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Chapman SN, Lummaa V. Grandmother effects over the Finnish demographic transition. Evol Hum Sci 2024; 6:e6. [PMID: 38516365 PMCID: PMC10955376 DOI: 10.1017/ehs.2023.36] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 11/30/2023] [Accepted: 12/15/2023] [Indexed: 03/23/2024] Open
Abstract
Demographic transitions are defining events for human societies, marking shifts from natural mortality and fertility rates to the low rates seen in industrialised populations. These transitions can affect trait evolution through altering the direction and strength of selection when variance in fertility and mortality decline. One key feature of human evolution is the evolution of extended post-reproductive life through indirect fitness benefits from grandmothering. Although studies in pre- and post-transition societies have documented beneficial grandmother presence, it remains unknown whether these associations changed before, during, or after the transition. Here, we use genealogical data from eighteenth- to twientieth-century Finland to show grandmother-associated changes of two measures of evolutionary fitness (grandchild survival and birth rate) over the transition. We find that grandmothers had greater opportunity to help as the transition progressed, but their effect on grandchild survival declined alongside general mortality rates, implying that selection on lifespan from grandmothering declined too. Whilst grandmother presence was still associated with reduced birth intervals and hence more grandchildren born post-transition, the nature of this relationship changed greatly. This suggests that although potential for intergenerational interactions increased over the demographic transition, the (hypothesised) evolutionary importance of these interactions declined, which reduced selection for extended post-reproductive lifespan.
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Affiliation(s)
| | - Virpi Lummaa
- Department of Biology, University of Turku, Finland
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2
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Kauppi JJ, Chapman SN, Pettay JE, Lahdenperä M, Lummaa V, Loehr J. Sex, age, and family structure influence dispersal behaviour after a forced migration. Evol Hum Sci 2023; 5:e21. [PMID: 37587948 PMCID: PMC10426002 DOI: 10.1017/ehs.2023.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/18/2023] Open
Abstract
Dispersal does not only mean moving from one environment to another, but can also refer to shifting from one social group to another. Individual characteristics such as sex, age and family structure might influence an individual's propensity to disperse. In this study, we use a unique dataset of an evacuated World War II Finnish population, to test how sex, age, number of siblings and birth order influence an individual's dispersal away from their own social group at a time when society was rapidly changing. We found that young women dispersed more than young men, but the difference decreased with age. This suggests that young men might benefit more from staying near a familiar social group, whereas young women could benefit more from moving elsewhere to find work or spouses. We also found that having more younger brothers increased the propensity for firstborns to disperse more than for laterborns, indicating that younger brothers might pressure firstborn individuals into leaving. However, sisters did not have the same effect as brothers. Overall, the results show that individual characteristics are important in understanding dispersal behaviour, but environmental properties such as social structure and the period of flux after World War II might upend the standard predictions concerning residence and dispersal. Social media summary: Individual characteristics influence dispersal away from social group after a forced migration in a Finnish population.
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Affiliation(s)
- Jenni J. Kauppi
- Department of Biology, University of Turku, 20014Turku, Finland
| | - Simon N. Chapman
- INVEST Flagship Research Centre, University of Turku, 20014Turku, Finland
| | - Jenni E. Pettay
- INVEST Flagship Research Centre, University of Turku, 20014Turku, Finland
| | | | - Virpi Lummaa
- Department of Biology, University of Turku, 20014Turku, Finland
| | - John Loehr
- University of Helsinki, 00014Helsinki, Finland
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3
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Ukonaho S, Chapman SN, Briga M, Lummaa V. Grandmother presence improved grandchild survival against childhood infections but not vaccination coverage in historical Finns. Proc Biol Sci 2023; 290:20230690. [PMID: 37253424 PMCID: PMC10229226 DOI: 10.1098/rspb.2023.0690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 05/02/2023] [Indexed: 06/01/2023] Open
Abstract
Grandmother presence can improve the number and survival of their grandchildren, but what grandmothers protect against and how they achieve it remains poorly known. Before modern medical care, infections were leading causes of childhood mortality, alleviated from the nineteenth century onwards by vaccinations, among other things. Here, we combine two individual-based datasets on the genealogy, cause-specific mortality and vaccination status of eighteenth- and nineteenth-century Finns to investigate two questions. First, we tested whether there were cause-specific benefits of grandmother presence on grandchild survival from highly lethal infections (smallpox, measles, pulmonary and diarrhoeal infections) and/or accidents. We show that grandmothers decreased all-cause mortality, an effect which was mediated through smallpox, pulmonary and diarrhoeal infections, but not via measles or accidents. Second, since grandmothers have been suggested to increase vaccination coverage, we tested whether the grandmother effect on smallpox survival was mediated through increased or earlier vaccination, but we found no evidence for such effects. Our findings that the beneficial effects of grandmothers are in part driven by increased survival from some (but not all) childhood infections, and are not mediated via vaccination, have implications for public health, societal development and human life-history evolution.
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Affiliation(s)
- Susanna Ukonaho
- Department of Biology, University of Turku, 20014 Turku, Finland
| | - Simon N. Chapman
- INVEST Flagship Research Centre, University of Turku, 20014 Turku, Finland
| | - Michael Briga
- Department of Biology, University of Turku, 20014 Turku, Finland
- Infectious Disease Epidemiology Group, Max Planck Institute for Infection Biology, 10117 Berlin, Germany
| | - Virpi Lummaa
- Department of Biology, University of Turku, 20014 Turku, Finland
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4
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Mumby HS, Chapman SN, Crawley JAH, Mar KU, Htut W, Soe AT, Aung HH, Lummaa V. Correction to: Distinguishing between determinate and indeterminate growth in a long-lived mammal. BMC Ecol Evol 2021; 21:217. [PMID: 34872496 PMCID: PMC8647441 DOI: 10.1186/s12862-021-01951-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Hannah S Mumby
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK.
| | - Simon N Chapman
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK
| | - Jennie A H Crawley
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK
| | - Khyne U Mar
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK
| | - Win Htut
- Ministry of Environmental Conservation and Forestry, Myanmar Timber Enterprise, Yangon, Myanmar
| | - Aung Thura Soe
- Ministry of Environmental Conservation and Forestry, Myanmar Timber Enterprise, Yangon, Myanmar
| | - Htoo Htoo Aung
- Ministry of Environmental Conservation and Forestry, Myanmar Timber Enterprise, Yangon, Myanmar
| | - Virpi Lummaa
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK
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Lynch R, Lummaa V, Briga M, Chapman SN, Loehr J. Child volunteers in a women's paramilitary organization in World War II have accelerated reproductive schedules. Nat Commun 2020; 11:2377. [PMID: 32398652 PMCID: PMC7217904 DOI: 10.1038/s41467-020-15703-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Accepted: 02/27/2020] [Indexed: 11/09/2022] Open
Abstract
Understanding how conditions experienced during development affect reproductive timing is of considerable cross-disciplinary interest. Life-history theory predicts that organisms will accelerate reproduction when future survival is unsure. In humans, this can be triggered by early exposure to mortality. Previous studies, however, have been inconclusive due to several confounds that are also likely to affect reproduction. Here we take advantage of a natural experiment in which a population is temporarily divided by war to analyze how exposure to mortality affects reproduction. Using records of Finnish women in World War II, we find that young girls serving in a paramilitary organization wait less time to reproduce, have shorter inter-birth intervals, and have more children than their non-serving peers or sisters. These results support the hypothesis that exposure to elevated mortality rates during development can result in accelerated reproductive schedules and adds to our understanding of how participation in warfare affects women. Life history theory predicts that females will adjust reproductive timing in response to environmental challenges. Here the authors show that young girls exposed to higher mortality rates during war give birth earlier and more often than their peers who were not exposed to these conditions.
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Affiliation(s)
| | | | | | | | - John Loehr
- University of Helsinki, Helsinki, Finland
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6
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Reichert S, Berger V, Jackson J, Chapman SN, Htut W, Mar KU, Lummaa V. Maternal age at birth shapes offspring life-history trajectory across generations in long-lived Asian elephants. J Anim Ecol 2020; 89:996-1007. [PMID: 31222736 DOI: 10.1111/1365-2656.13049] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 04/14/2019] [Indexed: 11/30/2022]
Abstract
Advanced maternal age at birth can have pronounced consequences for offspring health, survival and reproduction. If carried over to the next generation, such fitness effects could have important implications for population dynamics and the evolution of ageing, but these remain poorly understood. While many laboratory studies have investigated maternal age effects, relatively few studies have been conducted in natural populations, and they usually only present a "snapshot" of an offspring's lifetime. In the present study, we focus on how maternal age influences offspring life-history trajectories and performance in a long-lived mammal. We use a multigenerational demographic dataset of semi-captive Asian elephants to investigate maternal age effects on several offspring life-history traits: condition, reproductive success and overall survival. We show that offspring born to older mothers display reduced overall survival but higher reproductive success, and reduced survival of their own progeny. Our results show evidence of a persistent effect of maternal age on fitness across generations in a long-lived mammal. By highlighting transgenerational effects on the fitness of the next generation associated with maternal age, the present study helps increase our understanding of factors contributing to individual variation in ageing rates and fitness.
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Affiliation(s)
- Sophie Reichert
- Department of Biology, University of Turku, Turku, Finland
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| | - Vérane Berger
- Department of Biology, University of Turku, Turku, Finland
| | - John Jackson
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK
| | | | - Win Htut
- Ministry of Natural Resources and Environmental Conservation, Myanma Timber Enterprise, Yangon, Myanmar
| | - Khyne U Mar
- Department of Biology, University of Turku, Turku, Finland
| | - Virpi Lummaa
- Department of Biology, University of Turku, Turku, Finland
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Pettay JE, Chapman SN, Lahdenperä M, Lummaa V. Family dynamics and age-related patterns in marriage probability. EVOL HUM BEHAV 2020. [DOI: 10.1016/j.evolhumbehav.2019.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Abstract
BACKGROUND The existence of extended post-reproductive lifespan is an evolutionary puzzle, and its taxonomic prevalence is debated. One way of measuring post-reproductive life is with post-reproductive representation, the proportion of adult years lived by females after cessation of reproduction. Analyses of post-reproductive representation in mammals have claimed that only humans and some toothed whale species exhibit extended post-reproductive life, but there are suggestions of a post-reproductive stage for false killer whales and Asian elephants. Here, we investigate the presence of post-reproductive lifespan in Asian elephants using an extended demographic dataset collected from semi-captive timber elephants in Myanmar. Furthermore, we investigate the sensitivity of post-reproductive representation values to availability of long-term data over 50 years. RESULTS We find support for the presence of an extended post-reproductive stage in Asian elephants, and that post-reproductive representation and its underlying demographic rates depend on the length of study period in a long-lived animal. CONCLUSIONS The extended post-reproductive lifespan is unlikely due to physiological reproductive cessation, and may instead be driven by mating preferences or condition-dependent fertility. Our results also show that it is crucial to revisit such population measures in long-lived species as more data is collected, and if the typical lifespan of the species exceeds the initial study period.
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Affiliation(s)
| | - John Jackson
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK
| | - Win Htut
- Myanma Timber Enterprise, Ministry of Natural Resources and Environment Conservation, Yangon, Myanmar
| | - Virpi Lummaa
- Department of Biology, University of Turku, Turku, Finland
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Chapman SN, Pettay JE, Lummaa V, Lahdenperä M. Limits to Fitness Benefits of Prolonged Post-reproductive Lifespan in Women. Curr Biol 2019; 29:645-650.e3. [PMID: 30744967 DOI: 10.1016/j.cub.2018.12.052] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 11/17/2018] [Accepted: 12/19/2018] [Indexed: 11/16/2022]
Abstract
Recent advances in medicine and life-expectancy gains have fueled multidisciplinary research into the limits of human lifespan [1-3]. Ultimately, how long humans can live for may depend on selection favoring extended longevity in our evolutionary past [4]. Human females have an unusually extended post-reproductive lifespan, which has been explained by the fitness benefits provided from helping to raise grandchildren following menopause [5, 6]. However, formal tests of whether such grandmothering benefits wane with grandmother age and explain the observed length of post-reproductive lifespan are missing. This is critical for understanding prevailing selection pressures on longevity but to date has been overlooked as a possible mechanism driving the evolution of lifespan. Here, we use extensive data from pre-industrial humans to show that fitness gains from grandmothering are dependent on grandmother age, affecting selection on the length of post-reproductive lifespan. We find both opportunities and ability to help grandchildren declined with age, while the hazard of death of women increased greatly in their late 60s and 70s compared to menopausal ages, together implying waning selection on subsequent longevity. The presence of maternal grandmothers aged 50-75 increased grandchild survival after weaning, confirming the fitness advantage of post-reproductive lifespan. However, co-residence with paternal grandmothers aged 75+ was detrimental to grandchild survival, with those grandmothers close to death and presumably in poorer health particularly associated with lower grandchild survival. The age limitations of gaining inclusive fitness from grandmothering suggests that grandmothering can select for post-reproductive longevity only up to a certain point.
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Affiliation(s)
- Simon N Chapman
- Department of Biology, University of Turku, 20014 Turku, Finland
| | - Jenni E Pettay
- Department of Biology, University of Turku, 20014 Turku, Finland
| | - Virpi Lummaa
- Department of Biology, University of Turku, 20014 Turku, Finland.
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10
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Abstract
Grandmothers provide key care to their grandchildren in both contemporary and historic human populations. The length of the grandmother-grandchild relationship provides a basis for such interactions, but its variation and determinants have rarely been studied in different contexts, despite changes in age-specific mortality and fertility rates likely having affected grandmotherhood patterns across the demographic transition. Understanding how often and long grandmothers have been available for their grandchildren in different conditions may help explain the large differences between grandmaternal effects found in different societies, and is vital for developing theories concerning the evolution of menopause, post-reproductive longevity, and family living. Using an extensive genealogical dataset from Finland spanning the demographic transition, we quantify the length of grandmotherhood and its determinants from 1790–1959. We found that shared time between grandmothers and grandchildren was consistently low before the demographic transition, only increasing greatly during the 20th century. Whilst reduced childhood mortality and increasing adult longevity had a role in this change, grandmaternal age at birth remained consistent across the study period. Our findings further understanding of the temporal context of grandmother-grandchild relationships, and emphasise the need to consider the demography of grandmotherhood in a number of disciplines, including biology (e.g. evolution of the family), sociology (e.g. changing family structures), population health (e.g. changing age structures), and economics (e.g. workforce retention).
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Affiliation(s)
- Simon N. Chapman
- Department of Biology, University of Turku, Turku, Finland
- * E-mail:
| | | | | | - Virpi Lummaa
- Department of Biology, University of Turku, Turku, Finland
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11
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Chapman SN, Pettay JE, Lummaa V, Lahdenperä M. Limited support for the X-linked grandmother hypothesis in pre-industrial Finland. Biol Lett 2018; 14:rsbl.2017.0651. [PMID: 29321245 DOI: 10.1098/rsbl.2017.0651] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 12/11/2017] [Indexed: 01/28/2023] Open
Abstract
The level of kin help often depends on the degree of relatedness between a helper and the helped. In humans, grandmother help is known to increase the survival of grandchildren, though this benefit can differ between maternal grandmothers (MGMs) and paternal grandmothers (PGMs) and between grandsons and granddaughters. The X-linked grandmother hypothesis posits that differential X-chromosome relatedness between grandmothers and their grandchildren is a leading driver of differential grandchild survival between grandmother lineages and grandchild sexes. We tested this hypothesis using time-event models on a large, multigenerational dataset from pre-industrial Finland. We found that the presence of an MGM increases grandson survival more than PGM presence, and that granddaughter survival is higher than that of grandsons in the presence of a PGM. However, there was no support for the key prediction that the presence of PGMs improves granddaughter survival more than that of MGMs, diminishing the overall support for the hypothesis. Our results call for alternative explanations for differences in the effects of maternal and paternal kin to grandchild survival in humans.
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Affiliation(s)
- Simon N Chapman
- Department of Biology, University of Turku, Turku 20014, Finland
| | - Jenni E Pettay
- Department of Biology, University of Turku, Turku 20014, Finland
| | - Virpi Lummaa
- Department of Biology, University of Turku, Turku 20014, Finland
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Crawley JA, Chapman SN, Lummaa V, Lynsdale CL. Testing storage methods of faecal samples for subsequent measurement of helminth egg numbers in the domestic horse. Vet Parasitol 2016; 221:130-3. [DOI: 10.1016/j.vetpar.2016.03.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 03/11/2016] [Accepted: 03/15/2016] [Indexed: 01/19/2023]
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Chapman SN, Mumby HS, Crawley JAH, Mar KU, Htut W, Thura Soe A, Aung HH, Lummaa V. How Big Is It Really? Assessing the Efficacy of Indirect Estimates of Body Size in Asian Elephants. PLoS One 2016; 11:e0150533. [PMID: 26938085 PMCID: PMC4777392 DOI: 10.1371/journal.pone.0150533] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 02/15/2016] [Indexed: 12/03/2022] Open
Abstract
Information on an organism’s body size is pivotal in understanding its life history and fitness, as well as helping inform conservation measures. However, for many species, particularly large-bodied wild animals, taking accurate body size measurements can be a challenge. Various means to estimate body size have been employed, from more direct methods such as using photogrammetry to obtain height or length measurements, to indirect prediction of weight using other body morphometrics or even the size of dung boli. It is often unclear how accurate these measures are because they cannot be compared to objective measures. Here, we investigate how well existing estimation equations predict the actual body weight of Asian elephants Elephas maximus, using body measurements (height, chest girth, length, foot circumference and neck circumference) taken directly from a large population of semi-captive animals in Myanmar (n = 404). We then define new and better fitting formulas to predict body weight in Myanmar elephants from these readily available measures. We also investigate whether the important parameters height and chest girth can be estimated from photographs (n = 151). Our results show considerable variation in the ability of existing estimation equations to predict weight, and that the equations proposed in this paper predict weight better in almost all circumstances. We also find that measurements from standardised photographs reflect body height and chest girth after applying minor adjustments. Our results have implications for size estimation of large wild animals in the field, as well as for management in captive settings.
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Affiliation(s)
- Simon N. Chapman
- Department of Animal and Plant Science, University of Sheffield, Western Bank, Sheffield, S10 2TN, United Kingdom
| | - Hannah S. Mumby
- Department of Animal and Plant Science, University of Sheffield, Western Bank, Sheffield, S10 2TN, United Kingdom
- Department of Zoology, University of Cambridge, Downing Street, Cambridge, CB2 3EJ, United Kingdom
- * E-mail:
| | - Jennie A. H. Crawley
- Department of Animal and Plant Science, University of Sheffield, Western Bank, Sheffield, S10 2TN, United Kingdom
| | - Khyne U. Mar
- Department of Animal and Plant Science, University of Sheffield, Western Bank, Sheffield, S10 2TN, United Kingdom
| | - Win Htut
- Myanma Timber Enterprise, Extraction Department, Ministry for Environmental Conservation and Forestry, Yangon, Myanmar
| | - Aung Thura Soe
- Myanma Timber Enterprise, Extraction Department, Ministry for Environmental Conservation and Forestry, Yangon, Myanmar
| | - Htoo Htoo Aung
- Myanma Timber Enterprise, Extraction Department, Ministry for Environmental Conservation and Forestry, Yangon, Myanmar
| | - Virpi Lummaa
- Department of Biology, University of Turku, FIN-20014, Turku, Finland
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14
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Mumby HS, Chapman SN, Crawley JAH, Mar KU, Htut W, Thura Soe A, Aung HH, Lummaa V. Distinguishing between determinate and indeterminate growth in a long-lived mammal. BMC Evol Biol 2015; 15:214. [PMID: 26464339 PMCID: PMC4604763 DOI: 10.1186/s12862-015-0487-x] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 09/14/2015] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND The growth strategy of a species influences many key aspects of its life-history. Animals can either grow indeterminately (throughout life), or grow determinately, ceasing at maturity. In mammals, continued weight gain after maturity is clearly distinguishable from continued skeletal growth (indeterminate growth). Elephants represent an interesting candidate for studying growth because of their large size, long life and sexual dimorphism. Objective measures of their weight, height and age, however, are rare. RESULTS We investigate evidence for indeterminate growth in the Asian elephant Elephas maximus using a longitudinal dataset from a semi-captive population. We fit growth curves to weight and height measurements, assess sex differences in growth, and test for indeterminate growth by comparing the asymptotes for height and weight curves. Our results show no evidence for indeterminate growth in the Asian elephant; neither sex increases in height throughout life, with the majority of height growth completed by the age of 15 years in females and 21 years in males. Females show a similar pattern with weight, whereas males continue to gain weight until over age 50. Neither sex shows any declines in weight with age. CONCLUSIONS These results have implications for understanding mammalian life-history, which could include sex-specific differences in trade-offs between size and reproductive investment.
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Affiliation(s)
- Hannah S Mumby
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK.
| | - Simon N Chapman
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK.
| | - Jennie A H Crawley
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK.
| | - Khyne U Mar
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK.
| | - Win Htut
- Ministry of Environmental Conservation and Forestry, Myanma Timber Enterprise, Yangon, Myanmar.
| | - Aung Thura Soe
- Ministry of Environmental Conservation and Forestry, Myanma Timber Enterprise, Yangon, Myanmar.
| | - Htoo Htoo Aung
- Ministry of Environmental Conservation and Forestry, Myanma Timber Enterprise, Yangon, Myanmar.
| | - Virpi Lummaa
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK.
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15
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Tilsner J, Cowan GH, Roberts AG, Chapman SN, Ziegler A, Savenkov E, Torrance L. Plasmodesmal targeting and intercellular movement of potato mop-top pomovirus is mediated by a membrane anchored tyrosine-based motif on the lumenal side of the endoplasmic reticulum and the C-terminal transmembrane domain in the TGB3 movement protein. Virology 2010; 402:41-51. [PMID: 20350737 DOI: 10.1016/j.virol.2010.03.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2009] [Revised: 12/02/2009] [Accepted: 03/03/2010] [Indexed: 12/27/2022]
Abstract
Live-cell fluorescence microscopy was used to investigate the third triple gene block protein (TGB3) of potato mop-top pomovirus and its role in assisted targeting of TGB2 to plasmodesmata (PD). Wild-type and mutant TGB3 proteins were expressed under the control of the 35S promoter or from a virus reporter clone. Assisted targeting of TGB2 to PD was optimal when the proteins were expressed from a bicistronic plasmid in the relative ratios expected in a virus infection, suggesting that excess TGB3 inhibited PD localisation. Contrary to the generally accepted view, bimolecular fluorescence complementation showed that the TGB3 N terminus is located in the cytosol. Mutational analysis to dissect TGB3 sub domain functions showed that PD targeting was mediated by a composite signal comprising an ER-lumenal tyrosine-based motif and the C-terminal transmembrane domain. Mutation of either of these domains also abolished cell-to-cell movement of the virus. The results are discussed in the context of TGB3 membrane topology.
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Affiliation(s)
- J Tilsner
- Plant Pathology Programme, Scottish Crop Research Institute, Invergowrie, DD2 5DA, UK
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16
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Grdzelishvili VZ, Chapman SN, Dawson WO, Lewandowski DJ. Mapping of the Tobacco mosaic virus movement protein and coat protein subgenomic RNA promoters in vivo. Virology 2000; 275:177-92. [PMID: 11017798 DOI: 10.1006/viro.2000.0511] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The Tobacco mosaic virus movement protein (MP) and coat protein (CP) are expressed from 3'-coterminal subgenomic RNAs (sgRNAs). The transcription start site of the MP sgRNA, previously mapped to positions 4838 (Y. Watanabe, T. Meshi, and Y. Okada (1984), FEBS Lett. 173, 247-250) and 4828 (K. Lehto, G. L. Grantham, and W. O. Dawson (1990), Virology 174, 145-157) for the TMV OM and U1 strains, respectively, has been reexamined and mapped to position 4838 for strain U1. Sequences of the MP and CP sgRNA promoters were delineated by deletion analysis. The boundaries for minimal and full MP sgRNA promoter activity were localized between -35 and +10 and -95 and +40, respectively, relative to the transcription start site. The minimal CP sgRNA promoter was mapped between -69 and +12, whereas the boundaries of the fully active promoter were between -157 and +54. Computer analysis predicted two stem-loop structures (SL1 and SL2) upstream of the MP sgRNA transcription start site. Deletion analysis and site-directed mutagenesis suggested that SL1 secondary structure, but not its sequence, was required for MP sgRNA promoter activity, whereas a 39-nt deletion removing most of the SL2 region increased MP sgRNA accumulation fourfold. Computer-predicted folding of the fully active CP sgRNA promoter revealed one long stem-loop structure. Deletion analysis suggested that the upper part of this stem-loop, located upstream of the transcription start site, was essential for transcription and that the lower part of the stem had an enhancing role.
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MESH Headings
- Base Sequence
- Capsid/genetics
- Gene Expression Regulation, Viral
- Genome, Viral
- Molecular Sequence Data
- Mutation/genetics
- Nucleic Acid Conformation
- Open Reading Frames/genetics
- Physical Chromosome Mapping
- Plant Viral Movement Proteins
- Plants, Toxic
- Promoter Regions, Genetic/genetics
- RNA, Spliced Leader/chemistry
- RNA, Spliced Leader/genetics
- RNA, Viral/analysis
- RNA, Viral/biosynthesis
- RNA, Viral/chemistry
- RNA, Viral/genetics
- Sequence Alignment
- Nicotiana/cytology
- Nicotiana/virology
- Tobacco Mosaic Virus/genetics
- Transcription, Genetic/genetics
- Viral Proteins/genetics
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Affiliation(s)
- V Z Grdzelishvili
- Department of Plant Pathology, CREC, University of Florida, Lake Alfred, Florida 33850, USA
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Chapman SN. Adapting just-in-time inventory control to the hospital setting. Hosp Mater Manage 1986; 11:8-12. [PMID: 10279787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
The principles of Just-in-Time inventory management are essentially those of sensible management of productivity and waste. Much of the literature written about JIT, however, is limited in scope in that it focuses on applications in a manufacturing operation. The best way to assess JIT's applicability to all businesses, including hospitals, is to synthesize the characteristics into a basic, conceptual model, which the author does in the following article.
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