A first cousin of his father, Grace Joynson, married William Hicks, who became Lord Brentford and who was Home Secretary at the time of the General Strike in 1926.

scholarly journals ‘Childness’: An Alternative Approach to the Archaeology of Childhood through Cemetery Studies

Religions ◽  
2019 ◽  
Vol 10 (8) ◽  
pp. 451
Author(s):  
Muller ◽  
Burke ◽  
Leiuen ◽  
Degner ◽  
Farrell
Keyword(s):  
South Australia ◽  
Social Contexts ◽  
Social Processes ◽  
Rural South ◽  
Social Ideology ◽  
Alternative Approach ◽  
The Social ◽  
The Family ◽  
Using Data ◽  
Class And Status

Notions of childhood in colonial Australia were informed by a variety of social contexts that varied across time and space and were given material expression in the memorialization of children’s burials. Using data drawn from two studies of nineteenth-century cemeteries in rural South Australia, in this paper, we suggest an alternative way to understand children archaeologically that avoids the trap of essentialism: the notion of ‘childness’. Childness is defined as the multiple conceptions of being, and being labeled, a child. The concept of being a child may be instantiated in different ways according to particular social, cultural, chronological, and religious contexts; childness is the measure of this variation. In Western historical settings, the most likely causes for such variation are the social processes of class and status via the closely associated ideologies of gentility and respectability and their attendant expectations around labor, as well as the shifts they represent in the social ideology of the family. Exploring childness, rather than children, provides an alternative way to approach the histories of contemporary Western understandings of childhood, including when particular types of childhood began and ended, and according to what criteria in different contexts, as well as how boundaries between child and adult were continually being established and re-negotiated.

Two new genera and species of chiltoniid amphipods (Crustacea: Amphipoda: Talitroidea) from freshwater mound springs in South Australia

Zootaxa ◽  
2009 ◽  
Vol 2293 (1) ◽  
pp. 35-52 ◽  
Author(s):  
RACHAEL A. KING
Keyword(s):  
South Australia ◽  
Distinct Species ◽  
Morphological Characters ◽  
New Genera ◽  
Molecular Analyses ◽  
Australian Species ◽  
The Family ◽  
Freshwater Habitats ◽  
Australian Freshwater

Amphipods within the family Chiltoniidae are an abundant yet taxonomically poorly known member of Australian freshwater habitats. With only four species known from Australia, the group is inadequately defined and marked by taxonomists as difficult to identify. Recent molecular analyses of chiltoniids from mound springs in South Australia detected several distinct species, prompting a morphological revision of material from the central and southern Lake Eyre region. Clear groups defined by unique combinations of morphological characters (focusing on uropodal, coxal, male gnathopod 2, and antennal morphology) were found that closely correlated with clades found in the molecular analyses. Arabunnachiltonia n. gen. is established for A. murphyi n. sp. from Strangways Springs in South Australia. Wangiannachiltonia n. gen. is established for W. guzikae n. sp. from Davenport Springs in South Australia. The chiltoniid genera are discussed and a key is presented to the known Australian species.

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