Age-Dependent Mortality Rates of Some Common British Birds

1985 ◽  
pp. 275-288
Author(s):  
A. P. Dobson
Keyword(s):  
Mortality Rates ◽  
Age Dependent ◽  
Dependent Mortality

scholarly journals The influence of environmentally induced heterogeneity on age-specific genetic variance for mortality rates

2000 ◽  
Vol 75 (3) ◽  
pp. 321-329 ◽  
Author(s):  
SCOTT D. PLETCHER ◽  
JAMES W. CURTSINGER
Keyword(s):  
Drosophila Melanogaster ◽  
Sample Size ◽  
General Feature ◽  
Genetic Variance ◽  
General Trend ◽  
Mortality Rates ◽  
Parametric Models ◽  
Age Dependent ◽  
Biased Estimates ◽  
Existing Data

Using parametric models that describe the increase in mortality rates with age, we demonstrate that environmentally induced heterogeneity among genetically identical individuals is sufficient to generate biased estimates of age-specific genetic variance. Although the magnitude of the bias may change with age, one general trend emerges: the true genetic variance at the oldest ages is likely to be dramatically underestimated. Our results are robust to different manifestations of heterogeneity and suggest that such a bias is a general feature of these models. We note that age-dependent estimates of genetic variance for characters that are correlated with mortality (either genetically or environmentally) can be expected to be similarly affected. The results are independent of sample size and suggest that the bias may be more widespread in the literature than is currently appreciated. Our results are discussed with reference to existing data on mortality variance in Drosophila melanogaster.

Age-Dependent Effect of Foal Heat Breeding on Pregnancy and Embryo Mortality Rates in Thoroughbred Mares

2020 ◽  
Vol 90 ◽  
pp. 102982
Author(s):  
João Ricardo Malheiros de Souza ◽  
Paulo Bayard Dias Gonçalves ◽  
Kalyne Bertolin ◽  
Rogério Ferreira ◽  
Ana Sílvia Sardinha Ribeiro ◽  
...  
Keyword(s):  
Mortality Rates ◽  
Dependent Effect ◽  
Embryo Mortality ◽  
Age Dependent

The age structure of a striped maple population

1979 ◽  
Vol 9 (4) ◽  
pp. 504-508 ◽  
Author(s):  
David E. Hibbs
Keyword(s):  
Structure Analysis ◽  
High Mortality ◽  
Age Structure ◽  
Mortality Rates ◽  
Population Age Structure ◽  
Survivorship Curve ◽  
Age Dependent ◽  
Gap Phase ◽  
Annual Mortality

Cohort and population age structure analysis showed that, after the initially high mortality rates of the 1st year (87.5%), striped maple seedlings (Acerpensylvanicum L.) underwent practically no mortality until the age of 15. Annual mortality was up (3.8%) between the ages of 16 and 40, then dropped to a lower level (1.6%). Mortality was age dependent and generally density independent. The survivorship curve agrees well with a pattern that could be expected of a species whose strategy is gap phase replacement.

scholarly journals Forest responses to simulated elevated CO 2 under alternate hypotheses of size‐ and age‐dependent mortality

2020 ◽  
Vol 26 (10) ◽  
pp. 5734-5753 ◽  
Author(s):  
Jessica F. Needham ◽  
Jeffrey Chambers ◽  
Rosie Fisher ◽  
Ryan Knox ◽  
Charles D. Koven
Keyword(s):  
Age Dependent ◽  
Dependent Mortality

scholarly journals Assessing joint spatial autocorrelations between mortality rates due to cardiovascular conditions in South Africa

2019 ◽  
Vol 14 (2) ◽  
Author(s):  
Timotheus B. Darikwa ◽  
Samuel Manda ◽  
‘Maseka Lesaoana
Keyword(s):  
Heart Failure ◽  
South Africa ◽  
Heart Disease ◽  
Health Outcomes ◽  
Empirical Bayes ◽  
Spatial Clustering ◽  
Mortality Rates ◽  
Noncommunicable Diseases ◽  
Co Morbidity ◽  
Dependent Mortality

South Africa is experiencing an increasing burden of noncommunicable diseases (NCDs). There is evidence of co-morbidity of several NCDs at small geographical areas in the country. However, the extent to which this applies to joint spatial autocorrections of NCDs is not known. The objective of this study was to derive and quantify multivariate spatial autocorrections for NCDrelated mortality in South Africa. The study used mortality attributable to cerebrovascular, ischaemic heart failure and hypertension captured by the country’s Department of Home Affairs for the years 2001, 2007 and 2011. Both univariate and pairwise spatial clustering measures were derived using observed, empirical Bayes smoothed and age-adjusted standardised mortality rates. Cerebrovascular and ischaemic heart co-clustering was significant for the years 2001 and 2011. Cerebrovascular and hypertension co-clustering was significant for the years 2007 and 2011, while hypertension and ischaemic heart co-clustering was significant for the year 2011. Co-clusters of cerebrovascular-ischaemic heart disease are the most profound and located in the south-western part of the country. It was successfully demonstrated that bivariate spatial autocorrelations can be derived for spatially dependent mortality rates as exemplified by mortality rates attributed to three cardiovascular conditions. The identified co-clusters of spatially dependent health outcomes may be targeted for an integrated intervention and monitoring programme.

scholarly journals Age-Independent Adult Mortality in a Long-Lived Herb

Diversity ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 187 ◽  
Author(s):  
Edelfeldt ◽  
Lindell ◽  
Dahlgren
Keyword(s):  
General Pattern ◽  
Cost Of Reproduction ◽  
Mortality Rates ◽  
Adult Mortality ◽  
Trade Offs ◽  
Age Dependent ◽  
Annual Mortality ◽  
Age Independent ◽  
Long Term Studies

Relative to mammals and birds, little is known about the mortality trajectories of perennial plants, as there are few long-term demographic studies following multiple yearly cohorts from birth to death. This is particularly important because if reproductively mature individuals show actuarial senescence, current estimations of life spans assuming constant survival would be incorrect. There is also a lack of studies documenting how life history trade-offs and disturbance influence the mortality trajectories of plants. We conducted Bayesian survival trajectory analyses (BaSTA) of a 33-year individual-based dataset of Pulsatilla vulgaris ssp. gotlandica. Mortality trajectories corresponded to “Type III” survivorship patterns, with rapidly decreasing annual mortality rates for young plants, but with constant mortality for reproductively mature individuals. We found trade-off effects resulting in a cost of growth for non-reproductive plants but no apparent cost of reproduction. Contrarily to our expectation, young plants that had previously shrunk in size had a lower mortality. However, accounting for trade-offs and disturbance only had minor effects on the mortality trajectories. We conclude that BaSTA is a useful tool for assessing mortality patterns in plants if only partial age information is available. Furthermore, if constant mortality is a general pattern in polycarpic plants, long-term studies may not be necessary to assess their age-dependent demography.

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