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Levels of deprivation amongst different ward of canterbury economics essay

A study of the role of kin in determining child survival and growth. Here we document differential patterns of kin support in a rural Ethiopian community where post-marital residence patterns provide differential access to relatives. Using demographic and anthropometric data collected from rural villages in Southern Ethiopia we are able to identify effects of presence of kin on child mortality and growth patterns.

Multivariate event history analyses and general linear models are used to control for the effects of age, sex, birth order, family size and socio-economic status. Additionally, time allocation data provide detailed information on the role of kin within the household. Mortality analyses indicate that presence of grandmothers had a positive effect on child survival. Maternal grandmothers had a particularly beneficial effect on child height, but paternal grandmothers less so.

Time allocation data suggest that grandmothers preferentially visited their daughters' households, irrespective of proximity and, when present, assisted their daughters in heavy domestic tasks rather than helping directly with grandchild care. Matrilocal post-marital residence was associated with improved child survival, but lower levels of child nutritional status low height and low weight for height. The negative effect of matrilocal residence on child nutritional status is interesting, since it contradicts the other positive findings of maternal kin.

This may be due to wealth effects, increased competition between siblings or higher survival of smaller infants in matrilocal households. Maternal care and child's survival in humans: These studies usually assume that offspring survival until maturity is independent of mothers' survival.

However, in humans, children's survival depends mainly on maternal care. Therefore we expect a strong relationship between mother's and child's survival in our species. In the present study, we investigate whether an increase of this latter relationship during human evolution i. Methods - We constructed two evolutionary scenarios modelling an increase of maternal care.

Evolutionary demography.

The first leads to an increase in children's mean survival until maturity. The second leads to a decrease in children's survival because of a higher level of child's altriciality children's survival is more dependent of maternal care. Perturbation analyses of the Finite Rate of Increase 1 were performed in both cases. Results - Both scenarios lead to an increase in lifespan even after menopauseto a higher fertility at the peak of reproductive life and to a decrease in fertility at the end of the reproductive life.

These features are the main characteristic of human life history. Furthermore, our model allows associations between features not expected in models assuming that children's survival is independent of mother's survival: Reproductive effort, immunosenescence and longevity in pre-industrial Finns Virpi Lummaa1, Samuli Helle2 and Jukka Jokela2 1University of Sheffield, 2University of Turku The trade-off between reproduction and longevity has been proposed to be mediated by the reproductive costs accelerating senescence of the immune system, leading to shorter lifespan.

These physiological costs should be buffered by the resources available for the mothers during pregnancy and lactation so that costs should be lower for mothers in good condition.

  • First, we found that mothers delivering twins had reduced post reproductive survival;
  • In contrast, longevity and disease mortality of men were independent of reproductive effort, suggesting that females carried higher costs of reproduction.

We used individual-based historical population records maintained by the Lutheran church to examine how increased reproductive effort delivery of twins vs. First, we found that mothers delivering twins had reduced post reproductive survival.

This effect arose because mothers of twins had a higher probability of succumbing to an infectious disease mainly tuberculosis than mothers delivering singletons only.

The risk was further elevated if these mothers had started their reproduction young.

  1. Results - Both scenarios lead to an increase in lifespan even after menopause , to a higher fertility at the peak of reproductive life and to a decrease in fertility at the end of the reproductive life. A study of the role of kin in determining child survival and growth.
  2. Furthermore, our model allows associations between features not expected in models assuming that children's survival is independent of mother's survival.
  3. Therefore we expect a strong relationship between mother's and child's survival in our species.

Second, we found evidence that production of physiologically more costly sons shortened maternal lifespan. The magnitude of this effect corresponds to a 34-week reduction in longevity per each son delivered. The number of delivered sons increased the probability of dying of an infectious disease among women living in resource-limited conditions low social classbut not in higher social classes.

  1. These features are the main characteristic of human life history.
  2. Therefore we expect a strong relationship between mother's and child's survival in our species. The negative effect of matrilocal residence on child nutritional status is interesting, since it contradicts the other positive findings of maternal kin.
  3. Perturbation analyses of the Finite Rate of Increase 1 were performed in both cases. These physiological costs should be buffered by the resources available for the mothers during pregnancy and lactation so that costs should be lower for mothers in good condition.
  4. Results - Both scenarios lead to an increase in lifespan even after menopause , to a higher fertility at the peak of reproductive life and to a decrease in fertility at the end of the reproductive life.
  5. These features are the main characteristic of human life history. The risk was further elevated if these mothers had started their reproduction young.

In contrast, longevity and disease mortality of men were independent of reproductive effort, suggesting that females carried higher costs of reproduction. Our results suggest that increased physiological cost of reproduction promoted immunosenescence in mothers living under limited resources.