Neighbour and environmental influences on the growth patterns of two temperate Haliclonid sponges

2008 ◽  
Vol 59 (4) ◽  
pp. 304 ◽  
Author(s):  
D. A. Abdo ◽  
J. I. McDonald ◽  
E. S. Harvey ◽  
J. Fromont ◽  
G. A. Kendrick
Keyword(s):  
Environmental Conditions ◽  
Growth Pattern ◽  
Growth Dynamics ◽  
Growth Patterns ◽  
Sponge Species ◽  
Bioactive Metabolites ◽  
Seasonal Growth ◽  
Adverse Environmental Conditions ◽  
Potential Exploitation ◽  
Important Habitat

Understanding the growth dynamics of an organism is central to understanding its ecology and biology. Sponges often dominate many subtidal habitats, however, determining their growth dynamics is often difficult owing to the plastic and amorphous morphologies that occur in many species. Two sympatric Haliclonid sponge species were examined using a novel photogrammetric technique to understand how environmental and competitive influences affect their growth. Sponges of both species were tagged and monitored over a 14-month period. Haliclona sp. 1 (green Haliclona) showed little variation in growth compared with Haliclona sp. 2 (brown Haliclona), which had a significant seasonal growth pattern. Both green and brown Haliclona grew a significant amount over the period of study (green Haliclona: 3.4% month–1; brown Haliclona: 6.0% month–1 (with neighbours) and 4.1% month–1 (without neighbours)). In both species, growth was not significantly influenced by competition from neighbours; rather, neighbouring organisms appeared to provide protection from adverse environmental conditions. The growth dynamics of both species have important implications for the maintenance of both species populations, particularly given the important habitat they provide for other organisms, and their potential exploitation for the supply of bioactive metabolites.

Comparison of selected Douglas-fir seed sources for cambial and leader growth patterns in four western Oregon environments

1977 ◽  
Vol 7 (1) ◽  
pp. 154-164 ◽  
Author(s):  
William H. Emmingham
Keyword(s):  
Growth Rate ◽  
British Columbia ◽  
Growth Pattern ◽  
Douglas Fir ◽  
Growth Patterns ◽  
Seasonal Growth ◽  
Growth Duration ◽  
Cambial Growth ◽  
Seed Sources ◽  
Definite Pattern

The leader and cambial growth of sapling Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) from both inland and coastal varieties followed a definite pattern in four western Oregon environments. Generally, buds became active first and cambial growth became active soon after. Leader growth stopped in August, long before cambial growth, which continued into October. Phenology, total seasonal growth, and growth pattern for trees from coastal sources from Vancouver Island, B.C., to southern Oregon were more similar than for trees from inland sources from British Columbia to Idaho and Arizona. Most of the differences among populations in one season's growth were related to growth rate rather than growth duration.

CREATION OF THE INDUCED APPLE-THREE TETRAPLOIDS

1970 ◽  
pp. 23-25
Author(s):  
L. V. Tashmatova ◽  
О. V. Mantseva ◽  
N. V. Gorbacheva
Keyword(s):  
Environmental Conditions ◽  
Selection Process ◽  
Normal Growth ◽  
Cytological Analysis ◽  
Open Pollination ◽  
Apple Breeding ◽  
Adverse Environmental Conditions ◽  
Diploid Gametes ◽  
Resistance To Diseases

The basic moments of a process of obtaining apple tetraploids as donors of diploid gametes for apple breeding with polyploidy using are demonstrated. In industrial terms, triploids are of the greatest importance. The manifested effect of heterosis leads to the improvement of many characteristics - higher resistance to diseases, pests and adverse environmental conditions, greater autogamy than in diploids, less pronounced periodicity of fruiting, larger fruits and a convenient crown for harvesting. Triploids are developed as a result of crosses 2n × 3n or 2n × 4n. Tetraploids are necessary for more successful apple breeding with polyploidy using. For industry they are not of great importance but they are of interest as donors of diploid non-reduced gametes and allow to make the selection process more directional. One of the methods of experimental polyploidy is the induction of polyploids using mutagenes. The germs were treated with colchicines at concentrations 0.1% - 0.4% during 24 and 48 hours. According to the morphology the obtained plants were divided into five groups. Colchicine concentrations 0.3% and 0.4% during 48 hours of the treatment had a disastrous impact on the development of germs. As a result of the cytological analysis, tetraploids and chimeras were revealed, which were obtained from the seeds from the open pollination of Orlik and Svezhest (treatment variants – 0,1% colchicines solution and 24 and 48 hours of exposition), as well as from the seeds obtained as a result of the Svezhest × Bolotovskoye crossing. Tetraploids had a normal growth but they differed in large leaves, while chimeras were of low size with normal leaves and internodes.

scholarly journals Production performance of cows raised with different post-weaning growth patterns

2021 ◽  
Author(s):  
Harvey C Freetly ◽  
Robert A Cushman ◽  
Gary L Bennett
Keyword(s):  
Growth Pattern ◽  
Bos Taurus ◽  
Life Time ◽  
Growth Patterns ◽  
Production Performance ◽  
Genetic Population ◽  
Breed Type ◽  
Genetic Types ◽  
Period 2 ◽  
Step Growth

Abstract The period of heifer development is a relatively small fraction of a cow’s life; however, her pattern of growth may have permanent effects on her productivity as a cow. We hypothesized that altering the growth pattern during the peri-pubertal period would increase life-time productivity across genetic types of Bos taurus cows. The objective was to determine the stayability, calf production, and weight of calf weaned across six calf crops. Heifers (n = 685) were placed on one of two developmental programs at 256 ± 1 d of age. Control heifers received a diet that provided 228 kcal ME·(BW, kg) -0.75 daily, and Stair-Step heifers were allocated 157 kcal ME·(BW, kg) -0.75 daily for 84 or 85 d, and then the daily allocation was increased to 277 kcal ME·(BW, kg) -0.75. Stair-Step heifers (0.33 ± 0.02 kg/d) had a lower ADG than Control heifers (0.78 ± 0.02 kg/d; P < 0.001) during Period 1, and Stair-Step heifers (0.93 ± 0.03 kg/d) had a greater ADG than Controls (0.70 ± 0.03 kg/d; P < 0.001) during Period 2. There were no treatment (P = 0.28) or breed type differences (P = 0.42) for the proportion of cows weaning a calf; however, the proportion of cows weaning a calf decreased with cow age (P < 0.001). Calves from Stair-Step dams had heavier weaning weights (193 ± 1 kg) compared to Control calves (191 ± 1 kg; P = 0.007). There was not a treatment (P = 0.25) or breed type differences in cumulative BW weaned (P = 0.59). A diverse genetic population of cattle within Bos taurus was tested and responses in calf production did not differ between Stair-Step growth pattern and a more constant non-obese growth pattern.

The lambing period of mountain sheep: synthesis, hypotheses, and tests

1982 ◽  
Vol 60 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Fred L. Bunnell
Keyword(s):  
Body Weight ◽  
Thermal Stress ◽  
Weight Gain ◽  
Female Body ◽  
Extreme Environments ◽  
Growth Patterns ◽  
Central Tendency ◽  
Seasonal Growth ◽  
Early Weight Gain ◽  
Definition Of

Data on lambing periods from 30 populations of North American mountain sheep are reviewed. Among all populations lambing begins later and duration is shorter at more northern altitudes (p < 0.00006). Correlations are enhanced (p < 0.00003) when latitude is replaced by a phenological index incorporating altitude. Termination of lambing is not correlated with latitude or with phenological index. Two broad patterns are evident. Populations feeding on vegetation of less predictable growth patterns ("desert type") have lengthy lambing seasons; populations feeding on vegetation exhibiting more predictable growth patterns ("alpine type") have shorter lambing seasons, typically two oestrous cycles in length. Definition of "types" by latitude or sheep taxonomy reveals significant differences in lambing periods, but correlations are enhanced when "types" are defined on the basis of habitat.Among taxa, birth weights are correlated with female body weight (rs = 0.87). Birth weights are heavier in extreme environments, seasonal growth patterns are expressed better in the alpine type, and early weight gain is most rapid in the northernmost subspecies. All populations show a strong central tendency with regard to peak lambing (17 May ± 6.8 days). Departures from that tendency respond more to predictability of vegetation than to thermal stress or predation pressure.

Age validation and seasonal growth patterns of a subtropical marsh fish: The Gulf Killifish, Fundulus grandis

2017 ◽  
Vol 100 (10) ◽  
pp. 1315-1327 ◽  
Author(s):  
Anthony R. Vastano ◽  
Kenneth W. Able ◽  
Olaf P. Jensen ◽  
Paola C. López-Duarte ◽  
Charles W. Martin ◽  
...  
Keyword(s):  
Growth Patterns ◽  
Seasonal Growth ◽  
Age Validation ◽  
Fundulus Grandis

The Effects of Adverse Environmental Conditions on Workload

1975 ◽  
Vol 19 (3) ◽  
pp. 301-304
Author(s):  
Ann E. Martin
Keyword(s):  
Environmental Conditions ◽  
Environmental Variables ◽  
Secondary Task ◽  
The Other ◽  
Random Numbers ◽  
Performance Decrement ◽  
Experimental Conditions ◽  
Continuous Noise ◽  
Adverse Environmental Conditions ◽  
Intermittent Noise

The present study was conducted to investigate the effects of environmental conditions on visual workload. The environmental variables used were temperature, studied at levels of 45°F., WBGT, and 95°F., WBGT; and noise, studied at 83 dBA intermittent noise and 93 dBA continuous noise. Workload was defined as the amount of attention demanded from an operator as measured by performance decrement on a secondary task while performing a primary and secondary task simultaneously. The secondary task was reading random numbers, and the primary task was reading word lists. Significant differences (p<.05) were found between the control condition and all experimental conditions. The low temperature and high temperature-continuous noise conditions were significantly different from the other conditions. Noise and temperature were found to significantly increase workload (p<05).

scholarly journals Influence of Vertical Facial Growth Pattern on Herbst Appliance Effects in Prepubertal Patients: A Retrospective Controlled Study

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Maria Rita Giuca ◽  
Marco Pasini ◽  
Sara Drago ◽  
Leonardo Del Corso ◽  
Arianna Vanni ◽  
...  
Keyword(s):  
Growth Pattern ◽  
Class Ii ◽  
Growth Patterns ◽  
Response To Treatment ◽  
Controlled Study ◽  
Class Ii Malocclusion ◽  
Facial Growth ◽  
Herbst Appliance ◽  
Lateral Cephalograms ◽  
Vertical Growth Pattern

Introduction. The Herbst device is widely used for correction of class II malocclusions; however, most of the researches carried out on the Herbst appliance in literature do not take into account patients with a different mandibular divergence. The aim of this study was to investigate the effects of Herbst on dental and skeletal structures and to evaluate possible influence of vertical facial growth patterns. Methods. A retrospective study was conducted on lateral cephalograms of 75 growing patients (mean age: 9.9 ± 1.9 years) with class II malocclusion treated with Herbst. Subjects were divided into 3 groups using the mandibular divergence index (SN and GoMe angle). Cephalometric parameters were evaluated using the modified SO (sagittal occlusion) Pancherz’s analysis. A statistical analysis was conducted to evaluate differences among groups using ANOVA. Results. Our study showed differences in response to treatment depending on patient’s facial vertical growth pattern. Cranial base angle and mandibular rotation were significantly different (p<0.05) between hypodivergent patients and normodivergent patients and between hypodivergent and hyperdivergent subjects. Conclusion. Hypodivergent patients increased their mandibular divergence during treatment to a greater extent than normodivergents; moreover, hyperdivergent patients exhibited a decreased mandibular divergence at the end of the treatment.

Sign in / Sign up

Export Citation Format

Share Document